Transmission Case Failure

[admzn]

I was noticing a lot of movement in the transfer case shifter on my 2002 Xterra. Motor mounts were solid so it had to be the transmission mount, right? I pulled the skid plate to check and found this... Thought it was interesting enough to share. Talked to a friend who works at Nissan and he said they used to replace them under warranty occasionally.

Luckily this transmission was used in the 2wd version as well as the 300ZX so the extension housing (where the bracket is) is removable. Got a new one coming in but not looking forward to dropping the T-case. And the amsoil ATF in there only has 10k on it... oh well.

New to me part is on the way:

 

[KGMtech]

Well 18 years, but was there any event that might point to the fracture?

 

[mattd]

Looks like oxidation got it. For a high stress point the aluminum is not very thick there either.

 

[admzn]

Well 18 years, but was there any event that might point to the fracture?

I do take it off-road regularly, but am not the type to be aggressive on the throttle. After a trip I noticed I could feel the torque converter lock/unlock at low speeds, it jolted the cab. I thought that was weird, and then noticed in 4wd low range, the shift lever really moved. I checked a local scrap yard and the trans in the one Xterra there looked like it was starting to crack too.

Looks like oxidation got it. For a high stress point the aluminum is not very thick there either.

Yeah it is pretty thin, and you can see where the bolt goes it is all corroded, too. I am the 2nd owner and the first one did not seem to take much care with regards to washing or rustproofing. But steel bolt, aluminum, add salty winter roads and it's a good recipe.

Here is another view:

 

[Racecarfan2]

Replace all the mounts or it will break again. That should not be under stress.