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Transfer Case Pump Rub Through Housing

tak1973

Full Member
Joined
Feb 23, 2009
Messages
32
Location
Owasso, OK
I've got an '03 1500 with about 114,000 miles on it.  I'm chasing down a front end noise that I believe to be the CV shafts.  Since they are relatively inexpensive, I'm just going to replace them both.

While looking into drive train problems, I have come across stories about this transfer case issue.  I've read a lot  of horror stories on the net about this transfer case rub problem.  I'm trying to get a feel for how many people really have problems with this.  If it's pretty common, I'm considering installing the pump upgrade kit.  If it's not, I'm not sure I'm gonna worry about it.

How many instances of this have y'all heard about?  Is it more of a problem with the 1500s or 2500s?
 
Yes it is common all right, the oil pump rubs a hole in the case.
 
I have JB Weld covering the hole in mine right now! I'm looking for the output side of the transfer case now along with the pump upgrade kit.

If you have time and $$$, plan on catching yours early! With that mileage, it's probably pretty thin by now. Mine was noticeable at 145K miles......
 
lurchsavalanche said:
I have JB Weld covering the hole in mine right now!

  Same here at 175000 on a 2003 2500. Seems to be holding O.K., but I'm looking for spots in the driveway every time I get into the truck.  A very poor design on the transfer case.
 
It only happens if the clip falls loose. Look for it in the bottom. Listen for the pump hammering the tailshaft housing. Look for signs of the holes developing. I'm not sure I would pull it apart if I did not see some indicators. I have one that I repaired in the warehouse. Less than 100k miles on it.  Same thing, replace the clip and fill the holes with JB Weld. I have another with over 200k on it and no signs of trouble. It is a roll of the dice.
You are all correct...poor design :(
 
My 2007 Z-71 just had the hole rupture from the pump rub at 59,900 original miles 12/3/13!  You bet it's an issue!  I read up about it first, called a local transmission shop to find out what it would cost to repair outside of a dealership and was told about $700...I took it to my dealer as my 6 year warranty had expired nine months earlier.  I explained my disappointment with GM not bothering to let me know in anyway of this impending doom....lucky I didn't burn up my transfer case on my 300 mile trip towing a jeep behind me. The service rep advised he would contact GM on my behalf and inquire about possible assistance...I was offered a good will cost of a $350 dollar deductible to pay towards the total repair which I was happy to pay....(I was told the repair with labor was around $1500 at the dealer). They are putting on a new rear case and modified GM parts that are supposed to cure this problem...It could have been a lot worse, shame on GM for not issuing a TSB to customers on this issue....I could have had it corrected when my warranty was still in effect.
 
i believe there is a tsb on this .. mine is starting to make noise back there where it is rubbing (112,000 miles) .. dont know what i will be looking at till i open it up but right now the parts (not a new housing just upgrade kit) im looking at $125 in parts and a case of beer for an extra set of hands  :D

 
Just found a hole in my case, 03 with 106,000 mi.  I'm pretty sure mine ran dry since I heard some nasty noise when I put it in 4 high last time.  I've warned everyone I know with a chevy to look for this issue and get a case saver. 
 
when i pulled mine and took it apart there were no signs of rub but i did put in the upgrade kit while i was in there  (y)
 
very common problem... happened to me as well.  my fluid leaked all out and it starts making ticking noises...  they are hard to hear if you don't have the windows down.  I paid $1500 for local shop to fix.
 
Sorry to say it will happen with the clip sill there. I bought a used t-case pulled the end case off to install the case saver and it had a hole under the clip. That is what happens when you have a harder material hitting a softer material. Case Magnesium - pump Aluminum. Some times there is no sings it is leaking it only comes out when the truck is in motion that is when the pump works and it blows back and does not always drip when parked.  So that is how a lot of t-cases get burned up.
So unless you have aluminum case its not if it is when.
There is another weak spot on the rear case the retaining clip wears on the case and sometimes brakes. A must spot to check over when you have the case apart if you are not replacing the rear case.

 
I'd say you're asking for trouble by not putting the plate in.  You can do it yourself with basic hand tools.  Replacement transfer cases are expensive and a plate is cheap insurance.  I caught mine in time, and had I not it'd of cost me a grand for a rebuilt case.  Instead I spent 50 bucks.  Your call.
 
Merchant automotive guarantees that if you have their upgraded pump kit ( which is quite a bit different ) and your transfer case fails to pump rub they will replace your transfer case... I would say that by putting it in I avoided future damage
 
wyotonka said:
Merchant automotive guarantees that if you have their upgraded pump kit ( which is quite a bit different ) and your transfer case fails to pump rub they will replace your transfer case... I would say that by putting it in I avoided future damage
(y) X2
 
Didn't catch mine in time.  Have a hole now and the Merchant kit on the way.  JB weld is holding as a temp solution.

This was on my list as a preventative measure, but didn't get there in time.  My truck has about 128k miles on it now.
 
Does anyone have pictures of where to look for the rub through? What noise does it make? I have a ticking noise that varies with drive train speed but is very inconsistent. I'm thinking u-joints, but I want to inspect the tc tomorrow. I just bought this 04 used, so I don't know the history.
 
No noise unless it's been leaking and all the fluid is gone and it's damaged..

To see pictures just do a search in the internet for "GM transfer case pump rub" you'll find a lot of pics and info..
 
Aerohokie said:
Does anyone have pictures of where to look for the rub through? What noise does it make? I have a ticking noise that varies with drive train speed but is very inconsistent. I'm thinking u-joints, but I want to inspect the tc tomorrow. I just bought this 04 used, so I don't know the history.
216d1260928569-transfer-case-leak-pump-rub-dsc01359-copy-small-.jpg
Mine had no signs of rubbing when I pulled it apart, if you go through that much trouble, take a little time and put the upgrade in, it is a much better design IMO.
 
A couple of notes from my experience:

1) you might need a mirror to find the hole as it was above the midpoint of the case when you have crawled underneath the vehicle.
2) the hole looks like a small slit rather than a circular hole.  It almost looks like it was machined and intentionally put there.
3)  Mine ran with no fluid in it for a while (maybe a couple of months) before I figured all this out and AFAIK it will take a while to damage it.   I did hear a *FAINT* clicking noise when moving.  The noise went away when I refilled the fluid.  Leaked out again, and I heard the noise again.  Got it repaired years ago and no further trouble.
4) I tried JB as well...  twice.  Could not get it to bond leak-free due to my inability to properly clean the oil out of the area and/or rough up the surface a bit.  JB weld is not as strong as the case either, so if the clip continues to rub against it, it will just file down your JB patch in a hurry.    If you fixed the internal problem AND use JB weld, it would probably be a good fix, however, it takes a while to take the case off and apart so its really not worth taking the chance of having to do it twice.



 
Thanks for the pic, I'll check. My ticking is very loud and varies with wheel speed not engine speed. Strangely no clicks at all in the rain. Still thinking u-joints. I get it on the rack tomorrow.
 
dunno how often a u joint goes bad on these trucks, but wheel bearings fail all the time.  I would be checking that first by jacking up each tire and checking for side-side play.
 
The clicking is loudest when I start from a stop. It stops as soon as I take my foot off the gas. It's also very inconsistent, yesterday it didn't do it all, today twice, 2days ago it did it a dozen times. I had the vehicle aligned today, no discrepancies with the wheels were noted. I did find JB weld on the transfer case though, so there's that.
 
Aerohokie said:
The clicking is loudest when I start from a stop. It stops as soon as I take my foot off the gas. It's also very inconsistent, yesterday it didn't do it all, today twice, 2days ago it did it a dozen times. I had the vehicle aligned today, no discrepancies with the wheels were noted. I did find JB weld on the transfer case though, so there's that.
I would say check your Ujoints, they make a lot of noise that isn't easy to pin down because of the hollow drive shaft. I have replaced mine 3 times in the 6 years that I have owned my truck, once they made a vibration, once they were squeaking, and once they were clicking when they went out... they're very inconsistent lol. These trucks are heavy and if you do any offroad I feel like it's worse on the Ujoints, they're pretty quick and painless to do though.
 
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