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My od probs, kind of like Toms!

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TR4nut

TR4nut

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Thought I'd start a separate thread on the overdrive issues I have, similar to tdskip.

In my case, I bought this spare gearbox from a guy and I helped him unload his storage unit - the gearbox was on end, with the od hanging up in the air. Who knows how long. Plenty of old gear oil in the case but I suspect most if not all drained out of the od.

When I put in fluid and tested, it was pretty much gummed up and wouldn't operate. Then it started working. Plenty of pressure, 380-400 psi. I don't see erratic pressure behavior so I don't think it is overshimmed.

I think perhaps there is some goo on the brake ring or clutch keeping things stuck, it could also be weak springs but at the moment I'm hoping not. Could also be very old oil in the operating pistons that is slowly coming out.

I hadn't thought of ATF but I like the idea, thanks I'm going to give it a try. I can run everything with the driveshaft detached so I'm not straining the system much.
 
Sounds like a plan, Randy.
:thumbsup:
 
TR4nut said:
I hadn't thought of ATF but I like the idea, thanks I'm going to give it a try. I can run everything with the driveshaft detached so I'm not straining the system much.
Click to expand...

I freely admit I could be overly concerned here, but running ATF while the gearbox is in the car under load seems like inviting disaster. Personally, if I was going to do it it would be on the bench as you will be Randy.

Keep us posted, maybe some pictures of whatever that comes out with the flush.
 
I wonder if it would hurt the Tranny and OD unit to put kerosene in it to flush it out? if you didnt run it long


Hondo
 
Not something I would care to try. There are just too many places where steel rubs against brass. And kerosene doesn't lubricate worth a darn.
 
I had a Cosworth Vega and the recommended oil for that 5 speed was ATF. Not that the CV was a paragon of trans reliability (i had one lock up and send me off backwards into the AZ desert at speed) but I wouldn't be completely afraid to run it for a short while. I would think that you'd run some cheaper gear oil through it afterwards to flush the old ATF out before you put your better grade of oil in there.
 
Yeah, I'm going to try ATF as flush. Just need to pull the tunnel and seats to get better access. If it doesn't work during some extended testing / running in the garage, I'll yank it back out and put back the gearbox I had originally.
 
cheseroo said:
I had a Cosworth Vega and the recommended oil for that 5 speed was ATF.
Click to expand...
Interesting, I didn't realize they started that so early.

I owned a somewhat later GM product that took ATF in a 4-speed; but it used tapered roller bearings to carry the countershaft and, as I recall, didn't contain a single brass bushing or thrust surface in the entire gearbox. Even the shift forks were cast iron with plastic wear surfaces.

My point being that sauce for the goose isn't necessarily sauce for the gander.
 
So now I'm wondering....

What is different with newer transmissions that would make ATF okay for them and not for the older ones? It's all lubrication, and the ATF probably is a better lubricant. A lot of folks are running ATF or something similar in their TR7 transmissions. Does anybody know?

Dan B.
 
TR3driver said:
cheseroo said:
I had a Cosworth Vega and the recommended oil for that 5 speed was ATF.
Click to expand...

My point being that sauce for the goose isn't necessarily sauce for the gander.
Click to expand...

No question. I wouldn't run it in any manual trans except in this specific situation where it's possible that the detergent properties may clear up the sludged up problems of a long sitting trans. In my mind, if that fails the trans is coming apart anyway.

The T50 was new for the 76 Cosworth Vega. It had the same shift pattern as the old 911 with first towards you and to the back with the other 4 gears in the "H". It had a nasty habit of welding gears together internally. That's what happened to me one night where I may have been traveling above the speed limit between Phoenix and Tucson. One minute I was humming along, the next both rear wheels were locked up and I was headed backwards into the cactus and de-clutching did nothing. I thought the engine blew up because it shut off so suddenly but that didn't explain why pressing the clutch did nothing to stop the madness. That was a bit exciting. I'm pretty sure that was GM's first effort with running ATF in a manual trans.

They used to have a gigantic radar operated freeway sign in the middle of nowhere between Phoenix and Tucson that displayed your speed. You could see that thing from miles away. The thought was that since it was the middle of nowhere, people might be inclined to speed and if the sign showed them they were speeding, they would slow down. It had the opposite effect as people tried to ring up the biggest number they could and at some point they took it down.
 
DanB said:
So now I'm wondering....

What is different with newer transmissions that would make ATF okay for them and not for the older ones? It's all lubrication, and the ATF probably is a better lubricant. A lot of folks are running ATF or something similar in their TR7 transmissions. Does anybody know?
Click to expand...

I don't know for sure. But I do know that the countershaft thrust washers are a weak spot in the gearbox, with a definite tendency to premature wear. Once upon a time (1954), Standard-Triumph (and Laycock) specified that the OD (and gearbox since they share oil) required motor oil. But according to Ken Gillanders, an ex-factory contact told him that S-T changed to requiring "hypoid" oil (around 1960) because they were getting an unacceptable number of returns from the field for premature thrust washer failure. Hypoid oil contains additives that help protect against prolonged wiping contact under extreme pressure (which can wipe away the oil film with more ordinary lubricants), which is why it's more commonly called EP (for extreme pressure) oil today. (The hypoid name is because hypoid gear sets have the kind of extended wiping action that can break through the oil film.)

So my guess is that it is the presence of brass thrust surfaces that makes ATF unsuitable for the older transmissions. The A-type OD also contains lots of brass thrust surfaces. And even all ATF is not the same; using the wrong ATF can destroy an automatic transmission.

But really it's your choice. If someone wants to try using ATF and give us a report on the results after say, 100,000 miles, then by all means have at it!

Another option is to change the thrust washers in the gearbox to a roller bearing design. Oddly enough, Stags have roller bearings as original, and the TR6 housing can be machined to accept a Stag countershaft and bearings. (I don't think the same applies to the TR3 crash box, but it might.) I believe John Esposito's recommendation is to change to the roller bearings (not a cheap proposition) and then use motor oil.
 
Just a quick followup/closeout of this thread - the ATF suggestion by kellysguy seems to be working well. I swapped out for ATF, ran the od without the driveshaft attached for a while, then drained everything the next day and put in VR1 (50 wt). Its working quite well right now, I may go back to MT90 or other gear oil before the trek to Mitty in April, but for now I'm going to try and get some miles on the engine rebuild (200+ miles and counting).
 
cheseroo said:
The thought was that since it was the middle of nowhere, people might be inclined to speed and if the sign showed them they were speeding, they would slow down. It had the opposite effect as people tried to ring up the biggest number they could and at some point they took it down.
Click to expand...

HA!
 
TR4nut said:
Just a quick followup/closeout of this thread - the ATF suggestion by kellysguy seems to be working well. I swapped out for ATF, ran the od without the driveshaft attached for a while, then drained everything the next day and put in VR1 (50 wt). Its working quite well right now, I may go back to MT90 or other gear oil before the trek to Mitty in April, but for now I'm going to try and get some miles on the engine rebuild (200+ miles and counting).
Click to expand...

Great!
 
Yay!

Generally I don't have faith in those 'in a can' repairs. Fix-a-flat, valve job in a can, transmission tune-up in a can, etc. But this sounds like a very different story. Perhaps ATF stands for something else... I'm glad it's working and hope it continues. I know that engine looks great and still has that like new smell, and no oil leaks. Way to go Randy.
 
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