Replacing rear differential and transfer case bolts???

[watershipdown]

I am getting ready to change my rear differential fluid and transfer case fluid. I remember reading somewhere that you are supposed to (according to GM) replace the bolts for the diff. cover and not reuse the old ones, also they say to replace the transfer case drain and fill plugs. Anyone know why or if I really need to get the new bolts or plugs , or will it be alright to reuse the old ones.

they say to use a sealant on the transfer case plugs, what kind of sealant should I use, I am thinking probably just some teflon pipe sealant but just want to make sure.

Thanks for any help you guys can give me!!!

 

[Chris142]

"Replacing" the transfer case drain and fill plugs means to screw the old ones back in the holes.

I don't see any reason to replace the bolts that are in a low stress place like a diff cover unless they are damaged.

I'd use Teflon tape.

 

[watershipdown]

The reason I said replace was that I read on a chevy trucks forum and they had an article on how to do it, the guy doing the service said that he bought new bolts and drain plugs because GM said not to reuse them. I don't see any need either to replace them. Thanks for the responses guys!!!

 

[MolaKule]

You may want to replace the sealing washers on the drain/fill bolts, but replacing the drain/fill bolts (assuming steel) is riduculous.

 

[VaderSS]

There are some bolts which are not meant to be reused, but I don't know if this one of those cases.

The swaybar bushing bolts on my Impala are a one example. Not replacing them almost assures that you will strip the frame threads. Course, most don't replace them with the stock style bolts, but use a standard bolt which can then be reused...

 

[MolaKule]

On my Nissan Frontier, the only bolts that need replacing are the driveline Flange bolts for the flanges that connect to the U-joints, since the removal of same compromises their strength due to high removal torqueing.

I see no reason to replace diffy cover bolts that have a tightening torque of approx. 25 lb.-ft., or drain/fill bolts that require about the same or less.