[UTEngineer]

Finally had a local transmission company pull my transfer case and open it up with only 38k on my odometer. They called me today and said the chain and several sprockets inside the transfer case are trashed.

Said they don't normally see this kind of damage, especially with only 38k on the odometer, but this is the first 2017-2019 L5P transfer case they have opened up. (they also said it is basically an MP1626XHD model transfer case with some upgrades parts ... so they are very familiar this transfer case and have rebuilt hundreds of similar transfer cases, just not this new)

I told them to take pictures and forward me the parts list ... and let me know what they think caused the damage when they take it apart. (part failure, improper assembly, etc.)

Backstory

My truck has had a vibration in 4wd under load (when accelerating) since I purchased it brand new off the Chevrolet lot (September 2018).

Therefore this is an ongoing concern which I brought up to the dealer during multiple visits to their service department at ~12k, ~24k, & ~37k ... basically each winter when I once again used 4wd.

I even have the documented proof (warranty invoices) proving the truck was brought into the local dealer multiple times regarding the vibration complaint, including before any aftermarket parts were installed on the truck. (lift kit was installed at ~26k, after the first two warranty complaint visits)

The first two times I took it to the dealer they gave it back to me and told me these trucks are just noisy in 4wd. I believe the second time I brought it in they actually checked the front driveline for play and said it was within spec ... but unfortunately they never did run the truck in 4wd under load while up in the air and listen to the transfer case with a stethoscope (which I actually asked them to do). The third and fairly recent visit to the dealer they said there may be something wrong with the transfer case but they can no longer look at it under warranty because the truck now has a 4 inch lift kit on it.

Again, I have all of this documented on warranty inspection invoices from this local Chevrolet dealer.

I was however able to finally get a case number out of GM customer service today and an email where to send the pictures for review.

However, I am not getting my hopes up that GM will even reimburse me for this out-of-pocket expense, which should truly be covered under the 100k powertrain warranty.

Luckily the lift kit I purchased also offered a powertrain warranty if GM does not cover the repair, so I got lucky because I am covered regarding any out-of-pocket expenses on this transfer case repair.

Apologize I don't have the pictures of the transfer case internal parts failures from the transmission shop yet, but I will follow up this post with the pictures as soon as I receive them (hopefully tomorrow).

So for all of you out there with similar pictures to mine regarding excessive amounts of metal on your transfer case magnetic drain plug when changing the fluid ... beware ... you could have a major powertrain failure on your hands just like mine.

Pictures below are at 25k & 35k miles when changing the transfer case fluid ... according to the local Chevrolet dealer ... this is normal ... LOL.

 

[viper8315]

oh man, sorry to hear UT. Well, hopefully you do get it warranty repaired. If not, good excuse to upgrade it if there's even anything better on the market.

 

[UTEngineer]

oh man, sorry to hear UT. Well, hopefully you do get it warranty repaired. If not, good excuse to upgrade it if there's even anything better on the market.

I am extremely lucky ... my lift kit provides a no deductible powertrain warranty ... so I am covered either way.

If GM does not step up and do the right thing ... my next truck is not a GM product ... which is sad because I have been a lifetime loyal customer.

I am more worried that others, especially on this forum, who have also shown similar pictures of the excessive metal shavings & particles on their transfer case drain plug, may also be part of a significant powertrain failure and a future class action lawsuit against GM.

Yes I am glad I am covered ... but not happy about this kind of major powertrain failure brand new off the Chevrolet lot.

But you are right ... when the transmission shop is done rebuilding it ... I will have a better built transfer case than what I got new from GM.

Headed back home to SLC tomorrow and will gather the part failure pictures myself and post them on this thread.

More to come ...

 

[duecedriver]

I am extremely lucky ... my lift kit provides a no deductible powertrain warranty ... so I am covered either way.

If GM does not step up and do the right thing ... my next truck is not a GM product ... which is sad because I have been a lifetime loyal customer.

I am more worried that others, especially on this forum, who have also shown similar pictures of the excessive metal shavings & particles on their transfer case drain plug, may also be part of a significant powertrain failure and a future class action lawsuit against GM.

Yes I am glad I am covered ... but not happy about this kind of major powertrain failure brand new off the Chevrolet lot.

But you are right ... when the transmission shop is done rebuilding it ... I will have a better built transfer case than what I got new from GM.

Headed back home to SLC tomorrow and will gather the part failure pictures myself and post them on this thread.

More to come ...

Lift kit should have nothing to do with a tcase. Diff maybe. Half shafts absolutely. Running much bigger tires possibly due to the additional torque maybe.

they told you what parts failed but did they take a stab at failure mode? Why did it happen. Because if they don’t fix they why it will just happen again potentially.

 

[gmc502]

that sucks about the transfer case.I remember way back,my 02 lost the transfer case,,got a reman from gm.it lterally lasted 2 weeks before it ground itself up.sad to see hey haven't gotten any better.at least the replacement one is still going.

 

[HighLinerMI]

Better check mine, I have the same vibration and have purchased the Cognito driveshaft in hopes it’s an angularity issue.

 

[duecedriver]

Better check mine, I have the same vibration and have purchased the Cognito driveshaft in hopes it’s an angularity issue.

Does your kit lower the front diff?

 

[HighLinerMI]

Yeah I have a 5” Zone lift

 

[J5ady]

Now I wanna check mine. Been kinda rough on her lately....

 

[duecedriver]

does the top fill plug have a magnet as well or just the bottom drain plug..

I have not even looked at the T-Case on mine yet?

I know the magnesium case on my tahoe had some very specific torque specs and special sealants for the threads to keep from cracking the case and getting bi metal fusion..

anyone have the tech procedure for servicing one of these T-Cases...?

 

[UTEngineer]

Lift kit should have nothing to do with a tcase. Diff maybe. Half shafts absolutely. Running much bigger tires possibly due to the additional torque maybe.

they told you what parts failed but did they take a stab at failure mode? Why did it happen. Because if they don’t fix they why it will just happen again potentially.

Bad bearing ... lateral side to side movement of the inner race was causing the chain to move laterally back and forth on the sprockets ... which was starting to wear improperly on the outside edge of the sprockets.

Got pictures on my phone of the parts ... will attach them to this string later tonight or tomorrow.

“China“ stamped right on the sprockets ... sourcing of cheap parts from China ... go figure.

 

[duecedriver]

Bad bearing ... lateral side to side movement of the inner race was causing the chain to move laterally back and forth on the sprockets ... which was starting to wear improperly on the outside edge of the sprockets.

Got pictures on my phone of the parts ... will attach them to this string later tonight or tomorrow.

“China“ stamped right on the sprockets ... sourcing of cheap parts from China ... go figure.

say its not so.... cheap chinese parts... color me all kinds of shocked.. .hehe

 

[UTEngineer]

say its not so.... cheap chinese parts... color me all kinds of shocked.. .hehe

First pic is a failed bearing with lateral movement of the inner race which was causing the side to side movement of the chain. Other pics are the sprockets where your can see the “onion peel” wear on the outside face of the gear teeth in the upper addendum area. In fact, you can also see the top land edge wear from the top view as well.

Side Note: Zoom in on the sprocket on the upper left of the first pic and you will see the “CHINA” stamping.

 

[ChevyTech77]

Any correction/change made to the front driveshaft, and/or it’s working angles, for the front diff drop?

 

[Noble_dmax]

Always thought that mine made a whine/ strange noise in 4x4, particularly from the passenger side, when going at speed down the road... very interesting.

 

[AlisoBob]

Thats just fugg'in sad....

I run 0w/16 motor oil in the TX case on both my LML and LLY.... no more fuzzy magnets

 

[AlisoBob]

LML TX Case Fluid.....

Most of you know I have 2 Dmax's, a LLY and a LML. I treat them both the same, with the exception of the transfer case oil. For the last 200k miles I've run motor oil in LLY. I service it about every 30k miles ( depending on how it falls into the engine oil change schedule). The oil always looks...

www.duramaxforum.com

 

[viper8315]

oh man, well, to use a famous phrase:
Gentlemen, we can rebuild it. We have the technology. We have the capability to make the world's first bionic transfer case. @UTEngineer 's will be that transfer case. Better than it was before. Better... stronger... faster.

 

[duecedriver]

oh man, well, to use a famous phrase:
Gentlemen, we can rebuild it. We have the technology. We have the capability to make the world's first bionic transfer case. @UTEngineer 's will be that transfer case. Better than it was before. Better... stronger... faster.

But it will cost 1 milllion dollars...oh wait that was the ‘70s.
it will be the 1 billion dollar transfer case

 

[UTEngineer]

Any correction/change made to the front driveshaft, and/or it’s working angles, for the front diff drop?

The front differential was rotated such that the pinion yoke points upward / straight at the transfer case front output shaft ensuring a zero degree u-joint operating angle at the differential end of the front driveshaft.

This was accomplished by carefully measuring, calculating & fabricating the appropriately angled front differential drop brackets.

I also purchased & installed a high quality double cardan driveshaft specifically designed for a 2017-2019 2500HD or 3500HD 4x4 Duramax 4-inch differential drop lift kit to significantly reduce & improve the u-joint working angles at the transfer case end of the front driveshaft.

We even carefully drilled and tapped a strategically placed gear lube overfill hole in the front differential housing to allow for easy overfilling with anti-foaming Redline 75W-140 gear oil to ensure the 4.56 ratio Yukon pinion is not starved for lubrication.

Honestly, I am yet to see the front end of a differential drop lift kit on a 2017-2019 Duramax crafted as carefully & meticulously as this setup.