T56 Magnum tail shaft seal leaking

LV_Ford_Fan

Member
Established Member
Joined
Dec 13, 2012
Messages
71
Location
Southern Nevada
Yikes, brand new transmission came with bad seal. Very small leak that I just noticed when under the car. No leak on the garage floor. Probably only 100 miles or less of driving on it. Sigh!
 

03' White Snake

Well-Known Member
Established Member
Joined
Feb 5, 2007
Messages
3,851
Location
Mass
Yep. More common than you think. Happened to my friends too. He replaced it with a Viper seal if I remember correctly. Has a spring on it, much better seal.

Watch the shifter too. The stock magnum shifters are junk, there is a seal on the bottom of the shifter that tears and leaks fluid. I went through 2 before replacing the shifter with a Tick unit.
 

LV_Ford_Fan

Member
Established Member
Joined
Dec 13, 2012
Messages
71
Location
Southern Nevada
I saw the problems posted about the stock shifter. I put in a Tick Shifter on day one. For seals I found the SKF 16725 and the TIMKEN 7300S. They both have the spring, metal housing, and the boot. Not sure if they are the correct ones.
 

amurray7777

Member
Established Member
Joined
Oct 27, 2021
Messages
49
Location
Florida
Yikes, brand new transmission came with bad seal. Very small leak that I just noticed when under the car. No leak on the garage floor. Probably only 100 miles or less of driving on it. Sigh!
I have the same problem. It’s brand new and got about 2500k on it and just started leaking yesterday. Wtf.
 

amurray7777

Member
Established Member
Joined
Oct 27, 2021
Messages
49
Location
Florida
IMG_2003.jpeg

I have the same problem. It’s brand new and got about 2500k on it and just started leaking yesterday. Wtf.
Any idea where this is coming from? Rear tail shaft seal?
 

03' White Snake

Well-Known Member
Established Member
Joined
Feb 5, 2007
Messages
3,851
Location
Mass
View attachment 1799833

Any idea where this is coming from? Rear tail shaft seal?
Looks like your mount is covered in fluid too. I’d look more toward the front. Stock shifter?? Could be the stupid seal on it. Pull the shift boot in the car, then the rubber seal around the shifter. If it’s wet it is the seal on the bottom of the shifter. Common problem.

Did you put in a real plug or did your magnum come with a plug in the secondary Speedo location? My came with a rubber push in plug, I swapped it for a billet aluminum plug with a screw to hold it in place. My buddies more recent magnum came with a real plug already installed.
 

amurray7777

Member
Established Member
Joined
Oct 27, 2021
Messages
49
Location
Florida
Looks like your mount is covered in fluid too. I’d look more toward the front. Stock shifter?? Could be the stupid seal on it. Pull the shift boot in the car, then the rubber seal around the shifter. If it’s wet it is the seal on the bottom of the shifter. Common problem.

Did you put in a real plug or did your magnum come with a plug in the secondary Speedo location? My came with a rubber push in plug, I swapped it for a billet aluminum plug with a screw to hold it in place. My buddies more recent magnum came with a real plug already installed.
 

amurray7777

Member
Established Member
Joined
Oct 27, 2021
Messages
49
Location
Florida
Yeah it’s the stick shifter that came with the trans. I’m not sure about the Speedo plug. My TKO son my Foxbody was leaking like crazy from there before I had it repaired. I guess I’ll have to pull the dust cover off and check the shifter itself. What do you there just reseal it? I’m so sick of this damn transmission.
 

amurray7777

Member
Established Member
Joined
Oct 27, 2021
Messages
49
Location
Florida
Looks like your mount is covered in fluid too. I’d look more toward the front. Stock shifter?? Could be the stupid seal on it. Pull the shift boot in the car, then the rubber seal around the shifter. If it’s wet it is the seal on the bottom of the shifter. Common problem.

Did you put in a real plug or did your magnum come with a plug in the secondary Speedo location? My came with a rubber push in plug, I swapped it for a billet aluminum plug with a screw to hold it in place. My buddies more recent magnum came with a real plug already installed.
Where else could it be leaking in the front?
 

03machstock

Member
Established Member
Joined
Nov 21, 2008
Messages
48
Location
Pennsylvania
Ahhh yes, the t56 magnum tail shaft leak, the bane of my existence. I could tell you all sorts of stories of my headaches, some actually pretty funny. I just put my 5th seal in, 4th different style. I haven’t driven it yet but I can update the post if it ends up sealing. How’s your trans doing OP? Stay sealed up?
 

03machstock

Member
Established Member
Joined
Nov 21, 2008
Messages
48
Location
Pennsylvania
Well my new seal leaks. I’m all ears if someone found one that doesn’t leak. I haven’t just been swapping seals, I also had the drain back passage machined in mine as it was an early unit that didn’t have it from the factory (I’ve had the trans since new for 9 years now but I’ve always had the drip at the tail shaft.) , and I put a new slip yoke in too.
 

MG0h3

Well-Known Member
Established Member
Joined
Jul 23, 2014
Messages
13,919
Location
El Paso, TX
Did you confirm it’s not coming from the shifter?

Call Hanlon Motorsports. Only people I use for T56 matters.


Sent from my iPhone using svtperformance.com
 

03machstock

Member
Established Member
Joined
Nov 21, 2008
Messages
48
Location
Pennsylvania
Did you confirm it’s not coming from the shifter?

Call Hanlon Motorsports. Only people I use for T56 matters.


Sent from my iPhone using svtperformance.com
Yea I actually have a hanlon short throw in it, it’s not leaking from there, you can see where it’s coming out of the tail shaft and flinging out everywhere. I just reached out to them as well, just asking around to see if anyone knew of anything else, thanks.
 

LV_Ford_Fan

Member
Established Member
Joined
Dec 13, 2012
Messages
71
Location
Southern Nevada
I have not seen any evidence of a leak on the garage floor, but I have not looked under the car lately. When I have a chance I will take a look and let you know.
 

ITSTOCK

Well-Known Member
Established Member
Joined
Sep 9, 2004
Messages
1,783
Location
wv
I had the leak on mine, sent back a handful of times. The problem from the beginning was a bad cast from the main to the tail section, the surfaces didn't mate flat and true. They kept sending it back saying all good, but still the same leak. Finally, they sent a new trans and all good after that.

The biggest problem was that I couldn't open it up and address myself because they stated that if I did, the warranty was void. Otherwise, it would have been a relatively easy fix.
 

Users who are viewing this thread



Top