I don't know if "double-shifting" is the appropriate word to use, but the
4HP22 tranny in my 88 505 STX has been, on occasion, doing the following:
during hard acceleration the shift from 3rd to 4th is not "announced" by a
single mild shake, but by two of them, one right after another. Under normal
acceleration, the shifting is almost seamless.
Anyone been through this before? Thanks for your time.
RB in Austin, Texas