1946 CJ-2A Slightly Above Stock

I suppose I will start here. Some pictures from the day I picked him up are over on the introduction but I figured I would start this thread here as I begin to tear down and rebuild.


So I got the front hubs, drums, and backings off this morning. It really seems like the axle and bearings are in great shape. It has some Selectro manual locking hubs that were installed and after some research I believe that was a good upgrade. I knew going in that there was going to need some brake work done so that was the reason to start with the front axles. I am going to convert to disc up there and it appears that Brennan's setup may be the best fit. I have already ordered most of the parts and am waiting for those and a good day for the install. I was pleasantly surprised to find that the lines seem to be intact without leaks. However, there was very little pressure even though there was some movement on the shoes when the pedal was pressed to the floorboard. I have read and heard that using the original single reservoir master cylinder is probably not the best idea with discs especially. Does anyone have any input on whether they have had experience with that? I would really like to test out the conversion with the single before I upgrade to dual and start changing too many more things.

OK JoeyD, now lets see those pictures!

5JeepsAz has a lot of experience with converting to Disc's. I would check out his upgrade on his truck. Also TJones has a radically tricked out CJ that is something to see.


https://willysjeepforum.kaiserwillys...w-to-the-Forum

bmorgil, you weren't kidding about that CJ of TJones. He really did some custom stuff there and I like the way he has that roll cage on the inside. Guess I will just have to work my own magic as he seems to have done. 5JeepsAz really did a nice job on his rig too, but I didn't see exactly where he mentioned if he actually attempted to do the disc conversion with the single cylinder first. Thanks for the quick information grab.

Hey Joey, yes, it's a good idea to skip off the single cylinder. Won't do fluid push required, even if specs say it will. Master cylinder went in after the discs being in the same spot then you are now. Lost sleep worrying about having these beauty brakes installed and a hole in my bay where the master cylinder should be, in case new ones didn't fit. Turned out fine, good fitment on the fire wall due to good selecting and good wrenching by the guys doing my build. I even looked at some master cylinder with a pedal hanging off and how to insert that through the firewall. Freaking nightmare.

Forum gurus told me about brakes. I didn't listen and with that original singleness in place and freshly serviced original brakes I pounced on the brake pedal and ended up in the other lane before I could say 4wheel disc conversion and a 78 corvette master cylinder. I believed some hack who told me it worked good back then, so, as long as it's serviced, it'll work good now. Not in modern traffic. For me anyway!

We are unified in one thing above all else, and I am glad I finally listened even if I didn't at first: do good brake work.

My build, goal, something serviceable by any modern mechanic, parts available convenient, since it's a daily.That meant upgrade all around. Had a hell of a time locating parts so went modernized.

Had that brake situation been in traffic or near pedestrians, tragedy would have been on me. So I took responsibility not for me, but to protect those around me. Not preaching. Hell I run over fences and near miss fire hydrants on u turns cause I refuse power steering. And I don't have an ebrake.

Sorry long post. Anyways, the word from up high around here is good brakes are essential. Looking forward to your build!

Joey, 5JeepsAz is modest, he has more he's not telling you. His system is a nice one. It utilizes a Corvette Dual reservoir master cylinder and 4 wheel disc brakes. In addition he is using a vacuum power booster and a vacuum reservoir to make it act like a modern braking system.

He (Az), has a tendency to run over fences, so good brakes are very important on his vehicles. He also is predisposed to drive in populated areas using driving techniques that require 3 feet and 3 hands, while enjoying the air conditioning. It takes some planning to get Air, and Power Brakes to play nicely together on an old classic motor. There is another member on here who has begun a CJ conversion. I cant find it but, he was going to start with just the rears. That has control issues, so I believe he was aware he needs to do the front first to avoid a dangerous situation. That said I am quite sure a CJ with front discs and stock rear drums will stop on a dime.

Az, that makes a ton of since and I have been trying to read as much about this conversion as possible. Sometimes I feel like I am at the end of that firehose trying to drink. Mechanically I feel pretty sound and at this point I am trying to do just about everything myself with a some help from my lady (she ain't bad, it's a bonus). I just want to make sure as you said, "do good brake work". As bmorgil mentioned these 2As weigh nothing and with front disc, rear drum I believe it is going to stop just fine. Just like Dad always said, I just want to do it right the first time. With that being said, it sounds as though you went a little more modern than I have been planning for in the cylinder department. Herm has the Dual Cylinder that mounts in the same location on the frame as the original single is right now. So I suppose it just means, place that order and get it here. Thanks for clearing up the "will it have the pressure it needs" question, really a big help with making the decision.

On an update note, I am having some trouble getting the axle nut off the rear. I want to at least check those rear drums and shoes out before I start running fluid through there and testing after the front conversion. The nut doesn't look that bad it is just seriously on there, both sides. Any tricks for me to get that dang thing off of there? I hate to think I need to resort to anything out of the ordinary. As always thanks for all of the conversion, I really can't stop messing with this CJ now that I have started...lol

JoeyD, It is on there as tight as you can imagine. Most who are familiar with the tapered axle are used to them coming loose enough to make noise. The nut should be torqued to 150 to 175 ft lbs of torque. To get it off use the biggest stuff you have and a long leverage bar like a pipe or, a real good impact gun with a lot of air or a big battery. Make sure the cotter key is out.

Another issue was changing wheels to fit around the discs. Not sure if that's an issue on the CJ but it was on the SJ truck. I did want to do it like you are planning. That's always the best. Start with keeping it original, try mod close to original, fully modern only when needed. Mine had every challenge for the brakes, so the rabbit hole led past Herm and Walcks, though they were super helpful and I met great jeep people, legends really if you think what a few knowledge keepers are doing for guys like us, along the way. It came down to "what's on your Jeep is on your Jeep". I had different drum size than parts available, one truck model later than plumbing available, too early for changing in parts off of the regular j truck set ups although they would have worked if fully transferred it was same thing to just go modern (mine is early in j truck series). These guys on here who had been through kept telling me the build, the journey, is all the fun. Looking back it is all true. But I surely appreciate where you are at with your build. The firehouse as you call it. Keep posting, man. Pictures!!!

So at this point I am just tinkering until I get some parts in. Waiting on the calipers, rotors and lines to finish up the front brakes. Now that I understand from Az I guess I need to go ahead and order that dual cylinder. I also need to get that elbow grease in there and get that castle nut off so I can inspect the rear brakes. I think I am gonna see if any body needs the fronts drums cause they seem to be in decent shape. I did remove the square taillights someone put on there and replaced them with round ones. Really just an aesthetic thing but I like it better. I need to check the brake light switch, but the parking and taillight works just fine. I am curious as to how far with an engine review I need to go. I mean he runs really smooth but it is obvious some PM needs to happen. Here are a few pics I snapped today.Attachment 7557Attachment 7558Attachment 7559Attachment 7560Attachment 7561

Start with a good inspection of the engine. But, if it isn't leaking, leave it alone. You might want to look into adjusting the valves. Read about it, and watch all the videos that you can find so you know everything you will ever need to know about tappets.

You have your priorities right - good brakes! !!

As they say in that phone commercial; "If the brakes don't stop it, something else will"

And old lifters will clatter a bit.

So update, even with this crazy Texas cold snap I managed to get out there and do a few things. On that note, he does not like the cold at all. But after some serious sweet talk and a little ether he fired and ran good. I did the first oil change and let me tell you I have never seen oil that black unless it came straight from the ground. But got it done and the plug looks to still hold a good seal with no leaks anywhere else either. I put 5 quarts of ND 30 and it seems to like that with hardly any burn coming out. I can also tell you that I have no idea how he even got for to start with the plugs that I pulled out of there. They were some kind of rusted on top and black as can be on the ends. But I got the new ones in and he starts great. Here are a couple of pics from those 2 jobs. Back to the front brakes as soon as I get the rest of the parts.Attachment 7618Attachment 7618Attachment 7617Attachment 7619

I do believe you got every bit of good out of both the oil and plugs. He will sure like the new plugs and transfusion.

WOW! Texas crude. When you look at those plugs it is a great sign the ignition is strong. It had to be to fire those iron oxides!

Alright folks, I am kinda freaking out a little.So I told y’all about the trouble starting in the cold but eventually he came back to life. Ran great as always for a little while and then shut him down for the night. Not sure if anyone has been tracking the weather in Texas but it has been crazy for the area to say the least. Went back out this morning because I want to run him as often as possible to keep him from sitting while I work on the things to get him on the road. And what I heard has me really worried and almost lost. Almost a complete lack of wanting to turn over. Before there was no issue turning over just would not fire. Today it was almost like it was frozen from the word go. I didn’t want to try too hard cause I was afraid to do more harm than good. What in the world could have caused the sudden change. It has been converted to 12v, alternator, newer starter and the battery has some years on it but has been holding a charge. Please help me calm down or face what I may have to.

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Originally Posted by JoeyD

Alright folks, I am kinda freaking out a little.So I told y’all about the trouble starting in the cold but eventually he came back to life. Ran great as always for a little while and then shut him down for the night. Not sure if anyone has been tracking the weather in Texas but it has been crazy for the area to say the least. Went back out this morning because I want to run him as often as possible to keep him from sitting while I work on the things to get him on the road. And what I heard has me really worried and almost lost. Almost a complete lack of wanting to turn over. Before there was no issue turning over just would not fire. Today it was almost like it was frozen from the word go. I didn’t want to try too hard cause I was afraid to do more harm than good. What in the world could have caused the sudden change. It has been converted to 12v, alternator, newer starter and the battery has some years on it but has been holding a charge. Please help me calm down or face what I may have to.

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You might try putting an electric heater under it and warm up the block and see what happens. When I was in high school I inherited an old mustang from an uncle and it would do this in the winter time.

Deep breath, check out the easy stuff first Gotta check the condition of the battery. If you have no means to do it yourself (voltmeter), Take the battery to your local auto parts store and tell them to check it out. If the battery is good, rent or buy a 1 3/8" socket and a way to turn it. This socket should fit the crankshaft nut. If you have or have access to the hand crank, this will also do the trick https://www.kaiserwillys.com/starter...s-41-45-mb-gpw .

See if you can get the motor to turn over by hand. If it was running fine when you shut it off I am sure it will be running fine again.

Here may be an idea. The oil you drained was really nasty stuff, but we don’t know its’ viscosity. It could have been 10W30 or even 5W30. You refilled it with 30W non-detergent oil, a good choice normally - but in the current Texas cold, straight 30W is going to be hard to move around.

Check the battery. I agree with the heater suggestion - maybe even a blanket to hold warm air under the Jeep. Don’t panic yet, just make sure there is anti-freeze in it!

Thanks guys I really appreciate the suggestions and reassuring words. Trailabite I have been looking for a heater but of course those were the first things to go around here after the eggs and milk. Still looking and maybe I'll try the blanket in the meantime.

Bmorgil, I have had a charger on the battery most of the time but I didn't consider that at this point I may have gotten the last out of it. I knew you could hand crank but as strong as the starter and battery had been I hadn't thought that could be a way to rule some things out. I will see what I need to get to try that out. I really want this weather to break to see if that makes all the difference.

Larrbeard that has been running through my mind the whole time. Even growing up in Arkansas where it can get this cold I never saw this happen. But then again I never used straight 30W. I have already been religiously checking the fluid in the radiator and it has stayed consistent.

Would yall think I might just be better to let these temps rise before i try again and go from there? It is just real hard with all this free time and looking out the window at it just waiting to be driven. But I am going to keep tinkering with other things until this crap clears up. Hopefully before it ever happens again I can get moved to warmer weather. Thanks again and I will keep y'all updated.

I agree with the battery. Batteries will crap out overnight, when the weather changes drastically. In a usual warm climate like Texas, the battery doesn't see big swings in temperature over its life span. When you hit down in to the single digits, the battery can't take it. I've never had battery issues until moving to a warmer climate. In the far north, I could park a vehicle in the fall, and it would sit all winter without being on a charger. It the spring, fill up the float bowls with fuel and the garbage would fire right up. The temps in the winter would get down to -20 to -30 during the storage period, but it wouldn't effect the battery performance or the life span. Battery brands do not seem to make a difference around here either. I have run Interstates and Exides for years, and both do not last as long here in comparison.

I would also check the antifreeze to ensure that the freezing point isn't too high.

Joey, I am only suggesting the socket or crank to see if the motor is rotating freely. DO NOT try to start the motor with a socket wrench on the crank nut. Very bad things will happen if it starts! I am suggesting with the key OFF, try to rotate the engine just to make sure the motor didn't strangely freeze up as you mentioned. I have a feeling you have a voltage problem, the battery is highly suspect. If that's not it, and you can turn the motor freely by hand, some basic voltage/amperage checks should get you to the culprit.

GM, I understand what you mean and the swing has been crazy. I have had a battery in my daily driver crap out in less than 6 months here for no apparent reason.

Bm I am sure that would be very bad. And it does seem that the motor turns freely just seems like it is trying too hard when you turn the key. As far a voltage issue I am putting a pic on here because I have noticed something peculiar and worrisome. The negative ground is attached to the alternator bracket mounted to the front of the block. It seems to get real hot and has melted some of the sheathing around the cable. Is this the normal place to put it? Or did someone just wing it?Attachment 7621

The ground is located correct location as with the stock generator would have been. I would grab a multimeter to measure the resistance from the negative battery terminal to the alternator mount where your ground cable terminates. If the resistance is low, check from the negative batt terminal to the braided ground cable at the engine mount. Grease and general crud can reduce the ground flow to the frame. If all is good, check the starter out.

My M38A1 came with Easylok front hubs. They are set in the free position. Do I need to manually set them in the lock position to get any kind of 4 wheel drive? In other words, transferring from 2W to 4W high, should the jeep move or would I hurt anything? I would think I absolutely need to set them to lock position to go from 4W High to 4W Low.

PaulB,

The manual hubs will need to be set to lock for the front wheels to be engaged for four wheel drive to work. The hubs are intended to reduce wear on the front axle by disconnecting the wheel hubs from the axles. This is done to also act as a fuel savings measure by eliminating the parasitic load of having to turn all the internals of the front differential while driving. In short, if the hubs are disconnected from the axles, you are not turning the ring gear and axles.

You can place the transfer case in four wheel drive, and have the hubs in the free position, but it isn't recommended for driving. Also, be sure both hubs are set to the same position. On numerous occasions, I have seen where one hub was locked in, and the other out. On occasion if I am using one of my Heeps for yard maintenance work, where I want the gear reduction of using four wheel low, but do not want to tear up the yard or need to turn on the driveway, I will unlock the hubs to prevent damage. Again, I don't drive on the hard road with the four wheel drive four high/four low engaged because it causes undue stress on the whole four wheel drive system. You can lock the front hubs in though, and drive in two wheel drive with no issues. Then all you would need to do is pull the transfer case levers into the desired mode you wish to use without having to worry about locking and unlocking the hubs. When I lived in a arctic climate, the hubs would be engaged in late October and stayed engaged throughout winter until the following April.

GM, I will check and see what that reading is. I also checked the battery itself yesterday and at full charge, according to the charger, it read almost 13.5 volts. That is way too high, but after a couple of turns on the key it was already back below 12.5. I think I really need to get into that electrical system even though it was something I thought was in pretty decent shape.

PaulB, GM hit it right on the head. I remember my old '86 Yota I had as a teenager hated having the hubs locked and doing more than about 25 mph. I know now it could have just been some bearings needed replaced but I can still hear that whine if I came out of the woods and forgot to unlock them. It is my understanding, correct me if I am wrong guys, but these CJs did not come with manual locking hubs orginally. I know it can be annoying but generally I never locked them in unless I thought I was gonna need it. My 2A has Selectro locking hubs and they seem to be super easy to lock and unlock.

You are correct Joey. The locking hubs were an aftermarket accessory well into the CJ5 production. What turned the corner for Willys and later Kaiser to start putting them on from the factory was through the competition putting them on their units as a selling feature. International Scouts had IH branded Warn locking hubs on their vehicles, then Ford followed suit on the Broncos.

More information than you could probably ever want to know from eWillys.com;

http://www.ewillys.com/?s=locking+hubs

On the electrical side of things, it would appear that you do have some rather high resistance.

GM thanks for the locking hubs explanation & info!

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Originally Posted by JoeyD

GM, I understand what you mean and the swing has been crazy. I have had a battery in my daily driver crap out in less than 6 months here for no apparent reason.

Bm I am sure that would be very bad. And it does seem that the motor turns freely just seems like it is trying too hard when you turn the key. As far a voltage issue I am putting a pic on here because I have noticed something peculiar and worrisome. The negative ground is attached to the alternator bracket mounted to the front of the block. It seems to get real hot and has melted some of the sheathing around the cable. Is this the normal place to put it? Or did someone just wing it?Attachment 7621

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No signs of melting or heat should be anywhere in your electrical system. You have found a source of current loss. It needs to be fixed. I am sure that is a good part of the problem. Red hot wires are the definition of current draw. There is some "Winging" going on but I am not sure for what. The wires taped up and stuck under the clamp nut on the battery terminals are not stock. It looks like you have a few things tapped into the electrical system. I would start by following gm's line of thinking. Start looking for voltage loss. As gm said if all is good pull the starter and have it checked at the auto parts store. Remember a battery can read fully charged (Voltage reading) and have zero amperage capability. This is why they must be checked under load. Just a voltage check at the battery has fooled a lot of people. Maybe LarrBeard can school us on "surface charge" here, if he see's this.

Put a voltmeter on the starter from the positive wire connection to ground. It should be exactly the same as the voltage at the Positive battery post. Crank the motor and see what the voltage drops to. If the voltage drops below 9 or 10 volts at the starter that's too low. Check it at the battery terminals while cranking. If it drops below 9 or 10 volts, the battery has lost its amp-pacity. If it is higher at the Battery while cranking than it is at the starter by more than .2 (point two) volts. You have a wiring issue. If all seems good and the battery is checking OK at the auto parts store, you probably have a bad starter. You really need to use an inductive ammeter to check the starter on the car but, if you have made these checks and the starter is getting hot, it is suspect. Keep after it Joey!

Bm I definitely need to do some checking on the electrical system. There is something going on there and I need to find it before something really gets too hot. You are correct that there are several things tied into there. Winch and KC lights for a start.

On a great note though, as temperature began to rise I decided to see what may happen. I took the battery to the parts store and it checked out good. So I came back and in the middle of the day when the sun was just right I tried again. And what do you know, he finally decided to give me enough to turn it over. I went out and cranked him yesterday too and didn't even need the choke. I will tell y'all this though, I have done so much reading and listening to y'all that I have alot better understanding of how these things are laid out and can be stubborn. I will keep you all updated.

Second note, I cleaned off the drums and shoes from the front that I plan on converting to disc. You would not believe the meat still left on those, you can still see some black lettering on the shoes. Actually considering throwing them back on till my calipers, rotors and lines come in. Really had a big hiccup on those and I am not gonna be able to wait much longer before I get behind the wheel.

Thanks again and I will be doing alot more checking of that electrical system.

All good Joey!

Yet another Hiccup. So I had some issues with a broken bolt on one of my front hubs. The bolt is for the axle flange and I just could not get it out after I broke the head off. So I opted to order new hubs. They were fairly inexpensive and of course new parts equal a little more piece of mind. However, I got them in and started reinstalling the races, bearings and oil seals. Big problem though, the races dropped straight and are now tight. I can literally put them in and take them out with my fingers. The biggest deal is that the oil seals will not seat at all because they are so small. Did I get the wrong hubs, Crown Automotive SKUS437. Now I know I didn't get them from Kaiser's but I thought the price difference was worth it. Can I possibly get new races and oil seal or am I gonna have to return those hubs?

Joey, the parts sound out of dimension. If you are certain you have the right bearing races, they are held to some pretty tight tolerances, that means the hubs are suspect. A lot of crown stuff comes from third world sources. Sometimes you have to make it work. In this case, send it back. The races are a slight press. Too tight will ruin them too loose will ruin them. If you want to get scientific, the installation bore size for the race should be available from the bearing manufacturer. You don't have to pound them in but, they don't fall in either. Are you certain you cant get the broken bolt out? Shoot me a picture of that broken bolt. I might be able to help you there. It is not uncommon to have all but a couple flange bolts broken. I definitely have removed, and seen the removal of many. They are supposed to be grade 8 bolts. Many types end up in there. Cheap bolts break when the poor guy tries to do the right thing and torque them. Or the darn air gun was strong that day!

I agree with Bmorgil. I would remove the broken bolt, and return the out of speck hub. If you run into a problem, drop me a note with your address, and I'll send you an original hub. I've got a few on the shelf, that just need to be cleaned up and new bearings and seals installed.

Just an option to throw out there.

Super options from gm there Joey, both of them. Original hubs if you can.

bmorgil, gmwillys I thought that was probably the right answer and I completely did as you suggested and contacted Morris to send those back. They agreed that I more than likely received the wrong hubs and are sending me a return label. As for the axle flange bolt I will get you that picture and you can tell me with you think.

I will be honest that I really wanted to test the brakes this past weekend so I put everything back together with the one missing bolt. I had already done so much cleaning and my schedule only gives me small windows right now. So I took full advantage because I removed the fill cap on the Master cylinder and found it almost bone dry. I refilled, bled the brakes and found no links in lines. I still have alot of pedal travel so I have been reading the manual to do some adjustments. I am finding some issues that I won't say I am surprised about but was really hoping wouldn't be there. I knew I probably needed to go through the whole thing front to back which isn't an issue, I just didn't want to find anything wrong. I know that was naïve of me, but hey a guy can dream right. As I started to pull out from under the canopy I noticed that I was getting any power to the rear axle. If I engage the front hubs and put it in 4wd my front end has no problem taking me where I want to go. So I did some research and I think that I have ruled out a broken axle rod because the drive shaft turns. Now you may ask if when it is in gear can I turn the rear wheels as well. The answer is yes. I suppose I need to start looking at where drive shaft enters the trans to determine why the rear axle is not engaging. Does that sound about right?

I also checked the battery itself yesterday and at full charge, according to the charger, it read almost 13.5 volts.

That's OK for a battery just off charge. It will settle down a few tenths after it sits for a bit and will pull down to about 12.7 - 12.5 after just a bit of cranking.

If anything is getting hot - it is either a bad connection or badly overloaded. For an example, at stall a 12-volt starter will pull about 350 to 400 amps. It cranks at about 125 to 150 amps. That's a lot of current and even a few milli-ohms (1/1000 of an ohm) will start to generate hot spots.

Clean, bright and tight are the watch words for good electrical connections.

Joey a little confused on your problem. Are you saying in two wheel drive it will not move? In other words if you disengage the transfer case to the front axle (shift it into 2 wheel drive completely disengaging the front drive) the jeep wont move? If it is sitting there in 2 wheel drive not moving with the rear driveshaft spinning, and you are not moving, the rear axle has a problem.

LarrBeard, that is good news to hear about the battery and that is exactly what is happening. Since the thaw the old guy has starting loosening up a bit and is way more easy to get started. In fact, most of the time now there is no need for any choke and only after a couple of days do I need to pump that accelerator a little. Clean is not word I would use for very much on the rig right now, that is partly my fault and partly because that is how I got it. Grandad always told me that things tend to work better when they are clean and I need to get back to that.

bmorgil, That is correct. When I have the middle lever in the "out" position and the right lever in the "high" position it would not move. I did quite a bit of reading last night and went out to do some tinkering when I got home late. After some TLC and a little sweet talking I believe the right lever was sticking in neutral. So I finally got him to move without the front axle engaged. I found that if that right lever is in neutral it stops power transfer to both of the axles. It does take some serious accelerator pressure to start moving in 2wd. I don't notice anything slipping and I want to possibly contribute it to the 34x10.5 Swampers that came on it. These are probably fine for 4wd and off road but could that be a little too much rubber to push with just the rear axle?

I think you have it figured out. The "lever in the middle" would be the transfer case "In" (engaged) and "Out" (disengaged). This controls the power flow through the transfer case. "In" engaged, has power flowing to the front and rear. The lever on the right is the "Range" of the transfer case "Low" and "High", with a neutral in the middle. It can be difficult to get everything to shift. Sometimes it takes a little TLC and slight clutching to get the gears to line up. You probably have tried this technique but just in case, if it seems like it just wont make a positive shift, release the clutch ever so slightly while you try to engage the gear with the shift lever. Be careful here you are trying to line up the gear teeth. You don't want to hear grinding. This is a real "feel" thing. It's like riding a bike however. Once you get used to jumping between the gear positions, it gets a lot easier to feel it. These old transfer cases and transmissions require a bit of touch. It was something you were used to having to do in the 40's, 50's and 60's. The new stuff we have today requires very little driver interaction. A button here or electronic joy stick shifter over there! The directness of the shifter mechanism on the Dana 18 transfer case and the bulk of the components in the gear box is primitive by today's standards. I have to get everything just right on mine every now and then to get her in gear.

How does it do in "Low" range? You need to have the transfer case "In" engaged to shift into "Low" range. Unless someone removed it, there is an interlock in the shift mechanism that prevents the engagement of "Low" unless the Transfer Case is "In" engaged. If the Transfer case has been rebuilt, some mechanics leave the interlock out. If it seems to move with no problem in low but is hard to move in High. Your tire observation is a good one. 34" tall tires knocks the overall drive ratio down numerically. Your Jeep however has axle ratios that can handle that tire size without being to difficult to drive. If it is hard to move make sure you aren't dragging a brake. Also be sure the Emergency brake isn't sticking on, this can make it very difficult to shift it into gear.