did gmc make a v 6 in the 1960's

Yes it was a 305 cu in v6 .

yes back in the early 60,s they had one that they used in some of the trucks,i had one long time ago,they was tough old engines,if l can find any info on it, l,ll post it,mine was in a 66 gmc,very good engines,good luck.

Yes. They did.
http://en.wikipedia.org/wiki/GMC_V6_engine


If you mean GM and not GMC (GMC is a part of GM), then they had another one, as well.
http://en.wikipedia.org/wiki/Buick_V6_engine

This engine is the direct ancestor of the well-regarded 3800 V6 found in such cars as the Pontiac Grand Prix, 20th Anniversary Trans Am, Buick Grand National and such.

the earliest GM v6 was started in the buick, it was not 305ci. It was a fireball 198ci (3.2 litre), it went up in displacement a couple times but it was never 305ci, thats a GM V8 powerplant

No, a 231 cubic inch V-6 (3.8 liter) came out in the mid 70 is but the inline 250 cid 6 (4.2 liter) was around for a long time .The so-called oil embargo lead to some downsizing of cars & engines as well. The 231 cid V-6 was a 307 cid V-8 minus two cylinders.
They have been around for 25 plus years & have gain lots of muscle with turbos & super chargers , the 86 Regal GNX with & intercooled/turbo charged 3.8 V-6 was one second faster to 60 mph then the Corvette of that same year, & got 20 mpg's

Yes they did. It was a truck engine and a very good one too. These engines are in demand even today. GM even made a V12 from the V6 design parameters.

Yes GMC made the v6 in many different displacements. 305 and 401 were 2 of them. Buick made an aluminum v6 which is what the 3800 is based off of.

Yes, they ranged in size from 305, 351, 379, 401, 432, 478. As said above, the V6 is were mated together to make V12 motors used in farming applications (pumps, special drive system, farm implements).

Here is a link full of useful info:
http://6066gmcguy.org/