Differential identification and oil quantity

[Tom Wright]

I acquired a 1957 CJ-5 recently and have started a frame off renovation. My manuals do not list the volume of oil for the Dana 27 and 44 differentials that the '57 CJ-5 originally had. Any suggestions for a good shop manual/ maintenance manual that would have such info in addition to just how to take parts apart? The front differential has no tag, and the only numbers I found were on the side of the ring gear "SALISBURY 17483 A3R55 43-8 G", and "16380" cast into the bearing caps, and "17038" in raised numbers on an outside case flange. Similarly, the rear differential had no tag, but had stamped on the ring gear "L 6 12 53 SAL 18530 B3R51 43 8 ", and "15388" cast into the bearing caps. Neither differential had "DANA" stamped anywhere, so I need enlightening on what these numbers mean and whether they are original DANA or replacements. I'd appreciate help in sorting this out. Cheers, Tom Wright

[Sebastian21]

You fill the differential to where you can just touch the oil with the tip of your little finger inserted into the fill hole. The weight of oil depends on the air temperature. Generally 90 weight in freezing conditions and 140 in warmer climates. I use the differential cover to identity the axle. There several charts on the Internet that show the covers for the different axles. The grease for the front hubs is 0 weight grease. It is a lithium grease. I am from old school they may have better multi purpose oil for the differentials today. Check with auto stores.

[LarrBeard]

We just batted the front hub lube issue around last week.

Google "knuckle pudding" for a lot of discussion about the stuff that goes in there.

Zero weight grease is probably a good technical description, but I recall one comment that it is rare and expensive. Corn head grease (local farm supply store) works well for light duty day-to-day use.

I was able to download several complete shop manuals for the trucks by googling model and year.

[Sebastian21]

For the front knuckles on a FC, same chassis as a CJ5, Zero weight grease is what the Jeep Service manual recommends. It is expensive at 35.00 per quart. It takes two quarts on each side. If the seals are good this filling will last 100,000 miles. That is on a Dana 44 spicer axle. I am unsure what FRONT axle a 57 CJ had when it left the factory. Many were changed so it could be anything now.

[gmwillys]

Here is a handy chart showing everything you need to figure out your axle configuration.

http://www.differentials.com/technical-help-2/differential-identification/

With the I.D. tag being lost to history, the easiest way to determine the gear ratio is to mark the ring gear and pinion with a piece of chalk on one tooth. Turn the ring gear one complete turn, till the chalk mark comes back around. While the ring gear is turned, count how many times the pinion mark goes around. If the pinion turns 4.11 times around, while the ring gear turns once, then it is a 4.11:1 gear ratio. Most older Jeeps are 4.27:1, 4.88:1, 5.38:1, or the later CJ5s started having 3.73:1 gears.