Transfer case Flange Nut Torque

[M37AJT]

I am replacing the seals on my transfer case and I notice in the TM to Torgue the Flange nut to 140-160 foot pounds of torgue. That sound like a lot of preload on the bearings.
Is that what it needs to be set to or I'm I missing something? Thanks for the help.

[just me]

Preload is set by the shims.
The 150 keeps the flange from falling off.

[M37AJT]

Thanks for the reply, My first post but I have been looking around for sometime.
So if you do not change the shims you need to torgue the nut to 140-160 feet pounds?

[Elwood]

Thanks for the reply, My first post but I have been looking around for sometime.
So if you do not change the shims you need to torgue the nut to 140-160 feet pounds?

Sort of two separate questions. The retaining nut on the yoke should be torqued to 140 to 160 lbs-ft. regardless if the shims have been changed or not. If, however, the bearing crush was incorrect, then the shims should be added to or subtracted from until the correct bearing crush is achieved before final torquing of the retaining nut.

[M37AJT]

Thank you for clearing it up for me!

[just me]

Actually, there is no crush in the transfer case. Preload is solely set by shims and if you don't open it up, they won't change. The flange torque is 150 and that is immaterial to the preload.

[Elwood]

Actually, there is no crush in the transfer case. Preload is solely set by shims and if you don't open it up, they won't change. The flange torque is 150 and that is immaterial to the preload.

I think we're talking about the same thing, I've just always used the word "crush" to describe bearing preload.

I'd agree that simply removing the retaining nut and the companion flange to replace the seal will not change the amount of bearing preload when the flange and nut are re-installed, since the shims have not been changed. If the bearing preload was not correct before the flange was removed, however, then it won't be correct when the flange and nut are put back on and torqued. However, I disagree that the torque on the companion flange retaining nut is immaterial to the bearing preload.

M37AJT, are you applying a Redi-Sleeve to that companion flange? Simply replacing the seal won't fix the leak if the flange is grooved from the old seal.

[M37AJT]

Thanks, Yes I installed redi-sleeve and one new flange due to being so bad.