g741.org

Hey Gang...

Me again...My speedo is also not working. I pulled the guage cluster out and found the big speedo tube was attached, and found that it is also attached to the transfer case, but it no work....any suggestions? Guage or line?

Ty

I'd start with the cable, then the speedometer, then the drive gear on the transfer case.
Gary

I am sure Gary does not mean you should go out and buy those items one at a time in that order!

Unscrew the sheath (Tube) at the rear of your speedo. Grasp the inner cable and see if it will turn with very light pressure. If it does the cable is broken. If it doesn't then grasp the inner cable and pull it out of the tube about 1". Spin it with your fingers. Does it spin freely? Yes is good sign. Then slide it all the way out. Is it lubed or dry? If lube looks clean and fresh leave it if dry or ugly clean it in solvent and lube sparingly with a tube of speedo cable lube.

Now with your finger tips spin the tip of the speedo's input shaft which is a very short stub. Spin it CCW and you should see the speedo needle rise in speed. You can also chuck a short piece of old speedo cable in a drill and do this. A small finishing nail will also work. If the speedo needle won't rise or is very jerky then you have a speedo issue. Try a light oiling of the speedo input shaft. Then try the drill again.

No, I had to get back to work so I shot a quick post! My intention was to say to troubleshoot those items in that order. Thanks for squaring me away Cuz!
Gary

Tyroma wrote:Hey Gang...

Me again...My speedo is also not working.

Not to worry! Chances of your getting a speeding ticket are pretty slim in an M37.

Actually, though, it shouldn[t be hard to fix. The guys have pretty well explained it. Enjoy getting your hands dirty.

Lifer,
I got a demo drive in a M37 yesterday that could easily get a speeding ticket!

Nice! That would be the one with a 318 under the hood? Whatever powerplant it had, I sure hope it had a working speedo!

360

Wow! A 360 is even better. Hope it had Ugly Truckling's 4-wheel disc conversion installed for extra "whoa" power.

Yep

Unscrew the sheath (Tube) at the rear of your speedo. Grasp the inner cable and see if it will turn with very light pressure. If it does the cable is broken. If it doesn't then grasp the inner cable and pull it out of the tube about 1". Spin it with your fingers. Does it spin freely? Yes is good sign. Then slide it all the way out. Is it lubed or dry? If lube looks clean and fresh leave it if dry or ugly clean it in solvent and lube sparingly with a tube of speedo cable lube.

[b]Did that...it does not turn while fully inserted in the speedo tube. Pulled it out about 1", it did spin. Pulled it out a bit, appears quite lubed.[/b]

Now with your finger tips spin the tip of the speedo's input shaft which is a very short stub. Spin it CCW and you should see the speedo needle rise in speed. You can also chuck a short piece of old speedo cable in a drill and do this. A small finishing nail will also work. If the speedo needle won't rise or is very jerky then you have a speedo issue. Try a light oiling of the speedo input shaft. Then try the drill again.

[b]Spun the speedo stub with my fingers...it moved the needle. I figured that maybe the little tip wasn't in the speedo far enough...tightened it all back up, went for a drive...still doesn't work.[/b]

[b]What's next?[/b]

Drive it with the speedo cable disconnected and see if the speedo inner cable actually turns.

[quote="cuz"]Drive it with the speedo cable disconnected and see if the speedo inner cable actually turns.[/quote]

Tried that....IT'S FIXED!!!! I pulled the cable out uner the dash, and went for a drive. The pin wasn't spinning, so I figured "okay, the cable is broken...I cna fix that" Then I thought to myself "maybe the pin at the other end isn't meshing with the gear on the other end" so I pushed on the pin while rolling, and CLICK it popped in and started spinning! I hooked it back up to the guage and it jumped to life!

So...now I know that 45mph is right around where my truck like to cruise at. How fast do you guys run your trucks? I know that there were rod issues when these truck got over-revved. Anyone use a tach? Can you get a 24V tach?

Thanks for the help!

Ty