Re: trans troubles

Posted by Dave Brownell On 2015/11/9 19:18:47

Take heart, there are more than a few of us with 1956 Ultramatics that have dried out direct drive clutches that will "grumble" right after that upshift if the accelerator isn't slightly relaxed as the direct drive clutch engages. After a couple of years, lifting my right toe just a bit has become second nature to me. It's a small price to pay for not removing and opening up the transmission for a quality rebuild.

For those of us old enough to remember riding GM diesel buses in the 1950s, this "lift the toe to shift up" activity is almost nostalgic. As a kid I asked a bus driver if it was necessary and was told that it was. I believe that their Allison transmissions had only two speeds and was just as slushy as any Dynaflow, PowerGlide or Ultramatic (1950-1953, before Gear-Start). But they were durable and endured millions of miles of the toughest city bus routes and drivers. When the previous owner-mechanic told me how to do it in a Packard, it was deja vu all over again.