I have a 55 GMC pickup with a 248 6 cylinder engine, 3 on the column, and would like to replace the engine with a 55 Chevy V8 265 engine. Looking for any information on how to set the engine in the 55 GMC frame/motor mounts or any knowledge on the extra holes in the factory motor mount. Was the motor mount made to house either the inline 6 or a V8? Any pieces of knowledge on how to find possible mounts that would work? Looking for a way to use the existing holes in the GMC 248 frame to mount the 55 Chevy engine? Any knowledge, suggestions, or guidance on where to look would be greatly appreciated.
I'm assuming your 55 GMC is a 2nd series (looks like a '56) and not a 1st series (looks like a '54). The motor mounts for the 2nd series GMC engines, both the 248 six cylinder and the 288 or 316 V8, both had a center front mount and side mounts on the bellhousing. Frames are the same from 6 to V8. You will definitely need to install custom mounts for the 265. I wouldn't bet my life on it, but I don't think either GMC bellhousing would bolt to the Chevy block without some kind of adapter. Just curious, why a 265?
I have a 248 GMC 1955 with 3 on the column, had the engine rebuilt 2 years ago, and have had oil leaks ever since, even upon taking back and supposedly being fixed 2 times. Now oil even comes out of the exhaust. Only about 2,000 miles on the engine, doesn't sound right, and over $3,000 into it. I have a 265 V8 motor with overdrive transmission, 3-speed standard taken out of a 55 Chevy, ran well when I parked it over 10-15 years ago. So to answer your question I have the 265 motor on hand, right now sitting in the garage it which I start period and sounds good. (no oil leaks)
