so I got under there really quick on lunch and did hear much coming from either of the ujoints, I didn’t get much of a visual because it’s been raining all day here and I didn’t feel a ton like laying in it anymore so I’ll probably have another look and get those rears up.

I did get this coming from what sounds like the transfer case though. I listened super close and it’s definitely inside there. I’m guessing that’s the chain and I don’t know how much play it’s supposed to have but it sounds like a bit. Also keep in mind my case is mostly empty. I’ll drain it again here tonight or tomorrow and make sure there’s nothing super metallic, probably use my fishing magnet to try and get more out.


oh yeah the back brake plates are fkn toast on mine, there’s next to nothing left but there’s nothing touching, I thought that initially but I haven’t seen anything. I should check my rotors for scoring though!

I just replaced the diaphragm and cable and last I checked everything was engaging in the front end. I can very clearly hear the clicking engage from 4hi to 2hi so it sounds like that things doing it’s job. Good news is I found another tcase at the junkyard already pulled for $100 😂 if it does come down to it being that I’ll be happy to swap em and pop new seals and probably bearing in the salvage.

I appreciate the advice on that front shaft 😂 that actually seems like a super easy way to check that

 

So I dumped the fluid from my tcase and this was the condition. About to open her back up again for the leftovers, I’ll post that shortly if it’s anything exciting

 

I took my plugs out to drain the remaining fluid and it didn’t look too metallic. I’m really hoping some of those chunks in the video were rocks or mud from my undercarriage but there most definitely was a couple of shavings I could identify and clean my pans before and after using.

I THINK I MAY HAVE FOUND THE CULPRIT!



the heat shield on my fuel tank appears to be rubbing against my ujoint, must not have put the back on all the way when I dropped the tank to replace the pump hahahaha

Now the question is should I still drop the transfer case to replace that seal? I mean obviously yes but if someone can please help me understand why that seal blew out, is there something else I should be concerned about that I need to address when replacing the seal?

This is somewhat unrelated but also if anyone knows where I could get Splash Shields, I know I’ve seen a few older threads but I haven’t had much luck finding reasonable priced on eBay and to my knowledge no one makes them aftermarket

 

I don't think there is anything you can do to prevent the seal from leaking. It just seems to an issue of the seal hardening over time. It doesn't normally "blow out". If it did and went inside your transfer case, then I would definitely open it to see what other damage is in there.


Edit: Insure you use the proper fluids in your transmission and transfer case. There are cheaper routes, but I only use the proper GM fluids.

 

Can you just bend the heat shield back?

As for the transfer case, I cannot advise you on what to do although I'd be inclined to do what it takes to get it fixed.

And ditto for using the correct fluid from GM. And FYI, the 3-button and 4-button t-cases use different fluids.

 

Ok thats good to know, ill probably just fill it back up for now and get to it before summer. From what youre explaining it sounds like the tcase slowly fill up over time with a bad seal, at least that the more likely situation



Yup! shield bent back with a pair of vice grips really well

With the fluids I have the 3 Button and as I understand it that takes the same ATF as my 4L60E

 

Check your transmission fluid level also. I believe your truck originally called for Dexron III. I THINK it's now DEX VI. I could be wrong about that, so double check me with local GM dealership. Once again, I only use the GM product, so I splurge and get it from the dealership. But that's just me.

 

It is DEX VI. Im with you on using quality fluids but at this stage im still making sure everything works so once i confirn everythings not leaking or busted ill probably start replacing with quality fluids, until then im going economic

 

Had a chance to fill the tcase back up and take it for a drive, sounds gone so it was absolutely that heat shield. Definitely gained a lot of really great info from this and now I know I need to some some maintenance on that bad boy at least. Thanks again for everyone’s help that scared the hell out of me initially!

 

I also learned...I'll add "Check your gas tank heat shield" to the list if someone comes up with the same problem. LOL