Transmission leak

[DerangedMadman]

I have only had my M1008 for a few months. When I first got it it had a crack in the transmission line right at the brace were the lines cross over on the bottom. I ended up putting in a double sided compression fitting and it has worked great.

Since that time I have put about 2000 miles on the truck with absolutely no problems.

Last week I towed a 75 Camaro on a car dolly about 150 miles. When I arrived home there was transmission fluid leaking from somewhere. It was dark and late so the next day I went out to check it out and seen where fluid was sprayed all over the undercarriage and about halfway back on the bottom of the transmission pan.

I still could not pinpoint the leak. I went out of town for a week and finally was able to look at it today. I ended up having to put 2 quarts of tranny fluid in it.

Now the question. I drove it for about a mile after adding the transmission fluid, parked it in the driveway and cycled through the gears a few times. Shut it off and let it sit and there are no signs of a leak anywhere. When towing could the transmission of run hotter than normal when towing causing it to possibly build more pressure than it normally operates at?

Just seems from past experiences with other transmissions they either leak or don't leak so this one has me confused.

I will take it on a good drive tomorrow and let it get up to temp but any suggestions will help.

Thanks,

 

[acmunro]

I had a M1008 that seemed to leak worse when towing or trip driving than putting around town. It turned out to be
a cracked Transfer case adapter. I don't know if it was higher temps/ more fluid moving/ slight vibration that caused
it to leak more. I do know a new adapter fixed its problem. Good Luck.

 

[pigfoot63]

Don't know if this is your problem, but also check the fluid level in your transfer case. I f you remove the fill plug
and see trans fluid comming out you may have a bad front seal inyour transfer case. This seal is double lipped.
It seals the transfer from the transmission, sometimes it fails and the transmission dumps oil inthe transfer.

 

[DerangedMadman]

I will check both suggestions. It's just weird that it could leak our 2 whole quarts and now it is not leaking at all.

 

[wkbrdngsnw]

Sometime when autos are over full or get really hot the fluid reaches the vent and will leak down the passenger side from up by the bell housing area.

 

[DerangedMadman]

Thank you wkbrdngsnw but I wish it was that easy. The fluid level was good.

Ok, I hooked my 18 ft fish/ski boat to it today and drove it roughly 30 miles and the leak started again. I snapped a few pictures and I have the general area located.

The transmission itself is totally dry from the back of the pan forward. It seems like the fluid is coming out (definately on the drivers side) near the transfer case adapter.

I pulled the fill port from the transfer case and there was no transmission fluid in it so it seems like the front seal of the transfer case is doing its job.

This leaves the possibility of a cracked transfer case adapter.

Any suggestions for a gasket kit for this?

I am hoping that it is just the Gasket is blown out on the adapter. I am going to try to take it off this weekend and get a better look at it.

Thanks for the help!

 

[acmunro]

Takes 1 gasket and 1 o-ring. I get them from the Chevrolet dealer. I would like to find another source.

 

[acmunro]

I went out to the garage and still had the parts bags with some spares for sealing the adapter.

Gasket GM part number is 15642510

Rubber seal GM part number is 8623216

 

[DerangedMadman]

Thank you very much.

 

[DerangedMadman]

This turned out to be a cracked transfer case adapter as well. There is a fine crack in it almost 180 degrees across the top half of the adapter.

Doe anyone have one of these they want to sell?

 

[dstang97]

If you can't find one let me know. I know my friend did have one. He wanted $ 100 for both adapter and transfercase. Pm me if interested.

 

[hovenga67]

I have a spare on my other truck let me know.
Brent

 

[DerangedMadman]

I appreciate both you offers but I think it's a little to far for me to come and get.

I found one here locally and the guy wants $75.00 for it. Seems kind of high to me but I am kind of in a rush to get it back together. I need to use it next week to pull my boat to the Ohio River for vacation.

Here are a couple pics of the crack. It is hard to believe it cracked like that. All the bolts were tight and even had locktite on them. Fluids were good in both the tranny and transfer case when it blew.

 

[hovenga67]

Wow thats pretty bad. I could ship it if you end up needing it.
Brent

 

[acmunro]

adapter

I appreciate both you offers but I think it's a little to far for me to come and get.

I found one here locally and the guy wants $75.00 for it. Seems kind of high to me but I am kind of in a rush to get it back together. I need to use it next week to pull my boat to the Ohio River for vacation.

Here are a couple pics of the crack. It is hard to believe it cracked like that. All the bolts were tight and even had locktite on them. Fluids were good in both the tranny and transfer case when it blew.

I recently picked up a truck that had a broken adapter it was easy to tell. When I removed to change it it was in two pieces.

Does your driveshaft have any dings or bends in it ? If it does I would replace it. I think my first one cracked due to the vibration of a dinged up shaft. Is your crossmember bent ? Would be good to replace those items if necessary to prevent the new one from getting damaged. Good Luck

 

[DerangedMadman]

I recently picked up a truck that had a broken adapter it was easy to tell. When I removed to change it it was in two pieces.

Does your driveshaft have any dings or bends in it ? If it does I would replace it. I think my first one cracked due to the vibration of a dinged up shaft. Is your crossmember bent ? Would be good to replace those items if necessary to prevent the new one from getting damaged. Good Luck

None that I can tell. The cross member looks good. It does not look like it is bent at all and all the bolts in it are tight. I think I will take the driver shaft into a shop and have it checked. Maybe it is not balanced. Thanks.

 

[DerangedMadman]

The guy sent me on a goose chase, 3 1/2 hours round trip for the short one so I am still in need. I sent you PMs dstand97 and hovenga67. Thanks.

I talked to a guy at a transmission shop and he says this is normally caused by a u-joint. Looks like I might as well replace them all while I have it apart.

I am still in need of one if anyone has a spare.

 

[DerangedMadman]

UGH!!! Still no luck. If anyone has one available I am willing to take a road trip this weekend. Time is running out.

 

[dstang97]

I called my friend but he did not call me back. The short adapter will work you just need the matching cross member. as long as it a high mount. Th350/700r4/400.