Anyone ever put some kind of coating on a valve body separator plate to have it seal it up better?

Did a simple air pressure test today on a 42RH and noticed tiny air bubbles come out from between the valve body plate.

I can only imagine how much it would leak when the transmissions is in operation.

Started thinking about a coating or extra layer, working as a gasket which would seal the plate better between the valve body halves.

Don't worry about the minor leakage, there's enough volume available to supplant it. On the plus side, minor leakage keeps the fluid moving so is gets back to the pan for cooling.

I know millions of Mopar transmissions have been used like this without any/much issues.
Was just thinking if sealing it up better would improve the transmission's (shift) efficiency perhaps so oil pressure isn't wasted by major internal leakage and more of it stays available for clutch application and lubrication where it's needed most and such.

I mean, there has to be a valid reason modern transmissions come with valve body plate gaskets thesedays...




Maybe I'll have a go at scanning a valve body plate and digitally cut two gaskets for it to surround it with.
Or maybe just get some thin gasketmaterial and punch/cut out all the holes.

You didn’t say where it was leaking so depending on the circuit, sealing it up may help.

Later model transmissions being electronically controlled and much more precise than the old units, the reason for the gaskets is to keep the valve body sealed up so the electronic algorithm works the same for all the transmissions of a given family.

I noticed the bubbling/leakage near the accumulator, when air pressure was applied from the outside of the housing (plug removed). The valvebody there is surrounded/tightened with 4 bolts.
Transmission was drained some time ago already.

IMO if leakage can occur there, I'm sure there's bound to be more leakage occuring inside the valvebody to adjacent channels.

air will find it's way through places that liquid cannot or at least at a greatly reduced volume/amount

In most cases there isn't sufficient volume of leakage to create enough pressure to cause a problem.