Transfer Case Rear Output Preload

[sturmtyger380]

I am to the point on my truck of replacing seals on the Transfer Case. Awhile ago I bought a set of bearings for the TCase from DC Trucks in Oregon.

Opening up my TCase it looks really good inside so I had planned on not changing the bearings. In putting it back together I got to looking at the rear output bearings and the race had these strange colored spots in the metal. I could not feel anything rough but it just looks like the bearings go really hot. So I decided to use the race and roller bearings I got from DC Trucks. The bearing and race numbers match.

I removed the races and the large cone from the gear and shaft. Pressed on a new large bearing and assembled it back together with the original shims to check the preload.

It didn't have enough preload. So, I took it apart and removed some shims. Still not enough preload. I kept removing shims until I got down to none, only the spacer was left. Still I can only get up to about 50 inch pounds of resistance when torqued down. I should be getting at least 180 - 360 inch pounds = 15 - 30 foot pounds.

I can pick the assembly up and tilt it back and forth and hear the spacer sliding back and fort between the large and small bearings.

What am I missing here? To me with no shims the assembly when torqued down should not be able to turn.

[mike_m]

Double check that torque spec. I did this many years ago but I recall the spec. being around 24in-lbs not ft lbs.

Good luck

MikeM

[sturmtyger380]

Well that was interesting - In the body of the manual I have for adjusting the preload of the output shaft bearings it says 15 - 30 pound-feet torque. Later for the brake output shaft it says refer to the rebuild standards section for preload.

In the same manual down in the Repair and Rebuild Standards it says for both the brake shaft bearings and the rear axle output shaft bearings 15 - 30 lb-inch torque.

I guess the body has a typo.

Last night while watching some of the crazy football games I decided that today I would start over and add too many shims to make the assembly loose and then remove shims until it gets to the correct preload.

[John Mc]

I guess the body has a typo.

There are a number of those scattered throughout the manuals. I found one place where the names of the idle mixture and idle speed screws are reversed. (Fortunately, that's a simple one to figure out if you just stop to look and think.)

[NAM VET]

long years ago, when I was in the army, I learned that TM's back then were written for someone with an 8th grade education using them. Actually, I think they were also written and proof-read by someone with an 8th grade education. TM's would come with "change 1" sheets or lists of errata, but these usually were promptly lost 

NV

[sturmtyger380]

All is good now. I got the output side done and sealed up. I put all the original shims in plus an extra one for good measure.

It was loose and I could pull the flange in and out. I took out the extra one and had the original set of shims - not enough preload. The inch pound tool barely got to 5.

I removed the thinnest shim and reassembled, now we were just up to 30 inch pounds. I stopped there as the bearings are new and will probably loosen up. Now on to the parking brake output.

[John Mc]

long years ago, when I was in the army, I learned that TM's back then were written for someone with an 8th grade education using them. Actually, I think they were also written and proof-read by someone with an 8th grade education. TM's would come with "change 1" sheets or lists of errata, but these usually were promptly lost 

I wonder if anyone has copies of the "change" sheets for the more popular manuals. It would be great to be able to go through and mark the manuals so I have a heads up if I am ever using that section.

[Elwood]

The most recent change list for TM 9-8031-2 that I've found is C9 "Corrections and Additional Info", dated May 1965. I think I bought my copy from Portrayal Press, but I don't see it as a separate item on their website. Maybe it was bundled with the manual when I bought that one.