I did something stupid today. I was at a truck pulling contest today and my truck was REALLY bouncy. I was trying new tires and it seems the sidewalls were too soft probably.

Anyways I kept going and bouncing I BROKE MY ALU DRIVING SHAFT.

I have a few questions related to that event.

1- Can they be rebuilt (tube changout) or do I have to buy a new one?

I went home in 2WD but I noticed some Dextron leak coming from between the TC and the ALI that wasn't there before. I addition, after a few miles in 2WD I began to feel something skipping from time to time. It "seamed" to come from the TC but I'm not sure. I felt a small jerk while rolling. The last few miles I made them at idle not to agravate anything. When I put it in RWD, it doesn't move of course but I able to shift the five gears, the output from the TC turns and theres no jerk.

2- Any ideas about what could be causing that skiping sound?

Thanks for your help.

How did you go home in 2wd if you grenaded your rear driveshaft?

1- Get a new one, has the universal joints are probably shot or weakened.

2- No TC expert but doesn't look good. I'd change the oil to see if the are metal shaving or else...

Bonne chance.

Daniel.

How did you go home in 2wd if you grenaded your rear driveshaft?

2WD with the front wheels only.

1- Get a new one, has the universal joints are probably shot or weakened.

One of them is weakened. They cost 20$ at NAPA and are easily changed. I would rather put 2 new U-Joints and save a few hundreds on the driveshaft.

2- No TC expert but doesn't look good. I'd change the oil to see if the are metal shaving or else...

I'll do precisely that tomorow morning.

Thanks.

ok corection for you.... you drove home in 4WD with no rear driveshaft.... therfore only being propelled by the front tires... the way you stated it confused me for one

second... (just for refernce)i've seen many a rear axle break teeth or spyders... and not act up with it spinning with no load(i.e. jacked up off the ground) so your t-case could be hurt but you won't know it until you actauuly get the rear drive shaft installed and put a load on the setup....

on a side note.. the rear output of the t-case basicly a "straight through" unless you put it in low range so its more likely your front output would be hurt (like a broken chain or broken sprokets etc.)(not personally sure if these cases are chain drive or not so forgive me if i'm mistaken) hence the lack of noise when its in 2WD not putting any power to the chain...

Also check your front drive line for broken u-joints maybe you have one that only boke one corner and its still intact but messed up and may only make noise under the corrct load!
just a shot in the dark but maybe you'll be lucky!!

I drained the TC this morning. Since it was leaking (see note 1), only half a cup of DIII came out. I didn't see any metal shavings BUT something came out of the drain... It looked like molted resin or a blotch of glue. Any ideas where that could come from?

NOTE: Also, the fluid I drained was more of a brownish color. The leak I'm seing at the bottom of the seal between the Ally and the TC seem to more reddish like heathty DIII. I remember reading somewhere that this link between the two should be dry. I so; the leak could be comming from some other seal on the output shat of the ally? Any other sugestion?

I drained the TC this morning. Since it was leaking, only half a cup of DIII came out. I didn't see any metal shavings BUT something came out of the drain... It looked like molted resin or a blotch of glue. Any ideas where that could come from?

If the truck a fixed yoke or a slip yoke on the t case? I thought they were slip yoke and if so you can not drive it without the rear shaft in or you will loose fluid.

Joey D: The truck ran fine for 30 miles and just 1 mile away from home it began to slip somehow.

Here's a picture of the leak and one of the unknown resin blotch I got when I drained the DIII.

i would think from the bouncing the seal between the tc and trans broke or maybe the 2 are loose and need to be tightened i would check that and the silcone you found is probly from when it was put together if i understood you when you said it was like glue again just my 2 cents

If sounds like you ran the case dry and if the seal between the trans and the t case was bad it will also be low on fluid.
Did you have to unbolt the shaft from the t case or did it slide out? If it slides out it's a slip joint and should never be driven like that or the case may be toast. If so at this point you have nothing to lose so fill it all back up and replace the shaft and see how it drives. Try 4 wheel and 2 wheel to check it all out.

Just a note I seen on the sun coast web sight about the housing between the trans and trans case cracking due to the pendelum efect on the trans case they offer a bracket so must be pretty common. just a note to check out

Found a badly damaged U-Joint this afternoon on the front driveshaft (as suggested by Quicksilver) "Maybe" that was the source of my skipping/jerking. Will add that to the damage list... Can't quite remove the front shaft yet, I seem to want to come out but the rubber boot is holding it back. Will search the forum to find the correct method. My experience with broken damaged U-Joint is that I will hear noise and feel vibrations but a sudden skip/jerk seems more unlikely. Anyways, I have to replace it.

My TC was leaking a few month ago because of the pin-hole caused by the "missing clip effect", I patched the hole for the time being. I was told that other holes would appear but I would guess that it would be in the same general area as the first hole. I checked the TC very often to catch a new leak early. The seal leak I'm having is new and could only be a result of the violent bouncing. Now, my question is wether this joint between the tranny and TC is suposed to be dry, I mean could the Ally DIII be leaking there?

Found a badly damaged U-Joint this afternoon on the front driveshaft (as suggested by Quicksilver) "Maybe" that was the source of my skipping/jerking.

we can only hope thats the worst of the damage!!

You just need to pry behind the little metal clip deal that holds the rubber boot on. It fits really tight to seal. Just carefully pry it away from the transfer case and then it slides out...

Yup, got it... thanks.

The ujoint seems a little different. Are there "pins" holding them in place?

Stock ujoints are held in with plastic injected into those little holes on each yoke, easy way to get it out is heat the yoke by the cap for a second, it will squirt out the holes...

Now for the final result...

1- Broken U-Joint in front driveshaft
1- Broken U-Joint in the rear driveshaft
1- Broken in two rear Driveshaft
1- Slightly broken rear yoke
1- Sheared fuel tank protector metal sheet

1- Broken thingy in the transfert case (dont know the name yet but see picture) wich is also the source of the resin I found while draining the oil.
1- Broken output seal while craking the TC open
1- Destroyed seal between the tranny and the TC


And the unrelated but necessary...

1- Broken pump clip
1- Slithly buffed by the pump rear case because of broken clip

Will follow up on that transfer case defect in this thread:

http://www.dieselplace.com/forum/showthread.php?t=37492

The photo of the broken shaft is in that thread:

http://www.dieselplace.com/forum/showthread.php?t=44002

Now for the final result...

1- Broken U-Joint in front driveshaft
1- Broken U-Joint in the rear driveshaft
1- Broken in two rear Driveshaft
1- Slightly broken rear yoke
1- Sheared fuel tank protector metal sheet



I would replace the remaining u-joints as well. There have been several trucks in our club that pop a u-joint, then only replace that one and the next pull the other goes. Cheap insurance. The best we have found for pulling are Spicer non-greasables. FWIW.

Just a note I seen on the sun coast web sight about the housing between the trans and trans case cracking due to the pendelum efect on the trans case they offer a bracket so must be pretty common. just a note to check out

that was my guess, if you put a 4 wheel drive under extreme pressure, especially with a mated transfer case, sometimes the housing can crack causing it to leak

Just finished re-assembling and re-installing the transfer case. Truck runs fine in FWD. I've put a cap on the rear output to keep the fluid inside. I have 250km (it's on my way to my destination anyways) to go tommorow morning to a 8h00 appointement to rebuild my driveshaft for 400$CAN. It's a rebuilding shop, so you give it to them uninstalled and they give it back uninstalled. When I get it back 2 hours later, I install it in the parking lot.

For the transfer case parts, I realise that we get screwed alot with parts...

I called the GM dealer.

I needed 3 parts...

12473219 Fork... GM garage price: 122.80 $CAN
12474947 Front output seal...GM garage price: 100.60$CAN
12470559 Pump retainer clip...GM garage price: 10.12$CAN

Total: 233.52

I went to a transfert case/differential rebuilding shop same 3 parts from New Process:

Fork... price: 75.00 $CAN
Seal kitl... price: 50.00 $CAN
Pump retainer clip... price: made it myself 0.00$CAN

Total: 125.00$

So it seams that as it is the case with Allisson parts, GM is taking almost a 100% profit on the parts before distributing them to us. I must also point out that the Front Output seal that was 100.60$CAN was just one seal compared to the whole Seal Kit (except the rear output) wich was 50$CAN. If purchased separatly from GM, the whole kit would cost nearly 250$CAN. That's simply outragous...

Thanks for listening to the whole thread, hopefully, one of these day, the info and photos will be helpfull to someone.

i was pulling this year and started bouncing too, i twisted my drive shaft right in 2. (metal one) had another metal one made up. i caped off my output shaft and drove home maybe 20mi or so. no problems. then drove another 30mi round trip to get the new on made up, never had a problem, but!!!! i do have that suncoast bracket!

Rear driveshaft or not, the transfer case is not supported pass the tranny bracket on the cross member. The bracket does offer additional support but its absence does render the transfer case more vulnerable in normal conditions.

i have been saying that truck pulling isnt hard on your trucks, we just do it to find the next weakest link!

The slipping you are talking about is syptomatic of broken snap rings on the drive shaft of the Xfer case. Is there a banging or a popping sound to go with it?