Transfer case assembly fricka frack!

[OR VietVet]

I have an NP8 246 transfer case and the shift from reverse to drive and drive to reverse is noisier than ever and the case is wet at the back and I do not believe it is the output shaft seal. I am convinced I have the pin hole leak problems. I knew it would show up eventually and I have reached out to @915_Tahoe for availability. The reman part # is 24228420 and new part # is 24240015. You guys know me. I will put a new one in but I would assume a NOS part would have the problem in it that caused the pinholes in my old one. If the reman part has addressed the problem, I would prefer that instead.

Any input from members would be appreciated. I am not looking forward to being on my back swapping this out but I believe that it can be dropped without having to remove the crossmember for the torsion bars.

I had been hearing a metallic slight pop noise at the back area, that I was sure was a loose sway bar mount or trailing arm. I crawled under there and could not duplicate noise with my girl power braking in reverse and drive. I can pretty much make it do it when just pulling out end of driveway where it is bumpy. I see no loose attachments at trailing arms, sway bar, shocks, transmission/transfer case mount, cross member....etc. This noise is separate and I plan to lay a wrench/socket on everything back there and check tightness.

The transfer case leak/noise problem was found during the other noise inspection. Oh well, another post in my build thread coming up.

 

[strutaeng]

Have you checked your fluid level?

Pump rub? You are replacing the entire unit, right? Ask the supplier if the pump rub kit was installed. I would assume so, but why assume if you can simply ask them? They also sell aftermarket aluminum case halves that eliminate the magnesium case.

Edit: spelling :-(

 

[OR VietVet]

Level is low and I can see at least one pin hole. This transfer case replacement is gonna happen. Pump Run Kit? I will ask about that for sure. thanks.

 

[Fless]

Level is low and I can see at least one pin hole. This transfer case replacement is gonna happen. Pump Run Kit? I will ask about that for sure. thanks.

Pump RUB, not run. But the transfer case gets the runs...

 

[rockola1971]

I have an NP8 246 transfer case and the shift from reverse to drive and drive to reverse is noisier than ever and the case is wet at the back and I do not believe it is the output shaft seal. I am convinced I have the pin hole leak problems. I knew it would show up eventually and I have reached out to @915_Tahoe for availability. The reman part # is 24228420 and new part # is 24240015. You guys know me. I will put a new one in but I would assume a NOS part would have the problem in it that caused the pinholes in my old one. If the reman part has addressed the problem, I would prefer that instead.

Any input from members would be appreciated. I am not looking forward to being on my back swapping this out but I believe that it can be dropped without having to remove the crossmember for the torsion bars.

I had been hearing a metallic slight pop noise at the back area, that I was sure was a loose sway bar mount or trailing arm. I crawled under there and could not duplicate noise with my girl power braking in reverse and drive. I can pretty much make it do it when just pulling out end of driveway where it is bumpy. I see no loose attachments at trailing arms, sway bar, shocks, transmission/transfer case mount, cross member....etc. This noise is separate and I plan to lay a wrench/socket on everything back there and check tightness.

The transfer case leak/noise problem was found during the other noise inspection. Oh well, another post in my build thread coming up.

Tcase Drive Chain could be stretched and smacking the inside of the case. Eventually it will chew through it. If you want to save some money a new chain runs around $100 and the pump rub plate use to cost around $30 and you can get them on amazon and ebay. You can buy a replacement rear half housing to replace yours too. You will need long nose internal/external snap ring pliers. The Tcase is very easy to take apart. What kinda cost are you looking at for a reman one?

 

[OR VietVet]

I have priced a reman t-case, rebuild mine with the components you mentioned, $695 and I would be taking out and reinstalling.

Yesterday I crawled under and sprayed down the back half of case and found no pinholes. The output seal has a factory seep hole on the little collar/boot that is around the driveshaft snout. I squeezed from both sides and pushed down and no fluid came out. I am going to drive for a week and then put the Tahoe back up on ramps and look at the case and see where the fluid is coming from. It was never drips. It is seepage of some sort.

 

[OR VietVet]

I am not looking forward to the t-case removal. It looks like can work it out of there without removing the torsion bar cross member but the removal and reinstall is much quicker if go ahead and remove the cross member. That is not work I am looking forward to, laying on my back. If and when I do this, I think I am going to get a reman unit and pay my friend for use of his tools and lift at his shop, on a weekend. That way it is a straight swap out. Then I can either return the old t-case for core or keep it and open up and repair as needed and sell here locally. I have never had a t-case opened up and worked inside.

 

[rockola1971]

I am not looking forward to the t-case removal. It looks like can work it out of there without removing the torsion bar cross member but the removal and reinstall is much quicker if go ahead and remove the cross member. That is not work I am looking forward to, laying on my back. If and when I do this, I think I am going to get a reman unit and pay my friend for use of his tools and lift at his shop, on a weekend. That way it is a straight swap out. Then I can either return the old t-case for core or keep it and open up and repair as needed and sell here locally. I have never had a t-case opened up and worked inside.

A Tcase is very easy to work on...Once you get it out from under the vehicle. There really isnt a whole lot to them. They are not even remotely complex as an automatic transmission. They can be rebuilt in an afternoon as long as you have a set of the long nose internal/external snapring pliers, bearing and seal driver set. Everything else is common tools and a freezer to stick the bearings in the night before you want put Tcase back together.

 

[rockola1971]

I am not looking forward to the t-case removal. It looks like can work it out of there without removing the torsion bar cross member but the removal and reinstall is much quicker if go ahead and remove the cross member. That is not work I am looking forward to, laying on my back. If and when I do this, I think I am going to get a reman unit and pay my friend for use of his tools and lift at his shop, on a weekend. That way it is a straight swap out. Then I can either return the old t-case for core or keep it and open up and repair as needed and sell here locally. I have never had a t-case opened up and worked inside.

 

[George B]

I have removed and installed the transfer case on an 03 Burb without removing the crossmember. It’s not so bad. Just gotta turn it sideways and it drops right out.

 

[OR VietVet]

After I got in there with a couple cans of brake clean and cleaned the entire rear half of transfer case, I can see what I thought was a pin hole and is not. I am going to look at it again in about a week. I am convinced that the output seal is not leaking.

 

[Fless]

Here's a bit more of a hint of where to look for the pump rub pinhole, courtesy @rockola1971:

Transfer case whine

I have a 2002 Tahoe and the transfer case whines while in 2high, it gets quieter while under a load and goes away when shifted into 4high. Seems like the chain could be stretching and whining while not under a load. I am capable of rebuilding the transfer case myself, but there are so many...

www.tahoeyukonforum.com

 

[strutaeng]

After I got in there with a couple cans of brake clean and cleaned the entire rear half of transfer case, I can see what I thought was a pin hole and is not. I am going to look at it again in about a week. I am convinced that the output seal is not leaking.

Maybe add some UV dye and check again?

 

[rockola1971]

Check red dot marked area all the way around rear case half. Yellow circle marks an actual pump rubhole. Check that area all the way around the case. For some reason the rubholes almost always end up on the passenger side of the case rear and usually on the top half.

 

[InterceptorF]

You can replace the T-case without removing the torsion cross-member. It is easier with two people (and your tongue sticking out to the left .

 

[OR VietVet]

Just last week, I crawled under and everything was dry. No leakage so far and plan to check every week. Level ground and the "blue" fluid was right at the bottom of the fill hole. No noises recently. Crossing fingers. My other noise over bumps and undulations was a loose nut on the attaching bolt for the right rear sway bar link. Tightened both sides down and no noise. The T-case swap is on hold for now.

 

[V327839]

I have removed and installed the transfer case on an 03 Burb without removing the crossmember. It’s not so bad. Just gotta turn it sideways and it drops right out.

I second this. I don’t look forward to it either, but I did it by myself on my back in the driveway. Remove the tcase mount and let it rest on the crossmember to get enough clearance for the top bolt. And get a super shorty wrench.

 

[OR VietVet]

Here we are 3 months later and still is dry. I have no idea what I thought I saw before. All fluid levels good and look fine.