Hey all, for a while I've been having a spot of trouble with my speedometer. For a while, when it was cold in the morning, it would bounce around from 10-30 mph, and would just bounce higher if I went faster. It would work fine after it started to warm up for whatever reason. Now, it is almost always doing it except at freeway speeds, but even then I don't really know how accurate it is. Also, sometimes when cold, it makes a horrible noise, like a shrieking, hard to describe. Here is a short video of what it is doing:


My question is, I feel like could have something to do with the speedo cable, ie it being loose or going bad. I was hoping, however, someone may be able to shed a little insight on what it may be before I go tearing my dash apart...

Thanks,

Jake

 

I would lube your speedo cable before it breaks. I am guessing it is binding near the top. What happens is it binds and the lower part loads up like a spring and then the bind releases and then spins fast to catch up.

I dont know the easiest way to do this, but it might be pull the cable off the back of the speedo and off of the transmission and force the lube up the cable from the bottom. I think you can reach the cable from behind the dash but the last time I did this was 1986 and I don't remember the particulars. The other possibility is the speedo itself is at fault but a binding cable looks like your video.

Good luck!

 

You need to get some graphite powder inside the cable. Preferably from the top down.

 

In the 84/85, you can get to the cable by reaching up under the dash in the driver's side and threading your arm through the harnesses etc.

The speedo cable pulls straight back.

 

Ive always used wheel bearing grease. It was actually recommended by the manufacturer of my Mercedes-Benz speedo cable.

 

NEVER use graphite on a speedo cable. It destroys the speedo bearings. I managed a speedo shop in an earlier life and I cannot tell you how much business graphite provided for us.

I think the speedo cable pulls out of the housing from the botton on asian cars. use a light grease only

 

. 2nd that. I've got wheel bearing grease from 93 that I still use

 

Funny. Being as graphite is the #1 recommended lubricant for cables in general. I see just as many problems occurring from using grease. Ever see grease turn to a solid?

 

It's a hard thing to get out of the back of the cluster, or so I thought.

Yeah, just grease it up and you should be ok!

 

Yes - white lithium grease would cake up. We used mobile one synthetic grease or a thin petroleum based grease. Never had any issues with grease both on in shop repairs and the custom cable/housing assemblies we built. These custom speedometer/tachometer drives ranged in length from a 6 inches to 15 feet.

I realize that graphite is the recommended lubricant but it in reality it was offered to the public because it was easy to squirt in the cable housing by a DIY. The effect on a perfectly good speedometer was similar to apply valve grinding compound and eventually it would destroy the lower brass bushings. Like I said, the business I managed made allot of money off of Graphite.

When do this service you want to remove the cable from the housing so that grease can be applied to the entire length of the cable.

The more I think about this, I believe that the cable comes out from the bottom and not the top so no need to disconnect the speedometer housing from the speedometer. It is easy to check this. Disconnect the speedometer cable housing from the trans and pull on the cable. If it comes out from the bottom it will slide right out.