TR2/3/3A tr6 Type A OD tranny service

[GTP1960]

Hello,

i could use some guidance on changing my A type OD tranny oil.

questions:

is the large brass plug/cover at the base of the OD the drain port for the OD?
(Mine has a small leak I think , any suggestions on sealing?)

what is the best way to fill the oil?
the small port on the side of the hump is of no value. To small and out of alignment.
I'm thinking a flex neck oil pump can, under the car, but the manual says 2L capacity.

last question: the OD service manual says sae 30w mineral oil in summer, But no one has mentioned that in past forum post ( last couple years anyway).

so I'm leaning toward valvoline syn. 75-90 gear oil.


Thanks and and best regards,

Guy

 

[TR3driver]

Big brass plug is the drain. Fill port is on side of gearbox (they share oil).

Very early, Triumph did recommend motor oil, either 30 in winter or 50 in summer. But they changed around 1960 to recommending GL4. Supposedly, that was because the GL4 gave better protection to the countershaft bearings in the gearbox.

Personally, I like Redline MT90. OD operation is about the same, bit the synchros work noticeably better with it.

Sta-Lube has a manual oil pump that works well for filling the gearbox/OD. Should be under $10 at FLAPS.

 

[TR3driver]

Often, leaks from other places look like they come from the plug.
Make sure the gasket is in good shape, or just replace it. I had one crack and it was hard to see until I thought to try gently pulling on it.

Also check the sealing surface on the plug. It's easy to distort, especially if someone has tried to remove by just one ear. I think Moss sells a tool (but I made my own from a big socket).

 

[CJD]

The gasket is a bit of a catch 22. If you tighten it enough to stop leakage, then you will have trouble removing the plug next time. I went to Ace hardware and found an o-ring that would fit around the big plug. That stopped the leakage and allowed me to just snug the plug.

 

[GTP1960]

Thanks guys.
i ordered the MT90 & a gallon bottle pump.

o-ring sounds like the way to go, for me.

 

[Geo Hahn]

Big brass plug is the drain. Fill port is on side of gearbox (they share oil)...

Maybe I don't need to but I always drain from both the big brass plug and the small plug on the bottom of the gearbox.

For filling I cut a hole in the tunnel - forward hole in this shot:

Easier in cardboard but doable in sheet metal.

When I fill I find after a short drive I can add a bit more - possibly it takes some time for the oil to even out between the gearbox and OD.

 

[CJD]

That's the way...also, love your radio mount, Geo. Got any more shots of that?

 

[GTP1960]

For filling I cut a hole in the tunnel - forward hole in this shot

Geo,

sp what is the large rectangle port for?
also, do you have a plug for that hole?
do you. Cover the tunnel with carpet?
thx

 

[GTP1960]

Man, my tranny was low on oil.
just pumped in about 20oz.
had it serviced a year ago.
but hadn't checked it myself.

drove it about 1000miles.
no big leak, though it does have a slow drip.
guess I'll start checking it monthly.

 

[Geo Hahn]

I believe the radio mount is 'as original' though they may have varied and are also seldom seen from that angle. The car has no heater so I get a couple of unused holes below the radio - OD indicator light and 'secret' kill switch.

The rectangular tunnel hole is for removing/replacing the OD solenoid, it is covered with a metal plate. I have never had to touch the solenoid or OD since installation so the added hole seems to have worked (as a good luck charm).

As for your low oil - since you had not previously checked it, it is possible some of that is due to it not being totally filled the last time. As I mentioned, I usually find that it seems full until things run a bit, after which I can add more.

 

[CJD]

I would imagine there is a significant difference whether you cycle the OD to vent all the oil out of the accumulator or not...and likewise, if you top it up with the accumulator empty, and then check after driving.