The Stovebolt Site Forums The Parking Lot Big Bolts Interesting YouTube video on 1966 C-60 Road Tractor

Check out this video of a '66 C-60. Two strange things. First one is that I've never seen 5-10 Wheels on a Road Tractor before and of course the truck has Air Pressure, but am I seeing Hydraulic Brakes on it?

www.youtube.com/watch?v=jFC8RU84WQI

Maybe air over hydraulic on the tractor, and air brakes controlled by a steering column valve on the trailer? Oddball setup if it is!
Jerry

It certainly looks like it was modified with the additional compressor. Original tractor probably had AirPack air over hydraulic, then someone added another compressor and lines for full air brakes on trailers.

The extra compressor is for an aftermarket under dash air conditioner. One of my first paying jobs back in the early 1960s was the inside guy on the installation of the Mark IV add on air systems that Dad's shop sold. I would hang the evaporator under the dash and route the wiring, while a more experienced guy did the under hood work- - - -compressor, condenser, lines, control valves, etc. We would start on a job when the shop opened in the morning, and drive to lunch in an air conditioned car- - - - -come back, and install another one in the afternoon! I was 14 years old at the time.
Jerry

Yup, now I see the evap cabinet and the refrigerant hoses. The tractor does not have full air brakes so they are either AirPack or no assist. By the time I was driving medium duty GM trucks from the early '70's, they were full air.

Wondering if the truck came that way from the factory? Or did someone just convert it into a road tractor? If it's possible to tell.

I'm building an air compressor mount in the engine compartment of the F-450 truck with the 10 foot service bed I just bought- - - -not for brakes, but it will have an onboard air system for impact wrenches, etc. There will also be a 120/240 volt AC generator and a gasoline powered welder.
Jerry

I think this was a yard hauler, meant only to jockey trailers around the service lot. It needed air to unlock the trailer's brakes, however it wasn't taking them very far or very fast, so the truck's brakes were enough. Interesting how someone installed air conditioning, too!

Could have been a yard tractor but with mudflaps and 100 gallons of fuel it looks like it was used on the road.

For anyone interested, there is a bunch of truck data and options info in this 1966 Chevy resource document. If I read it correctly, the air over hydraulic brakes (AOHB) were an option for this C60 model. The 366 Big Block was also optional for the C60. There is also a chassis diagram showing the 5-10 wheels.

Good info. I see the Air over Hydraulic option for the C-60. Interesting that the 4-53 Detroit is no longer available in '66. Probably because of the new 366 Big Block option. Of course, I say that was a mistake, lol. The should have kept the Detroit, but strangely it was only available in the C-50.

BTW, I like the picture of the Flat Bed Trailer carrying lumber in the link. Although in my '62 GMC 6500, I would haul those units 3 high !!

The 366/427 truck motors were/are real truck engines, designed for heavy use, they withstood a lot of abuse in medium truck use.

Back in the '90s when I decided to get my bus a more powerful engine than the stock 2bbl 327, the first thing I did was look at the Chevy/GMC medium duties that all the wrecking yards had at the time. Every one of the 427s had the same spun main bearings and valve train issues that the '70s BBC pass car engines had. And because it was a BBC, a buildable core was $2500 without the heads.. so I thought, oooh I could sign up for more bottom end issues, valvetrain issues, oil usage, and all the other old school big block foibles.. or just go through one of the Cadillac V8s of which I had a yard full. Designed from the start to be 500cid (actually, was designed to be increased to 600, but then the gas crunch hit) and to run for hours without trauma at exactly the RPM range typically encountered in a bigger rig. Most of 600lbs/ft by 2000RPM, and it turned out not to mind having a manual gearbox behind it.

I had to have the Chevy flywheel machined to match the Cadi crank, but once I did I was able to keep the huge, bellhousing mounted original starter. The flywheel face to back of block distance turned out to be the same, I think it's a GM standard from 1948 onwards along with the guide pins also being spaced the same throughout divisions. The factory installation even had a steel adapter plate from Chevy block to big round 2 ton bellhousing-I had only to drill a couple of holes! Once done, the adapter plate bolted to the back of the block and then I could bolt that assembly to the bellhousing.

I sure was grateful for the hydraulic clutch! That made things so much easier versus having to recreate the ball stud that a Chevy block would have had a hole for.