OD Seals : better left alone...or change and risk new leaks?

I believe I know the answer to my question, though posing it here is always helpful, to say the least.

I will be in OD-transition coming up - changing the OD that came with the recent 77 (Blue Label) I acquired to my 79 B. Took the 77 for a drive again last night to test out the re-calibrated Weber - and oh-well - might as well - take her up to 50 MPH down the country road behind my house - and flick the OD into "IN" in 4th gear and --- oh what a feeling...5th gear aplenty!

[color=#336633]I have asked this question and some say change, some say - absolutely NO, (the rear seals of the front/back of the gearbox). Unless they're leaking, don't bother, because you're likely to create more leaks based on a speck of dirt that gets on seal-surface, an incorrect fitting, or other issues that arise from changing seals, etc.[/color] And what about the side covers seal and the OD filter seal, (probably I suppose).

What say you?

Dan, I say go ahead and replace the seals. If you are careful, and reasonably skilled you won't mess up the job. These parts do wear out and deteriorate with age, so they do need replacement on an older car.

The side cover gasket to the tranny should last forever, so no need to replace it, unless you open up the cover.

The OD filter,and O rings are also an easy maintenance item, and I would do that...just be careful with the o-rings, cause there are some small parts that can be lost if you don't pay attention.

Also, change the OD oil!

Good luck.

Front and rear seals are not an easy project without partial disassembly of the transmission. You can pry or use a slide puller to get them out but installing the new ones will be a problem as the shafts will get in the way. If it ain't leaking and works fine I'd just put it in. The gasket /screen should be changed as well as the fluid. The o-rings that are easily accesable are probably the same age as the ones that aren't. You are very lucky to have got one you were able to test drive. Most of us buy these as a pig in a poke. Change the fluid, screen and enjoy.

The people who have the most problems are the ones who tinker with things that don't need tinkering. If it doesn't leak then what is the point of taking it apart and replacing the seals?

Okay - the 77 (with the OD) - doesn't have any evidence of leaking around the gearbox rear or front, (from under the car).

So no need change the seals. Dumb Question : :P When I remove the OD gearbox from the engine, what should I look for, (...oil) on the inside of the bellhousing? Or if there's leaks from the front/rear seals of the OD gearbox, what are the symptoms exactly - oozing oil around the seal, or what? Thanks.