I do love me an old pickup truck, and this one is a gem; I mean a GMC. And not just any old GMC, but a 3/4 ton, 4×4, four-speed manual, hi-low transfer case, with an 8′ Stepside bed and the legendary GMC 60 degree V6. Does it get any better than this?
I’m guessing at its year, as I can’t find any real difference between the ’64, ’65 and ’66 Jimmys. Maybe someone else can. And although these look a lot like their Chevy cousins, back then there was a genuine difference…under the hood.
The legendary GMC V6 resided in these, instead of Chevy sixes and V8s. I covered the story of the GMC V6 in depth here, so I won’t repeat it all here. Unlike the odd-fire Buick 90° V6, this one was a proper 60° design.
It was designed for serious truck work, built beefy and with plenty of cooling capacity to handle the tough loads that the larger trucks placed on it. The one in this pickup is probably a 305 cubic inch version, but displacement went all the way to 478 cubic inches. Oddly, there was even a V8 version with 637 cubic inches, with twin balance shafts to compensate for its uneven-firing and vibrations, due to its 60° block. They were all relatively low-rpm engines, with some versions producing their maximum power below 3000 rpm. The M “Magnum” series that appeared in the mid-sixties had bigger ports and valves, and less constricted exhaust headers, and are the most powerful and desirable of the family.
And there was the really legendary 702 cubic inch “Twin-Six” V-12. Its story is here. It’s essentially two 305 CID V6s, sharing one large block, but using two sets of V6 cylinder heads. It churned out 275 hp at 2400 rpm, and a mighty 630 ft.lbs. of torque at 1600 rpm. It was used in large trucks and fire engines, and became a favorite for stationary pump sets. It essentially knocked the truly legendary Hall-Scott gasoline engines out of those roles, as it was much cheaper and still held up well.
One half of the biggest and gnarliest gasoline truck engine in the land is at the beck and call of this driver, as well as a tough four-speed truck transmission and transfer case. And I’ll bet it doesn’t have power steering.
This one is working up some nice contrasting color patina.
When I was thinking of getting an old pickup almost 30 years ago, I vacillated between a GMC/Chevy or a Ford. But I wasn’t too keen on the fact that GM was still using wood for the beds in their trucks.
It does go bad, especially in our climate. Meanwhile, my Ford’s tough steel bed is still going strong.
There’s only one downside to this truck: it must ride like a bucking bronco. Back then, 4×4 trucks had extra stiff springs on their jacked-up chassis, and this is a 3/4 ton. Even the half-ton 4x4s rode hard. Oh well; nobody’s perfect.
More GMC 60 degree goodness: