Flapping noise in transfer case or ?

[ccallaway]

I have a 1959 CJ3B. I recently rebuilt the engine and everything has been running fine.

Last weekend while driving it around the deer lease, while in 1st gear (Hi) there was a flapping noise in the transfer case or transmission. I crawled under the jeep to determine if anything was hung up in the drive shaft(s) and found nothing.

It will drive fine. It does not make the noise in 2nd or 3rd gear (Hi). It does not make the noise in 1st, 2nd, 3rd (Low).

Anyone have any thoughts as to what is wrong and what I should do?

Corey

[gmwillys]

Welcome ocallaway,

Is the noise being made while under power, (acceleration/deceleration/steady speed/ or all the time? Is there any unusual vibrations noticeable at the shifter when the noise is present? Are the transfer case shifters traveling the full range of movement? A tight/dry U-joint can make a similar noise as to what you are describing.

The first order of business would be to drain the transmission/transfer case. This will not determine where the noise is coming from exactly, because it is a shared oil reservoir between the two, but more of a check for metal or water contamination. I have placed a heep up on sturdy (6 ton) jack stands, and have ran it in gear while crawling up underneath to listen/ watch for leaks. I don't recommend this action, there are bad things that could happen in a hurry. The next check would be to pull the shift tower off of the transmission. Inspect all the transmission gears, and ensure the intermediate shaft is not rusty.

[ccallaway]

The noise occurs while driving, under power.

No vibrations.

I believe the shifters are fully engaged, full range of movement.

Thank you for the input.

Corey

[gmwillys]

No problem.

No vibration and no noise during deceleration are good signs that there isn't anything major wrong. I would still pull the oil out and check for any debris to ensure there isn't anything being eaten. Keep us advised of your findings. I'm interested to know what exactly is going on.

[ccallaway]

I am going hunting this weekend. I will tinker around with it when I am not hunting on Saturday.

[LarrBeard]

I am going hunting this weekend.

Let's hope it's a wad of grass or a piece of stump struck somewhere. Won't be the first time ...

[gmwillys]

Good luck on the hunt for both critters and noises.

[ccallaway]

I continued to drive the Jeep thru hunting season. The flapping noise continued off and on through out the season. I did finally change the gear fluid. Yes, it did have water contamination. There were very fine metal flakes in the fluid. This weekend I will take a look at teh shift tower.

[gmwillys]

Keep us informed. I'm curious to learn what you find.

[LarrBeard]

"... There were very fine metal flakes in the fluid. ..."

As the Old Perfesser used to say; "Uh - oh ".

Now, the biggest question - did any critters get to go for a Jeep ride?

[ccallaway]

I took the tower off, no rust. I cannot determine anything. But the IN / OUT for high and low is stuck and I am stuck in low. The Jeep runs and, drives fine, I can shift through the gears, but at this point, I am stuck in low. Yesterday when I drove it and parked it I noticed a large puddle of watery oil. I thought when I drained the transfer case that would include the transmission.

I stuck my head under the jeep and find the transmission drain plug is missing, located at the very bottom of the transmission. I searched around where I drove and did not find the drain plug. I have never taken it off. But there is probably no fluid left in the transmission.

New question, Will the transmission fill plug part number 5140A fit?

[ccallaway]

Oh, and there were no critters riding in the jeep.

As to hunting season, one 7 pt buck, one doe, two pigs and a coyote.

[gmwillys]

Ocallaway,

The fill and drain plugs are the same, and can be picked up at any hardware store. NPT 1/2" pipe plug

Included is a good diagram of the parts breakdown of the transmission;

https://www.cj3b.info/Photos/Parts/Transmission.jpg

Your T-case being stuck in low is a common issue. A lot of original Jeeps have had a hole knocked into the passenger side trans tunnel for the application of a pry bar to help the shifter move. My advice is to spray some PB Blaster on the pivot pins of the shifters, and the shift rails going into the transmission. If you apply pressure from underneath the Jeep, ensure that the wheels are chalked. Reason being, if you are up underneath, and you get the shifter to move, you will find neutral before hitting high range. Just a word of caution. Stopping a rolling Jeep with your foot doesn't feel that good.

[ccallaway]

Thank you for the info. I will keep tinkering.

[ccallaway]

The diagram, I thought that was the transfer case. I see the diagram says transmission, but the plug was missing, and fluid was dripping from a housing in front of (towards the engine) that looks like the transmission to me.

[gmwillys]

Included is the diagram for the transfer case;

https://www.kaiserwillys.com/diagram/cj-3a-diagrams/transfercase-diagrams-willys-cj-3a/dana-18-transfercase/dana-18-transfer-case

Being that the transmission and transfer case are "married", the transfer case envelopes the transmission, since it is pretty much twice the size. The transfer case mounts to the rear of the transmission, while the transmission mounts to the bell housing of the engine. Both share oil, but since the T-case sits lower, it retains oil when the transmission is low on oil.

Hopefully this will help clear the muddy water? Included are some pictures with the body off;

[ccallaway]

Thank you again.