• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!

    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
  • When posting a classified ad, you MUST select a prefix from the drop-down next to the subject line. If you don't you will get an error and your ad will not be posted!
Tips
Tips

TR2/3/3A tr3 tranys oil

sp53

Yoda
Country flag
Offline
I have been using 30weight oil in my tr3 trans for a long time, but I keep hearing that some new products on the market might be better. In addition to that has anyone ever used some of that miracle in a can to stop a tail shaft seal leak? But it might not be that important because it has been my understanding that tr3 tranys are not very oil tight anyway. I mean it looks to me like the shifting rods are going to let some oil escape over time. Moreover, what is the recommended mileage to change the transmission oil/fluid? I have a book somewhere, but I just moved.
Steve
 
It is possible to get them sealed up ... there are supposed to be seals on the shifter rods, but I've heard that the ones sold for the purpose do not fit properly. I bought some "quad seal" O-rings plus teflon backing rings from MMC that seemed to work almost too well ... the shaft needs a little bit of oil or it will rust!
https://www.mcmaster.com/#o-rings/=8xa1fr

Never tried any of the "seal sweller" stuff in a TR, but it's never helped any of my other cars, so I'm dubious that it would help here either. Just replace the seal, and add a Speedi-sleeve if the surface of the flange is at all dubious.

Factory recommendation for TR3 was to drain & refill every 12,000 miles.

I'm using Redline MT-90 in my TR3/4/6 gearbox and I really like it. YMMV and all that.
 
Thanks Randall for your input, and I am curious did you replace the seal with the transmission in the car?
Steve
 
sp53 said:
I am curious did you replace the seal with the transmission in the car?
Once, many years ago. Been so long I don't recall the details, except that I was scared to apply as much force as it took to lever the old seal out. But I did the differential input seal just a couple of weeks ago, and it's pretty much the same thing.

Just remove the flange and use a big screwdriver to pry the old seal out. On the diff, I started with a "seal puller" from HF, but it broke almost instantly. The big screwdriver (you know, the 2 foot monster that never gets used for actually turning screws) popped it right out, though.

IMO, it's worth building a simple tool, which can be seen in action here. This is just a metal bar from Home Depot, drilled so it can be bolted to the flange and used for leverage. You can see where I didn't get the holes positioned just right and had to grind away a bit to have room for the socket, but of course you won't make that mistake
grin.gif


At the gearbox, you'll probably have to remove the driveshaft to get room to work, but at the diff I was able to just prop it up out of the way with a jackstand.

Polish up the sealing surface of the flange with a piece of fine abrasive cloth. If you can't remove the mark where the seal rode, it's probably time for a Speedi-sleeve. Or you can try not driving the seal in all the way, so it rides on a different place.

Don't forget to coat both the lips of the seal, and the surface of the flange liberally with grease or assembly lube before putting it back together.
 
I drilled a couple small holes in my diff seal and screwed in a couple sheet metal screws. Then, that cheap HF slide hammer pulled the diff seal out with little effort. Mine needed the SpeediSleeve. Moss was a good source for that.

Pat
 
PatGalvin said:
I drilled a couple small holes in my diff seal and screwed in a couple sheet metal screws. Then, that cheap HF slide hammer pulled the diff seal out with little effort. Mine needed the SpeediSleeve. Moss was a good source for that.

Pat
I like that idea. :banana:
 
I dunno, creating metal dust inside something that you don't plan to disassemble and clean seems like a last resort, to me. But maybe I'm just paranoid.

DSCF0044_reduce.jpg
 
Randall I have not done this, but it seems to me that I could undo the tail shaft from the body of the transmission and remove just the tail then put the new seal in on the bench. It looks like I would only have to drop the speedo gear and unbolt the tail form the body. I am not sure of the clearances there would be or if it is possible, but it looks doable. What do you think?
Steve
 
Maybe self tapping screws then ? Seems like you'd likely just have a burr hanging on to the back of the hole ?
 
sp53 said:
Randall I have not done this, but it seems to me that I could undo the tail shaft from the body of the transmission and remove just the tail then put the new seal in on the bench. It looks like I would only have to drop the speedo gear and unbolt the tail form the body. I am not sure of the clearances there would be or if it is possible, but it looks doable. What do you think?
Seems very unlikely to me. Don't forget, the housing has to come off of the mainshaft, which runs all the way through the housing. I don't think the body gives enough clearance to move it that far back with the gearbox in the car. The housing also doesn't usually want to come off, takes either a puller or some rather determined pounding to get the tail bearing to slide off of the mainshaft. And you wouldn't want to pound on it, since you're not replacing the bearings that could easily get damaged in the process.

Besides, it's an awful lot of work for just a seal.

If you really don't want to do it in place, I would look into undoing the rear mount and jacking up the gearbox until you can work above the tunnel. But watch that you don't run the fan into the radiator. You could also try removing the rear crossmember and lowering it, but the same caveat applies plus don't let the back of the engine hit the throttle linkage on the firewall.

But either way, you've done 80% of the work of just removing the gearbox. Might as well pull it the rest of the way and replace the front seal as well. It's gone more turns than the output anyway.

Or is that the shipwright's disease talking ?
:devilgrin:
 
poolboy said:
Maybe self tapping screws then ? Seems like you'd likely just have a burr hanging on to the back of the hole ?
Could work, if you can drive the screws in to create the hole (or start with a punch).

But still sounds like a lot of work compared to just tapping a screwdriver in and prying the seal out. It took me several tries to get a good enough bite on the pinion seal, but I still don't think it was 5 minutes from the time I got the flange off until the seal hit the ground.

Biggest stumbling block was that the replacement seal didn't fit ... now I know why I'd marked a big "?" on the box
grin.gif
 
Back
Top