R Type Auto ATF ( Confused. Com )

[Rodney Siebert]

HI,
I am getting mixed advice on the best ATF for my 1954 R Type Auto. Some say use mineral ATF some say use modern synthetic ATF as its better, lasts longer & gives smoother shifts. Some say using modern ATF can damage the "phosphor bearings" in the gearbox ??) . Also it has been intimated that just emptying the gearbox from the gearbox drain plug only empties 70% of the fluid & you have to drop the gearbox pan to fully empty the gearbox prior to changeing the ATF ?. Can anyone please throw any experienced light on the subject.
Kind Regards
Double Jabbed Rodney

[Christopher Carnley]

There is a lot of bull excrement in talk about lubricants.

I this case buy Comma ATF. Or any other recognised ATF.

If you drain the sump you will only drain a bit of the fluid, as most of it is in the torus, ie the fluid flywheel/coupling,and also in the gear train parts.

It can take hours for the gearbox part to drip drain.

You should read the instructions carefully , and if you do a full drain, only start the engine with the hand brake full on and chocks under the front wheels.

If you do not have the Service Handbook or the Service Bulletins, you can download them from the RROCA site, Post War Technical Library. MK IV /R Type etc. FOC.

[Dan Suskin]

When you drain the torus - as you will need to - be extremely careful when you put the drain plug back in. It is very easy to cross thread and ruin. I know from bitter experience

[John Haydon]

Rodney, I have been having excellent results with my 54 automatic using Dexron III-rated fluids.

The 1950s manuals specified "Type A" but Hydra-Matic experts in the USA (it is a GM unit after all) currently recommend Dexron III fluids. Dexron III is listed as being backwards-compatible with Dexron II (which was backwards-compatible with Dexron I, and by extension, Type A).

I tried some generic Type A with terrible results, switched to a no-name mineral Dexron III which improved matters, and am now using Motul Multi ATF, which is fully synthetic. There has been a noticeable improvement in shifting, and some of its "bad habits" have disappeared.

When you drain the unit, expect about 5-6 quarts to come out of the sump and seemingly 20+ from the torus. Have a big drain pan ready! When it's warm the fluid will flow out relatively quickly. The biggest pain is taking off the lower cover over the torus, which holds the shift linkage on RHD cars. After half a dozen fluid changes, I can get it all done in about 3 hours, including raising the car and refilling.

As others have said, DO follow the instructions when refilling. Assuming you have drained both the sump and torus: Pour in 12 Imperial pints (14 US pints), then start and warm the car in Neutral and add a further 6 Imperial (7 US) pints. With the car running at slow idle, check the dipstick and add a bit at a time until the dipstick shows the fluid has reached the F mark. That is the second-biggest pain.

One last note: The gearbox on my car was replaced at Crewe in the 1970s, and the torus plug does not have the expected tapered thread! It is a 3/8" straight thread that seals with a copper washer. It may be the only one of its type... but maybe not.

[Rodney Siebert]

Thanks everyone for all their opinions & expertise, this all largely concurs with with all the known info out there.
Kind Regards
Rod