Blue devil Transmission sealer

[Sergio Santos]

Hello anybody has a experience using this Blue devil transmission sealer on 1950  Buick  roadmaster with  Dynaflow transmission leak ?

[Larry Schramm]

Generally all of that additive stuff is questionable. 

 

Best if you are going to keep the car is rebuild the transmission and fix it right the first time.  Fix the problem and not try to fix the symptom from a can.  Just IMO

Edited April 23, 2020 by Larry Schramm (see edit history)

[old car fan]

Snake oil.fix it right

[Guest]

Hi Sergio,

                   I am not familiar with Blue Devil brand but I know Lucas makes some good transmission products. If a rebuild is not in the budget it certainly won't hurt to give it a try. I have used transmission additives when I've bought a car that has been sitting for a couple of years. They will usually do what they are intended to do, soften up dry or hardened seals. The turbo 400 in my truck was a little slow going into reverse but otherwise worked fine. It was parked for two years before I bought it. I used the Lucas brand additive and it softened up the rear piston seal after a few days. Shifts fine now. Some of these additives will stop leaks by softening up dry gaskets. It just depends on how severe your leak is. I say give it a try before you go to the huge expense of an overhaul. You just may get lucky.

Greg

[joe_padavano]

There is no magic additive that "fixes" seals. All any of these transmission stop-leak additives do is soften and swell the existing seals. This will stem the tide for a while, but the fact that the seal is now softer than original means that it wears out that much faster. An additive may be an expedient (if unscrupulous) "fix" for a car you are about to flip, but certainly not something I'd use in a car I cared about.

[old car fan]

Snake oil,the only thing that fixes it,is the fix.