M1008 Th400 broken case issue

[2deuce]

I accidentally backed over a TH350 with my deuce and it broke the back of the tranny just like a bad driveshaft would. When your tranny is on the ground try to keep your deuce away from it. Sorry I'm not much help.

 

[WARWAG]

you must have taken your truck to a pretty shady transmission shop - for him to have replaced the adapter and left a cracked transmission in place ....

My guess is GL picked up the truck with a forklift and broke the adapter/transmission and probably bent the driveshaft --which at highway speed....caused unbalanced harmonics to build to the point to where you experienced the highway failure of the new transmission.

if you cant do it - have a driveline specialist look at this truck and tell you what it needs---I wouldnt suggest going back to the original trans shop.

Ditto.

Seen them bring trucks to a customer on a huge fork lift and drop it off after running down the dirt track and truck bouncing up and down with all the weight on driveshaft and transfercase. Yah bad deal. I bet your rear drive shaft is bent. Pull it and sight down it. Take it to a drive line shop. Rebuild the trans.

 

[ODdave]

dose your front drive shaft colapse and extend easily? i have seen them seized and when the front suspention compresses it snaps the trans. also make shure the shaft is the correct length.

 

[pmramsey]

Place any and all drive shafts on a perfectly flat surface and roll them. No matter how straight they may appear, many are bent. Anyone that purchases a CUCV with a bent shaft from GL should expect to at least replace the transmission case along with the shaft especially if you listen to the guy that said all you had to do was shift the transfer case and the truck into neutral before towing it home; you are eating away at everything. Plus, many of the cases crack when the shaft gets bent.

 

[IdahoPlowboy]

Sorry guys, its torrential rain here for me to get underneath and take a pic of the braces-support rods. There are 3 of them. 2 shorter ones go from the frame where the motor mounts are to the bottom of the bellhousing. The long thicker bar goes from the block by where the starter mounts to, then goes all the way to the right side of the transfer case. Its mounted with two huge bolts, if you look you'll see the holes for these bolts.

I was told that withought these braces, you'll brake the tranny. So I measured them off, went to a wrecker that only does Chevy trucks, he had quite a few in different lenghts! The longer one I found. The two shorter ones I had to cut and reweld to get the correct length. Cant remember where I sourced out the bolts, I think I bought them new. I did have to borrow a tap to chase the threads so that they threaded in easily.

When it clears up here, I can take pics and post them if you like.

I would like to see your pics if you get a chance. I am trying to put these braces on my truck and have no idea what they look like.

 

[Hasdrubal]

Here's the brace pics ;

 

[killer_kricket]

Definitely don't have those on my 1009. I have been pulling the starter quite a bit recently and there are no braces.

As for the cracked trans, the same happened to me with two different housings. The solution was simple: weld back together and pay the driveline shop for a new driveshaft. (GL bent the old one)

 

[IdahoPlowboy]

Great pics, they are very helpful. Thank you.

 

[allenhillview]

Sorry guys, its torrential rain here for me to get underneath and take a pic of the braces-support rods. There are 3 of them. 2 shorter ones go from the frame where the motor mounts are to the bottom of the bellhousing. The long thicker bar goes from the block by where the starter mounts to, then goes all the way to the right side of the transfer case. Its mounted with two huge bolts, if you look you'll see the holes for these bolts.

I was told that withought these braces, you'll brake the tranny. So I measured them off, went to a wrecker that only does Chevy trucks, he had quite a few in different lenghts! The longer one I found. The two shorter ones I had to cut and reweld to get the correct length. Cant remember where I sourced out the bolts, I think I bought them new. I did have to borrow a tap to chase the threads so that they threaded in easily.

When it clears up here, I can take pics and post them if you like.

Great pics, Can you tell me more about those braces? I'm not sure of the plate near motor mounts, is it there already? my 1008? Where can I find measurements? We can make if I have right dimensions, tow all the time need these bad. Its crazy they didn't put them in,(gov.) Anything you can do would be grateful.

 

[Cucvnut]

I have one.

 

[allenhillview]

The brace and the plate or is the plate there? I got under there earlier and still not sure of the plate I'd like to have which ever you have, PM me.

 

[lincolntwilliams]

I'm guessing a bent rear drive shaft could break 2 transfer case adapters right? My drive shaft has a good dent in it.

 

[2deuce]

Those braces are interesting. I've had quite a few CUCV's and parted out a few civilian suburbans and never ran across those braces.