Fuel leak at the IP on my 91.

[Mr_Roboto]

In the IDI years, a Superduty and an F-450 were one and the same, with ten-hole wheels, straight front axle, and front leaf springs.

Later on, Ford used the SuperDuty name on their new body-style of trucks, regardless of weight capacity.

The F-450 badged truck was not produced until the 1999 body style. The 10 lug trucks before that were badged "F-Superduty" and while similar, are not the same as the F-450. In particular, the F-Superduty uses 16" tires while the F-450 uses 19.5" tires, for a vast difference in max load capacity.

I have the 1994 Ford factory service manual, in every case the truck is referred to as F-Superduty and in no case is it referred to as an F-450.