87 K5 Transmission to Case Question

[stano]

We have a 87 K5 (or V10) with 350 engine, and 700 auto, 4WD,.. I noticed leak of transmission fluid. Went under the truck and saw a 1/16" gap between the trans tail and the piece that has the tail mount to the cross menber. I saw two bolts going to the front of the tuck (one was hard to see because of webing on the casting). That were loss.. I asummed there may be two more on the pass side also.

Is there a gasket between these two pieces? If so could it drop out or stay in place...I would like to just tighten these bolts backup for the winter and fix next spring as truck will only run to move it around for winter.

thank you stano

 

[munepit]

There is no gasket on the tail cone. There are 5 or 6 bolts though. Undo the bolts and take a rubber mallet to break it loose. Tap gently. Then just use RTV to seal it.

Scratch that. I was thinkin the transfer case. Sorry! There is a gasket connecting the tranny to the transfer case though.

 

[4X4HIGH]

There is no "gasket" but rather a large o-ring between the trans case and the t-case adapter. You have to pull the t-case in order to tighten those 4 bolts. It is possible that the threads in the trans case are stripped (common problem) and you might need to heli-coil them. The bolts should be a metric 10mm x 1.5 IIRC.

 

[munepit]

Boy was I wrong! Shocker!

 

[stano]

thank you Scott and Jeff for your help.. I was able to tighten the four bolts with a open-box wrench.. I got them fairly tight. I could put a little hand presure on each bolt.; So we are lucky they are not stripped.. I also took down the shift linage on the pass side to help.. So i think i got them tight enough for this winter and maybe a couple of trips into town. But next spring I will pull the cross member and put some new bolts in there and hopefully get them nice and tight without stripping them..

thank you guys stano

 

[ChevyBoy2010]

thank you Scott and Jeff for your help.. I was able to tighten the four bolts with a open-box wrench.. I got them fairly tight. I could put a little hand presure on each bolt.; So we are lucky they are not stripped.. I also took down the shift linage on the pass side to help.. So i think i got them tight enough for this winter and maybe a couple of trips into town. But next spring I will pull the cross member and put some new bolts in there and hopefully get them nice and tight without stripping them..

thank you guys stano

Use some thread locker. Itll save your life, literally.

 

[stano]

good idea thanks

 

[wasted wages]

I can't stress this point enough on auto trans cases.....

pull the adapter plate off the transmission....

measure the length of the bolts and type of threads.

spray all the crud out of the threaded holes in the trans case with brake cleaner...

INSPECT the bolt holes and the flange area on the case for any cracks and stripped threads. helicoil as needed.

run a tap into the case threads to be sure they are clean..

wash the threads out a second time and blow dry with shop air.

install grade 8 or better studs of the proper size and length into the trans case with red loctite.

reinstall the adapter using grade 8 washers and lock washers and nylock nuts.

TORQUE TO SPEC !! and then check it again.....and then once more just for good measure...


I install this on every transmission I work on when I pull an adapter plate...
T-350's are the worst... 4 - 3/8 bolts is all that GM uses to mount the adapter. 1 loose bolt or stripped thread and it's almost certain death....

I've seen transfer cases fall off T-350's when the bolts let go...

T-400's use 6 bolts and are a little stronger, although I've had a few cases crack at the output flange also...

 

[ChevyBoy2010]

I can't stress this point enough on auto trans cases.....

pull the adapter plate off the transmission....

measure the length of the bolts and type of threads.

spray all the crud out of the threaded holes in the trans case with brake cleaner...

INSPECT the bolt holes and the flange area on the case for any cracks and stripped threads. helicoil as needed.

run a tap into the case threads to be sure they are clean..

wash the threads out a second time and blow dry with shop air.

install grade 8 or better studs of the proper size and length into the trans case with red loctite.

reinstall the adapter using grade 8 washers and lock washers and nylock nuts.

TORQUE TO SPEC !! and then check it again.....and then once more just for good measure...


I install this on every transmission I work on when I pull an adapter plate...
T-350's are the worst... 4 - 3/8 bolts is all that GM uses to mount the adapter. 1 loose bolt or stripped thread and it's almost certain death....

I've seen transfer cases fall off T-350's when the bolts let go...

T-400's use 6 bolts and are a little stronger, although I've had a few cases crack at the output flange also...

Good advice!

 

[stano]

Well mine were loose so something is happening there.. thanks guys

stano