[55GMC-Truck]

Trying to find out if anyone knows about which engine type would be in a 1955 GMC truck. Thats about all I know about this truck. Owner didn't give me too much info when I picked it up.

[55GMC-Truck]

One thing I do about about it is that its an in-line 6. Heard it was a 250, 248, 271, and so on. Just getting confused

[smokin63]

There are most likely people here that can help you, But if you got to this website that is all they talk about is the ol gm trucks

http://www.stovebolt.com/ubbthreads/

[55GMC-Truck]

Apreciate it. Hoefully that helps

[CNC-Dude]

The GMC 6's have the cubic inch stamped on the pad next to the distributor! IE...248,270,302!

[techron]

Originally Posted by CNC-Dude

The GMC 6's have the cubic inch stamped on the pad next to the distributor! IE...248,270,302!

hey dude, just trying to dig this out of my dead brain cells--> , but wasn't there a 292 GMC I-6, i seem to remember racing one with a 348 chevy. i beat him but the 292 I-6 had awesome torque!!!

[55GMC-Truck]

So from what I have seen... The four engines that were availablie in this year were 228, 248, 250, and 271, and I think there was also a 302, but not competely sure. I do now know that this truck has an original 248 in-line six. Past that, haven't discovered too much more yet.

[CNC-Dude]

Originally Posted by techron

hey dude, just trying to dig this out of my dead brain cells--> , but wasn't there a 292 GMC I-6, i seem to remember racing one with a 348 chevy. i beat him but the 292 I-6 had awesome torque!!!

Hello sir, the 292 was a later era inline, the same engine family as the 230 and 250. The Chevy and GMC engines of the earlier years had several similarities, the most notable was they had only 4 mains in the block. The later more modern engines such as the 292 had 7 mains, and was a completely redesigned engine that had no commonality with the earlier engines. And you are correct, the 292's were very torquey. My good friend and many,many time NHRA national champion and record holder Cotton Perry campaigned a 292 in his "Pocket Rocket" Chevy II throughout the mid 1970's and early 80's. The engine was then put into current Comp racer Brian Browell's rear engine dragster in the early 80's, with Perry as driver, and continued to win more NHRA championships and more records. It was even featured in a Comp Cams ad in 1986, and was given the title as "The worlds quickest and fastest 6 cylinder", having just run an 8.04 at the US Nationals @ Indy against the late John Lingenfelter. Sorry for the history lesson, I just felt compeled to share that with you....

[sam-missle]

i believe the only 6 offered by gm in 1955 was the 235.

sam-missle

[CNC-Dude]

Originally Posted by sam-missle

i believe the only 6 offered by gm in 1955 was the 235.

sam-missle

Your partially correct! In that era, probably up until the early 1960's, Chevrolet and GMC were two different corporations that had there own seperate engine divisions and designs. The Chevrolet offered a 216,235,261 cubic inch divided between their passenger cars and trucks until 1962. The 261 being a Chevrolet truck engine only. The GMC's had the 228,248,270 and 302 engines as their engines up until that same time period! At some point after 1962, both GMC and Chevrolet merged their engine divisions or closed one and kept the other, how ever you want to look at it. And then all GM cars and trucks began to share a common "corporate" engine and finally ending up with a 350 based engine that was even in Pontiacs,Olds,Buicks and Chevy's in the 1970's and later....

[CNC-Dude]

Originally Posted by 55GMC-Truck

So from what I have seen... The four engines that were availablie in this year were 228, 248, 250, and 271, and I think there was also a 302, but not competely sure. I do now know that this truck has an original 248 in-line six. Past that, haven't discovered too much more yet.

The 250 and 271 you are refering to are not engines from that same engine family or era. The GMC engines of that time are 228,248,270 and 302. The 250 is part of the 194,230, and 292 engine design after 1962. The only thing they have in common is 6 cylinders. No parts interchange of any kind. The early engines are tough engines and worth fixing up, plenty of speed parts available....

[hardhatz]

I see everyone is talking about the sixes... GMCs also came with Pontiac V-8s, & Hydramatics. The 55 came with 287. My 57 came came with a 347.

[Chevrolet4x4s]

Didnt some of the GMCs have V8s,Do you have the vin number handy maybe we can decode it.

Shane

[55GMC-Truck]

Yes some of them did come with a V8... Mine has a 6 cilinder-inline 248. The vin is 152PY687, which comes up with ten different answers. So tht probably won't do any good. But the final answer was 55(second series) with a 248! That came from Stovebolt... Which seems to be the only one who didn't tell me its a 61 chevy or 59 pontiac