Originally Posted by Truckrolet
It was offered in 1957, and the truck shop manuals from then on had the overhaul info in them, up until it was not an option anymore.

The Powermatic (Allison) 6-speed automatic was first offered in a Chevrolet truck starting in 1956...It's also in the 1956 Supplement Shop Manual.

Mike B smile

Mike Boteler

1956 Chevy 3100 Resto Rod
1952 Willys M38 Army Jeep
1983 Jeep CJ7 Laredo
1984 Jeep CJ7
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Silver Spring, MD