What you are thinking of is the B2 piston and, unfortunately, there's no quick and dirty trick for installing one in the field. The tranny must be pulled(or at least the back mount pulled and the rear of the tranny dropped far enough) to access the B2.

However, this does not sound like a B2 failure. The B2 piston failure generally manifests itsself in this fashion:

—Catastrophic failure of transmission in forward gears
—Partial engagement of forward gears, with slippage progressively reduced as transmission is shifting from 1-2, 2-3, and 3-4.
—Reverse gear engagement normal

If I were you, I believe that I would start this project by draining the transmission fluid, replacing it and adding Trans-X. Of course, if the existing fluid looks like Pepto-Bismol, you are sunk. Pink, strawberry milkshake fluid indicates an engine coolant leak into the transmission.


Good luck!

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Never a dull moment at Berry Hill Farm.