The Stovebolt Site Forums The Parking Lot Big Bolts Clark 5 speeds

I found a '78 Chevy C60 for sale for $300 about a half hour from my house. Runs/drives, has a 350/2bbl carb, and what the seller says is a 5 speed Clark tranny. No bed, just the cab and chassis.

Anyone know what models or ratios this could possibly have? I know it *might* have an OD, but I am not holding my breath. Seller says it has a granny 1st, so I am really not holding my breath.

However, since this truck has a 350, the tranny should bolt right up to any Chevy engine. I am thinking of going 292 and think this tranny will eliminate the missing gear in my sm465, which would be pretty nice all around.

any help would be appreciated!

http://www.6066gmcguy.org/SM420.htm

toward the bottom of this page they list 5-speed info. there are about 15 different clark model#s, and only one lists an overdrive gear (.80). you can usually find the make and model of your trans by creeping under your rig with a flashlight, that's how I found the designation on the 5-speed spicer in my 68 C60. By the way, what kind of shape is that 350 in? I might be interested if you're swapping it out...

Clark 282 and 285 were very popular with Chevrolet & GM during that period. As Sawby said there should be a tag on the trannt case.

I feel a little stupid, I have been to the 60-66 GMC page many times to look at the Spicer 5831 stuff :o .
Thanks for the link!

I didn't really get a good look at the truck. It was rainy and the guy happened to be outside. He started it up, didn't seem to smoke, but thats about it.
I think I will go back and look more closely at the tranny.
Thanks again guys.

300 bucks for a running medium duty truck? i'd buy it if it had 8 hamsters under the hood and rubber bands for a tranny

I spent a lot of time looking into clark transmissions a few years back. I even wrote up my findings for this website, although I don't know if it is still around. I had talked with a shop that specialized in the trans, and typed up what he said. I'm doing this all from memory, so double check the information.

The overdrive versions were usually in delivery trucks or over the road trucks, not farm trucks. The overdrive wasn't all that common, but it wasn't rare either.

The overdrive ratio was .80 (20 percent overdrive), no other overdrive ratio was available.

The tag on the overdrive transmission will usually have a VO or O on the end of the tag number, except for later versions. Later versions have to have the tag number deciphered to know if it was an overdrive.

Later versions are significantly larger than the SM465 transmission, which came in most 70s pickups. I doubt that they would fit under the transmission humps of most pickups from 47 to present, but would be OK in 2 ton and up trucks.

Earlier versions were about the same size as the SM465, but some earlier transmissions were not synchronized, so be warned (double clutch it).

It probably has a 2 speed axle. You would not need o-drive with it. Why would you change from a 350 to a 292? Those Clark trans. are tough & easy to rebuild.

Dave, in response to your remark about the trans having a granny gear, it seems that all the clarks had what could be considered a granny gear (in the 6 or 7:1 area), regardless of overdrive or not. I think those transes go back to the days of getting huge loads moving with relatively small 6-cylinder engines, and are therefore geared deeply on the bottom end

Wow, thanks for all the replies guys!

To answer some questions, I am doing a slight re-vamp of my truck. The existing 350/SM465/Rockwell T221 all pretty much died (350 seized, 465 needs a new output shaft, Rockwell swallowed a bearing).

I am getting a free divorced NP202 from an IH with a PTO and 1410 yokes.

If I can work out the deal on this truck, it will go in front of the 202.

As far as the 292 goes, my dad has a Ford F150 with the 300 inline six, and I love that thing. So, I'd like to go to a six...and it helps that I know where I can get a '69 C/30 for free with a 292/465. I never really cared for my 350...stock, but it was a pig and got horrible mileage. I'd like to try the 292.

Thanks again for all the help. Hopefully I will go see this truck again this weekend. The only thing that may prevent me from getting it is money. Being a college student sucks. Even $300 (+ temp tags, registration, GAS) will be a big hit to my wallet.

Again, thanks! This place rocks.

Dave, I hear ya man, I graduated from college last May, and even though i'm working now it seems like my wallet is even smaller. But, like I said, if you get the C60 and its 350 isn't too dogged, I can offset your cost by buying the motor. it's good to see another college-age kid interested in old GM iron, i went to school in suburban philly and you don't see much of that around here.

If its a Clark 280 series with OD the 4th and 5th possision are switched. That the way the one I have is.
Later Willis

Vaughn -- I remember that tranny info you sent in -- It may have been lost when we had the lightning strike that zapped the computers here. Do you still have it?? I'll look again, though -- it might be hiding on the server somewhere.

Thanks,
John