As the title says, my transmission is leaking transmission fluid (red) between the rear case of the transmission and the transfer case. I only ge a few drops but the whole area there is "wet". I looked at a lot of drawings I found in the internet but cannot identify where the allison transmission seals the output shaft that goes into the transfer case nor do I see if there is a proper sealing between the allison housing and the transfer case housing. Any ideas??
Allison 5sp: Leak between Allison and TC Case
- Thread starter emkay
- Start date
There is a gasket between the Alli and the transfer case. The gasket is not known for going bad unless the nuts holding the two units together got loose. You might also check for cracks in the Alli extension housing.
the gasket is in this kit, its the only one I could find but I didn't look very long.
http://www.merchant-automotive.com/transfer-case-pump-upgrade-kit.aspx
I imagine you can get that gasket separate though.
http://www.merchant-automotive.com/transfer-case-pump-upgrade-kit.aspx
I imagine you can get that gasket separate though.
Tony Burkhard
Allseason Diesel Per.
http://allseasondieselperformance.com/index.php?main_page=product_info&cPath=43&products_id=167 Here is the gasket. Did you ever have a bad u-joint?
The Allison does not seal the output shaft, the seal to stop oil migration between the Alli and the transfer case is on the front input shaft of the transfer case.
That will not cause an external leak. The T/C front seal is to keep the T/C fluid from leaking into the Alli.
@mike: the ally was upgraded 2 years ago including the transfer case brace from suncoast, the truck has approx. 5000 miles since then and 20000 at all. so I hope there are no cracks...???
@ all: thanks for the links. so reading the last post I assume the leak can only be at the seal between ally and tc case, right? the seal on the tc side does not have anything to do with red oil leaking out, right? (tc is filled with motor oil as mike recommends). so if I open the ally/tc connection, I have to drain the ally first, right?
@ all: thanks for the links. so reading the last post I assume the leak can only be at the seal between ally and tc case, right? the seal on the tc side does not have anything to do with red oil leaking out, right? (tc is filled with motor oil as mike recommends). so if I open the ally/tc connection, I have to drain the ally first, right?
Check the nuts that hold the two units together first. They could be loose. The gasket between them may be bad. You may have a crack in the Alli extesion housing. If you have a crack it will usualy be on top of the extension housing. Use a mittor and a flashlight to try and spot it. You do not have a transfer case leak.
You do not have to drain the Alli if you pull the transfercase as all acumalated fluid in the extension housing will drain into the trans pan by way of the inner drain hole inside.
You do not have to drain the Alli if you pull the transfercase as all acumalated fluid in the extension housing will drain into the trans pan by way of the inner drain hole inside.
My puller was leaking in the same place after putting motor and tranny in. Put black rtv sealant there instead of the gasket. Hasnt leaked a drop since.
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Sorry to derail and hijack but Mike I just recently lost one of the nuts that connects it all together. Do you happen to know the thread or have any extras you can sell.
Mine's been leaking since I had my trans done years ago. Not even bad enough to worry about really except having to lay some cardboard down when I pull in the shop. I'll clean it and it'll eventually coat the back of the pan and drip from there.
seems my leak is really between ally and tc... not a good place for an easy fix I am afraid? to get there, I think the rear transmission mount has to be fully removed, the driveline and then the tc, right? what do you guys think is the way to go regarding the gasket, take a new one or just use rv seal?
as of the tc case pump rub issue, I already installed the riversidegear plate... good or what
as of the tc case pump rub issue, I already installed the riversidegear plate... good or what
Jesus, take another nut off, got to that place that sells nuts, and buy another one. . . . . .