Car vs Truck Bellhousings (Cast Iron)
GM Cast Iron Bellhousing Identification
"505" Truck(left) "365" Passenger Car (right)
The truck cover (left) has a 5" center hole
compared to the 4 5/8 hole on the passenger car (Right)
Comparing Motor Mounting Bolt Holes
One of the major differences between the car and
truck bells is the motor mount bolt holes. With the
examples I own, the car mounting holes(right in picture)
are 7-1/6" and in a vertical alignment with each
other (when installed). The truck bell has a 1/2"
bolt hole and a pin, which are aligned horizontally
(when installed).
"365" "505"
The 365 housing (left) has a gusset between the
mount holes.