Roto-Hydramatic 10 Slim Jim

[Guest rlafash]

Is there anyone in the Wilmington, DE area familiar with, and capable of, rebuilding the Roto-Hydramatic 10 Slim Jim transmission in my 62 Starfire? While the car has only 55K miles, and transmission shifts well, there is a leak, probably at the front seal. My thought is that since the transmission must be removed and opened to correct the leak, I should have it completely overhauled.

[dlh61olds]

I know I will draw a lot of flak.

Before spending 2K on an overhaul which is usually of questionable quality

on the "slim jim" I would try this sealant.

White Shepherd Transmission Sealer Fixes Transmission Fluid Leaks | USA SEALANTS | Stop Leak for Oil Leaks, Blown Head Gaskets, Transmission & A/C Leaks

I have used it in both my transmissions and it works fine.

You will hear " fix it right" from the chorus, but, in my mind fixing it right is stopping the leak without damaging anything and at the least expense.

I also sealed a head gasket on a Ford Ranger truck with this company's Blue Devil sealer and two years and 15000 miles later it is still sealed tight.

If you are happy with your transmissions performance why would you want to overhaul it and risk compromising that performance??

Good luck, Dave

[joe_padavano]

Those "sealants" are simply solvents that cause rubber seals to expand. They will affect ALL seals that they touch, not just the front seal. How swelled internal piston seals affect shifting is not known. And of course the affect is only temporary. At some point the solvent evaporates and the seals return to their original leaking state (or worse, by that point).

Your call...

[rocketraider]

If it shifts well (or as well as a SJ can shift), I think you should be able to do a front seal job without a full rebuild.

[Guest]

One of the first places Roto Hydramatic's start to leak from is the small 8" fluid coupling. Roto's small coupling has very high fluid pressure compared to other automatic transmissions with fluid couplings, and also cars with torque converters.

They are a good innovative trans for their day and last without abuse as long as any automatic yesterday and today. Stay away from miracle fixes as Joe said as there is only the right way to stop a leak.

Don

[Guest rlafash]

I talked with an local, older, probably as old as me which is 66, transmission mechanic. He stated that the "most important issue with the slim jim is the governor. You must be sure that the governor is steel, not aluminum".

Does this make any sense?

[Oldsfan]

I'm thinking the earlier governors were aluminum, later ones were steel. I don't know when they changed over. They were updating those transmissions constantly from the time they were introduced until they went out of production. I believe the steel governors are better. I don't know how you tell, but I think they're first in, last out.

As has been said, if you're satisfied with how it works, I don't think I'd worry about it. Have the seal changed and leave it be until something dreadful happens (which may be never).

Paul