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Leaking transmission

G

garner67

Active Member
My transmission is leaking out of the tail shaft seal. I know my transmission builder installed a new seal. Strangely enough, it looks like it's coming from inside diameter of the slip yoke, not along the outside diameter where the seal rides along the slip yoke.

Tech details: T5 with G-Force gear set. New driveshaft professionally build with new slip yoke, and it doesn't "feel" like there is any slop between the slip yoke and the trans output shaft.

Has anyone had this problem? Is there some sort of sealant I could use along the ID of the slip yoke to stop the leakage? Any ideas are welcome.

Also, I'll be contacting my trans builder Tuesday, to get his opinion too.
 
"garner67" said:
My transmission is leaking out of the tail shaft seal. I know my transmission builder installed a new seal. Strangely enough, it looks like it's coming from inside diameter of the slip yoke, not along the outside diameter where the seal rides along the slip yoke.
Click to expand...

Never heard of that ! leaking from inside of the slip yoke.
Has your slip yoke a crack?
 
"B67FSTB" said:
Never heard of that ! leaking from inside of the slip yoke.
Has your slip yoke a crack?
Click to expand...

I kinda doubt it. It's a brand new slip yoke. The driveshaft builder said the driveline should be able to handle over 800 hp.

I'll be taking it apart later this week, and I'll definitely inspect the slip yoke very closely.
 
Michael,
When the driveshaft is in place, how much travel do you have when you slide the driveshaft forward as if you were removing it? Did you do the old school of determining driveshaft length by inserting the yoke all the way into the tranny and then pull it back by 1" to determine it's new location or length of shaft needed?
 
"cmayna" said:
Michael,
When the driveshaft is in place, how much travel do you have when you slide the driveshaft forward as if you were removing it? Did you do the old school of determining driveshaft length by inserting the yoke all the way into the tranny and then pull it back by 1" to determine it's new location or length of shaft needed?
Click to expand...

I'm not exactly sure how much travel there is to move the driveshaft forward. I'll check that when I remove it.

To determine the length I used the driveshaft builder's method of measuring the total driveline length. I measured from the tail shaft housing end to the center of the pinion yoke.

Here's the actual form I completed when I ordered my driveshaft.

M1-1%201piece%20New%20Slip%20Yoke%20w%20Reg%20Pinion2009.JPG


Still waiting to hear back from Bruce @ ModernDriveline.
 
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Unless you have some weird DS yoke that I'm not familiar with, I don't see how it's possible for it to be leaking on the inside of the yoke....

My bet is it's the tailshaft seal and the fluid is running backwards wetting the yoke.
 
Does anyone know if you can replace the tail shaft seal without removing the entire tailshaft from the trans case?

If it is the tail shaft seal, I'd like to avoid pulling the entire trans just to replace the tail shaft seal.
 
Just so that we're perfectly clear..... the tailshaft seal that is at the very rearward end of the transmission..... that seals the OD of the driveshaft's yoke..... yes, it's a simple pressed-in seal. Similar to an axle tube seal or the timing cover's seal around the crankshaft snout. Pop the old one out with a screwdriver and gently "tap" the new one in with either a large socket or a piece of pipe that has the same diameter as the seal's metal flange.

The new seal's should be available locally at any auto parts store.
 
"daveSanborn" said:
Just so that we're perfectly clear..... the tailshaft seal that is at the very rearward end of the transmission..... that seals the OD of the driveshaft's yoke..... yes, it's a simple pressed-in seal. Similar to an axle tube seal or the timing cover's seal around the crankshaft snout. Pop the old one out with a screwdriver and gently "tap" the new one in with either a large socket or a piece of pipe that has the same diameter as the seal's metal flange.

The new seal's should be available locally at any auto parts store.
Click to expand...

Coolio... I'll go pick up a new seal today. I was worried that I'd have to pull the trans if the seal was pressed into the tail shaft. Sounds like I can r&r the seal while it's in the car.
 
Is that not a dust cap

I think there is an inner seal.

picC4.jpg
 
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At worse case, you can always the rear tail housing, replace the seal and reinstall the housing, without removing the tranny.
 
Got the old seal out tonight. I mangled it during removal. Now, I need to find something to drive the new seal into the tail shaft. The driver has to have a 2.4" ID.

I'll first look for a piece of pipe at the hardware store with the right ID; if that doesn't work, I'll buy a socket that should do the trick.
 
"garner67" said:
Got the old seal out tonight. I mangled it during removal. Now, I need to find something to drive the new seal into the tail shaft. The driver has to have a 2.4" ID.

I'll first look for a piece of pipe at the hardware store with the right ID; if that doesn't work, I'll buy a socket that should do the trick.
Click to expand...

Ummm ... why wouldn't you just buy a seal driver kit from Harbor Freight? You'll use it over and over and it's less than $30.
 
"johnpro" said:
Ummm ... why wouldn't you just buy a seal driver kit from Harbor Freight? You'll use it over and over and it's less than $30.
Click to expand...

Sounds like a much better plan than using some "improvised" solution.
 
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