The Stovebolt Site Forums The Parking Lot Big Bolts GMC 270 swap into Chevy Big Bolt

I understand that the GMC engines are slightly longer than the chevys and that in pickup trucks it is necessary to relocate the radiator to swap in a GMC engine. My question is whether that is still the case if swapping a GMC engine (probably a 270) into a chevy big bolt (6400)? Or, is there extra space under the hood of the larger trucks to accommodate the longer GMC engine?

Hy Clark6400, please tell us the year of the truck you are asking about.

If the Chevy engine is still in the Chevy truck measure the distance from the forward most point on the Chevy engine (probably the leading edge of the fan blades or the fan mounting bolts) to the radiator. That dimension is an inch and a half longer on the GMC. Don't forget to have enough space to get the fan belt through the gap when you are changing it.

Thank you. Truck is a 1953 6400. I'll double check but I don't believe there is that much 1.5 inch of additional space between front of fan and radiator - so it sounds like the position of the radiator would have to be moved just like it would on a pickup of same year/era.