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TR2/3/3A TR3 REAR TRANS SEAL

Alvin

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My trans (Std 4 speed - no OD) on my 59' TR3 is leaking out of the rear of the trans. I "assume" it needs a new rear seal. In looking it over it appears that there is not enough room to replace it from the bottom. Removing the tunnel and replacing it from the top would be quite a problem too because I made sure that the tunnel would not leak when I had my engine out last year. A combo of caulking and fiberglass made sure of that. Thus, removing the tunnel would be quite difficult. Is it possible to change the seal from the bottom or do I have to pull the trans, or is there another mechanical option? What about the trans seal junk they sell? Thanking you in advance for your valued input ........AL
 
Al --
The trans tunnel is meant to be removable for just this sort of service. I don't know if you can do the seal job from underneath, but it would be <span style="font-style: italic">much</span> more difficult than it would be from the top, if possible at all. Many years ago, before I knew how "easy" it is to remove the tunnel, I did a u-joint job from underneath. The front u-joint, while possible to get on-and-off, was REAL tight work.

My best advice would be to redo your tunnel sealing methods, so that it's not such a problem to get it off -- while you re-seal your tranny from the top.

Actually, I don't even know if you can do this job with the tranny in the car. There may not be room, even from the top, to get the access you need to R&R the flange and the seal. And, if that's the case, the tunnel has to come out anyway, to get the tranny in and out.
 
FWIW, a little heat will generally make both caulking and fiberglass let go, without harming the tunnel.
 
Thanks for your input. I guess the big question is: Can I replace the rear seal with the trans in or do I have to take the trans out. Either way I would have to remove the tunnel (I assume the trans must come out through the top). I took another look underneath and it looks like one of those don't do unless you have to jobs. It looks pretty ugly. I pulled the engine before and it was not fun. I might be forced to pour a bunch of sealer in the trans, which I really don't want to do, but it might give me relief till I have to pull the engine + trans again.
 
You can leave the engine in and just pull the transmission through the interior (again after getting the tunnel off).

Scott
 
On my TR4, I was able to jack up the rear of the transmission about 2" to replace the rear transmission mount. That same amount of movement may allow you to get a puller on that rear flange while everything is still in the car. So there is still hope that you can change out the seal without getting into too heavy lifting. But yes, that tunnel needs to come off.
 
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