TR2/3/3A Correct oil level for differential?

[karls59tr]

On most cars if you put put a finger in the diff fill hole and the oil level is just below the fill hole your good to go. Is this correct for the TR3 or is it possible to overfill the diff? I just topped it up with the intent to monitor the seal leak. If it's not too bad I would like to postpone changing out the seal until Fall. Don't want to overfill and make the situation worse.
Karl

 

[TR3driver]

I believe bottom of the threads is enough; however top of the hole (where it runs out) is fine too. The level is not all that critical.
But higher than that (say having it tilted when filling level full) might increase leaks a bit. Any leakage should be from the vent hole on the top, though, not the axle seals.

Leaking pinion seal is no big deal, but leaking axle seals are very apt to let oil into the brakes, which of course makes the brakes not work. I'd do axle seals sooner rather than later; as brakes are kind of important.

 

[Geo Hahn]

When I had an axle seal fail I did not notice until the (oil-soaked) shoe linings fell off. That got my attention.

Had to drive home from New Mexico with the rear brakes disabled - not really noticeable in casual driving.

Yes, some may raise the rear end quite a bit to get at the fill plug so the level needs to take that into consideration.

 

[karls59tr]

When I had an axle seal fail I did not notice until the (oil-soaked) shoe linings fell off. That got my attention.

Had to drive home from New Mexico with the rear brakes disabled - not really noticeable in casual driving.

Yes, some may raise the rear end quite a bit to get at the fill plug so the level needs to take that into consideration.

I had better double check the level as I had the back of the car on jack stands when I filled. Front brakes do 80% of the braking but I better address the situation soon.

 

[sp53]

So, Geo what technique did you use to separate out the rear brakes?

 

[Geo Hahn]

In a 'pinch' (pun intended) I carry a metal clamping plier the shut off the rear hose. I did this on the TR3 (seized cylinder, opened the bleeder to relieve) as I only needed to drive a few miles.

I also carry a plug made from an old metal line that works well and avoids squeezing the soft line:

I used the plug on the TR4 as I was a few hundred miles from home.