1977 Chevy C60

[David A Young]

Ok guys I'm having a bit of trouble finding a part for my grain truck. The speedometer doesn't work. It has a 2 speed rear end and the reducer for the speedometer is locked up. I have dissassembled the reducer and cleaned it but it still doesn't spin. And the cable end is broken off inside (noticed that when I pulled it apart) it was just riding inside it. And I need a part # if anyone has one because every time I try to run the number i can't even get a pic of it to come up on Google. I have a gm service manual too and it shows a wiring diagram and nothing else. So if anyone has a number I wound appreciate it. Needing to get it going for harvest season. 1977 c60 350 ch465 2 speed rear. Thanks.

[Stewart G Griffin]

If you're wanting to keep everything original i can understand.   But have you considered a GPS speedo?   Would be much simpler to get things running.

[FlatBlack77]

or you could buy a cheap dash mount GPS.

on a side note i would like to see some pics of the truck i love the big old C60s

[big_al273]

i'm going to suggest you go to your local heavy truck scrap yard and start looking there, even if you get a part number i don't think it will be easy to find a new unit

[David A Young]

In response to some comments yes I'd like to keep it original, but I figured posting here would be a last resort thing. If I don't find a way to fix it I will run a cable directly to trans and it will just be off and I'll put up with it when I've got the rear end in low range. Ill try to post some pics either today or tomorrow. My schedule is kinda hectic right now with school and work and vehicles lol.

[1967KaiserM715]

Our reducer in our 69 C60 blew apart, and we couldn't find the right parts. But you may be able to try any big rig shop and see if they can find a substitute,  I know the older Macks ran a similar reducer with their split rear ends

Sent from my LGL34C using Tapatalk

[bd]

Agreed.  Many of the parts are obsolete.  Go to a local full-service speedometer shop that repairs medium truck speedometers.  They may still have the necessary pieces and be able to sort it out for you.

[David A Young]

Ill try to snap some pics for the guys asking for pics. I think we might have a scrapyard around here that has two tons but I'm not sure. I figured most of them were obsolete but I figured I'd give it a shot. The truck is in really good shape and I'm wanting to fix it up but if I can't find the piece for the speedometer I'll more than likely end up putting a whole speedometer cable in it so that it will work. It would read right in high range then but be off in low.

[hatzie]

The MD and the LD share speedometer cable parts.
New Ratio boxes and Speedometer cables and attaching parts are available from PATC Transmissions.  You'll need to call them to determine what you have and what you'll need.

https://transmissioncenter.net/shop/ratio-adapter-other-ratios-available-call-jim-1-888-2012066/

[David A Young]

This unit runs on 12V if they are electric then they may have what I need.