Gmc V12 in trucks
 

I'm a newbie but did gmc actually put V12 in trucks I've never seen a pic of one in a truck

Re: Gmc V12 in trucks
 

Yes, 7000 series trucks, minuteman missile transporter, fire trucks.

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Since I have this in one of my photo collections here's a pic of the GMC MinuteMan Missle transporter. I remember seeing them many times around here back in the day.

DAC

Re: Gmc V12 in trucks
 

I know a guy that has three of the transporter tractors, I was going to buy a v12 out of one with 10k miles. I thought about buying the tractor but ,not sure what I would do with it. He changed the gearing so you can run down the highway65+ before 45 mph was tops.

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Where they common in more mainstream gmc heavy truck like tractor trailers

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Wouldn't say they were real common in over-the-road trucks, but they were out there. Kingsway up in Canada ran them for many years:

http://www.hankstruckpictures.com/kingsway.htm

I think Texaco and/or Mobil used them to pull tankers as well. Regardless, I think a lot of the V-12 powered trucks ended up as fire apparatus, where large gasoline engines were favored over diesels until the 70's.

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Our county had 5 tandem dump trucks (65's) WITH V12'S

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Are there any pictures floating around?

Re: Gmc V12 in trucks
 

There are some online.

Just google 702 V-12 GMC and hit Images.

The V-12 ended when the 637 V-8 was introduced which I believe was in '66.

I used to drive a '71 with a 637, but never had the opportunity to get behind a V-12.

Bill

Re: Gmc V12 in trucks
 

Here is a GMC L-7000 with a Tinw-Six

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GMC B-7000 trucks with Twin-Six

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More B-Model GMC 7000s, the 2nd one was scrapped, but the engine was saved.

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Last B-7000 I have photos of showing the engine

Re: Gmc V12 in trucks
 

1960s GMC Minuteman Missile Transporter powered by the GMC Twin-Six Gas Engine.

Here are some photos I took of the one that use to be at the Hill Air & Space museum, it was sold for scrap just this past year.
1960s GMC Minuteman Missile Transporter

Re: Gmc V12 in trucks
 

I really like the B 7000 trucks. Are these trucks still around that you took pics of. I know of a Minute Man Missile transporter tractor that could be bought, It has had the gearing modified to go down the highway 65 -70 MPH, top speed was about 45. Not sure What I would do with it.

Re: Gmc V12 in trucks
 

Here is one I have setting for a future restore project. Engine runs, but needs carburetor work. It is a 1962.Attachment 5972

Attachment 5973

Attachment 5974

Attachment 5975

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Nice B-Model, and nice collection of trucks you have in the back ground.

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Thank you. That is just a few of them. Got more hidden away.

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Good stuff.

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Awesome L series. I see that it is setting in front of the 66 v12 powered pickup Where we these taken?.

Re: Gmc V12 in trucks
 

Attachment 5998I took those 2 big hunks of iron to a car show in Wis in 2012. The wife drove
the long nose and I drove the L7000. If you drive the L7000 without a load, you
should have a real good chiropractor.:ahhhh: The little Rap'em Pappy long nose rides and drives just as good as her Buick she says. The old V12 can cruise the Indy Brickyard sweet also.

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I did not know the L 7000 was yours. I have seen a lot of photos of your pickup but have not seen the L 7000. I have been down to visit Marvin Taylor in Guyman Ok a couple of times, Marvin said you brought your truck down there to take a picture with his 46.

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Love the must-be-rare "Size Matters" Emblem :dryGMC:

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Bobdylan,
Yes, Cayoterun and I did alot of brain storming and hair scratching to build
Balaur and Rap'em Pappy. His is the best mentor a guy can ask for. The greatest
guy for helping save these old V12s. We spent a day in Boise,Ok at the museum
where he donated his 62 V12 Balaur. It was on our bucket list to put the 2 trucks
together. We drove them around and talked V12s all that day. One of my other trips, I helped get the 46 V12 he calls Thumper wired up and cruising.That is a cool truck. Now if you or anyone has a extra 305v6, Speedway museum in
Lincoln, Ne is looking for one. I followed Cayoterun's footsteps and took a V12
there last year. I offered a 401,but they wanted a 305. They want to put the large V12 and small v6 on display together on 3rd floor. That will help these GMC motors to be not forgotten.:oldman:

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Funky61

How where you able to read that? That does get a lot of smiles.

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Marvin took the kids for a ride in thumper, we wanted to go out to the museum but ran out of time.
I have a 305 I would donate. Just need to figure out how and when, I am planning on taking the family to Pioneer Museum in Minden Nebraska, maybe we could go to Lincoln from there.

Re: Gmc V12 in trucks
 

speedway museum

Re: Gmc V12 in trucks
 

Very cool Pappy! You and Cayoterun have some of the most clever GMC's I've ever seen. I'm glad to know that the "Museum of American Speed" is still in good hands after "Speedy" Bill Smith's passing. He loved the less common engines of all kinds, and worked hard to preserve as many as he could right up until his death. One of the sprint cars in that museum raced at our dirt track clear up into the early 1980's and was powered by a brutally fast 270 Cu. In. GMC I-6. Jolly knows the car I'm talking about as it also raced in his area and if I remember correctly, his father raced against it.

Thanks for posting your trucks.

DAC

Re: Gmc V12 in trucks
 

RAP'EM PAPPY - next time you have your trucks out to play with I'd like to take a closer look at them. I live three, maybe four miles south of Sun Prairie!

I rode shotgun with Dad hauling livestock to Chicago stock yards and packing plants all over Iowa and Illinois as a kid. I forget the year, was mid/late 1960's but we went to Chicago 50 Sunday's one year. Lot of big V-6 GMC's, Ford's, lots and lots of Binders. I only remember hearing a rumor about one V-12 GMC owned/used to haul livestock. Gas tractors were favored by most livestock haulers back then, many older farmers believed diesel exhaust harmed cattle especially, and tainted the meat. By the early '70's that idea faded and the gas trucks disappeared.

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Powerstroke, I will contact you this summer. We can talk GMC's and maybe
I can convert you into owning one.:upyes:

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Just shoot me a private message the day before or a couple hours before.

I REALLY like the looks of that L7000!. I'll bring my camera!

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Just like to add it was B series conventional cabs and L series Tilt Cabs that had the 702 V12 that was available from 1960-65.:ok:

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I don't know if Rap'em Pappy hangs out here anymore but I saw his V-12 pickup being hauled on County N around the I-94 traffic circles about 10:30 AM, Yesterday, Thursday, about 7 miles south of the east edge of SP. Have a lot more interest in the pickup now that I caught a glimpse of it. I'd still like to bobtail around in the tilt cab, hear that V-12 doing what it was built to do. My next door neighbor always has a semi-trailer or two sitting in his yard we could hook to to smooth the ride and make the tilt-cab bark a little.

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As I was reading over the posts in this thread, I was reminded of a story my late father told about this engine. During the '60s, my family was the GMC dealer in Cullman, Alabama. Not only was the dealership a light/medium duty dealer, but the dealership was also a designated heavy duty repair station for both gas & diesel engines. In '62 or'63, dad was called out on a service call to repair a B7000-V12 truck at a local truck stop on north US 31(no interstate highways). This particular truck had tuning problems, being that previous mechanics had not properly tuned the engine. Dad re-tuned the engine, re-run the overhead, set the carburetors and timing, all the while being strung out underneath the cab of the truck. The owner said upon starting the engine after dad finished that was the best that engine had ever run. Dad said it took someone who had factory training (at that time) to properly tune these engines. BTW, my dad had over 30 certificates of training from GM Institute during the time we had GMC.

Re: Gmc V12 in trucks
 

Howdy, and Welcome to the board!

A word of Warning! V-12s are addictive!

First, V12s are fast becoming extinct. Only built from 60-66. If a person can get one running regardless of use, you have a automotive living, breathing dinosaur. The engines were very durable, and I like the unique design. The "twin-six" came from the fact GMC used all components from the 351, hence, 702, Twin six on one block, crank, camshaft, ignition, and oil pan. All other parts are inter-changeable.

Many were used here in the plains states on Ag. irrigation wells. and burned natural gas. I worked for the farmer and cared for the motor that's in the '46 Chev. when it was new in '65. It pumped 2200 gal a minute for 22 years with one overhaul bored .30 over.

When we checked them at night, the exhaust manifolds would be glowing cherry red. If there was a weak cylinder, the manifold would have a darker spot at that one than the rest.

I keep it in our metal shop. When people come with smaller kids to see it, I'll start it up, let it warm a little, then gradually start speeding it up. When the metal on the shop starts to rumble about 2100, close the throttle real quick, and then back-fires, blowing fire out the 4 exhaust pipes, that's when the stampede starts for the door.

It doesn't take much to keep an ol' retired farmer entertained, Huh, Rap-em-Pappy?

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Hi Coyoterun and powerstroke, Just give us old farm kids a wrench and
a old truck.....Just like a duck in water having fun. Yes, I took old Rap'em Pappy for a road trip to Lexington, Ky. There was a Goodguys show at of all places, Kentucky Horse Park. You might say I was just horsing around. This is a 1200 acre horse playground. With horses worth more than any vehicles there. With up 2000 vehicles there, NOT one other GMC V6, only my V12.
I always get asked about gas mileage. But I always tell them,,,about 25 to 30
thumbs up per gallon. :welldone:

Re: Gmc V12 in trucks
 

On my '62 6500 with the 478 V-6, once in a while when driving a hi-way speed of about 55 to 60 for a length of time and then coasting some slowing down for the exit ramp, it would let out a back fire equal to an M-80.

The first time it happened it sure scared the heck out of me.

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Rap'em Pappy - Sounds like a FUN weekend. Pretty country around Lexington, Ky. My sister went to U of K there for a couple years. It's just crazy what horses are worth isn't it?
I hope you run into Dennis Gage sometime at a car show with Rap'em Pappy. I'd like to see him speechless on TV! He would be familiar with the stock truck.

SON went thru his mid-life crisis this summer. Traded his '14 Ram 2500 CTD off on a '18 Mustang GT with Performance Pkg #2, Recaro seats, Big Brembo brakes, Big sticky Pirelli tires, 305-40x19 I think. 460+ hp, 6 spd manual trans. All kinds of electronic stuff like Launch control, RPM matching for each shift, twin disk clutch. Anyhow, he still needs a truck. So I gave him my '96 F-250. He pulls his Mustang up to the gas pump a few people look but don't say anything. He pulls my old truck up to the pump and a crowd forms! It's kinda ticking him off! Just proves Trucks are COOL!

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Thanks, BillT for a good belly-laugh to start the day. Did the floor boards shake, and you looked in the rear mirror to see how much pig iron was scattered on the pavement??

Since on wells, the motors ran a constant speed, we'd tune them at night and use the exhaust as a guide. With the stub pipes on each head, blue flame would be at the pipe tips, so we could tune each distributor on each side of the motor, by tuning in each distributor to max blue flame.

Re: Gmc V12 in trucks
 

Was looking in the mirrors for sure, lol.

I don't know why it didn't blow the Mufflers apart. Maybe because they were Straight-Thru Duals ??