Speedometer questions 91 (1 Viewer)

[leonard_nemoy]

I got in my 91 today and after driving for a couple miles my rig developed a crazy noise coming from the instrument cluster. At first my speedo needle pegged all the way to the right but the odometer seemed to work just fine. After sitting all day I drove it home and there was still a noise coming from the instrument cluster although the noise was much quieter. Driving it the second time the speedometer needle moved up and down as I accelerated and decelerated but the needle was very jumpy, also the odometer seemed just fine on the 2nd drive home. I am guessing something went wrong with my speedometer cable but it must still be attached because the needle is still responding. I am not sure what to do next because I am unfamiliar with instrument panels and speedometers in general.

I am wondering if there are separate cables for the speedometer and odometer? Or, are the speedometer and odometer operated with one cable and a series of gears in the cluster? It seems to me like if my speedometer cable broke or came loose than the speedometer amd or odometer should have stopped working completely, but they still seem to work. I tried digging up diagrams for it and found the speedometer cable but I could not find anything that actually showed what drives the odometer.
Any input is appreciated. Thanks

 

[Tools R Us]

One cable runs both. With age, the grease gives up, causing them to bind, make noise, etc. The cable can be pulled out of the sheath, cleaned and greased, is pretty easy and sometimes brings joy.

 

[leonard_nemoy]

One cable runs both. With age, the grease gives up, causing them to bind, make noise, etc. The cable can be pulled out of the sheath, cleaned and greased, is pretty easy and sometimes brings joy.

Can I remove the cable from the sheath at the transfer case, or do I have to get access to the back of the speedometer? Also I have a tool for lubricating motorcycle and bike cables that clamps onto the cable and allows you to spray lube into the sheath. Would this method work? Thanks again. I love the quick responses on this forum

 

[Tools R Us]

Pulls out from the transfer end. I wouldn't use that tool, can't tell how much is being added and don't want any of it in the speedo head.

 

[leonard_nemoy]

Awesome, thanks again. I hope this works because I am on a budget and I dont want to tear into the dash.... yet

 

[leonard_nemoy]

One cable runs both. With age, the grease gives up, causing them to bind, make noise, etc. The cable can be pulled out of the sheath, cleaned and greased, is pretty easy and sometimes brings joy.

So I pulled my speedometer cable from the sheath to clean and lubricate it. The cable seemed to be in great condition other than being filthy. I went ahead and cleaned it really well than gave it a generous application of white lithium. When I went to reinstall the cable, it was very difficult to feed it back all the way to the speedometer but I was able to get it back in. I ended up pulling the cable, cleaning it, and re lubricating it 3 times before I tightened everything back up for a test drive. Initially the speedometer still made a crazy grinding noise and didn't work on my first test drive to work. Driving home from work the noise went away and the speedometer started to work properly. Everything seemed better for a few days, but last night when I drove home from work the crazy grinding noise and malfunctioning speedometer returned. What should I do next? should I replace the actual speedometer, or try a new speedometer cable and or cable housing? Thanks again for all the help.

 

[Tools R Us]

Speedo cables wear out, cleaning/lubing helps, extends life, but wont work miracles. The view across the web isn't great, so just guessing.

 

[jonheld]

Late to this thread.
I had the same issue on my 91 some years ago. The speedo cable would make a horrible sound behind the dash when cold. I removed the inner and lubed it several times, until it finally bound up on the highway one day and ripped through the outer jacket. It made quite a mess.
Replace the cable with new. It's a little tricky getting behind the dash, but persistence pays off.

 

[bcomnes]

Late to this thread.
I had the same issue on my 91 some years ago. The speedo cable would make a horrible sound behind the dash when cold. I removed the inner and lubed it several times, until it finally bound up on the highway one day and ripped through the outer jacket. It made quite a mess.
Replace the cable with new. It's a little tricky getting behind the dash, but persistence pays off.

Are they still available to buy?

 

[marcus550]

Are they still available to buy?

My 1991 FJ80 also made a horrendous noise behind the speedo at around 145k miles. I disconnected the cable at the transfer case until I could get a replacement from Australia. It was obviously for a RHD TLC but it worked fine. I pulled apart the old one expecting it to be frayed or broken but it looked fine. Noise went away for about 3k miles and recently came back as a whirring/whining noise. Pushing/pulling on the cable under the dash will change the serpentine path of the cable slightly. This improved the noise, but I can still occasionally hear it at slow speeds.

I just replaced my 150k speedo with a 130k used one in an attempt to eliminate the noise. No change. Expensive experiment for no gain.

Getting the gauge cluster out isn't that difficult. Several big, fragile dashboard pieces have to come out first. For me, unplugging all of the connectors is the most difficult part. If you do, I suggest replacing all of your gauge cluster light bulbs while you're in there. A week after changing the speedo cable, the 'D' in my gauge cluster burned out.

 

[leonard_nemoy]

Are they still available to buy?

My 1991 FJ80 also made a horrendous noise behind the speedo at around 145k miles. I disconnected the cable at the transfer case until I could get a replacement from Australia. It was obviously for a RHD TLC but it worked fine. I pulled apart the old one expecting it to be frayed or broken but it looked fine. Noise went away for about 3k miles and recently came back as a whirring/whining noise. Pushing/pulling on the cable under the dash will change the serpentine path of the cable slightly. This improved the noise, but I can still occasionally hear it at slow speeds.

I just replaced my 150k speedo with a 130k used one in an attempt to eliminate the noise. No change. Expensive experiment for no gain.

Getting the gauge cluster out isn't that difficult. Several big, fragile dashboard pieces have to come out first. For me, unplugging all of the connectors is the most difficult part. If you do, I suggest replacing all of your gauge cluster light bulbs while you're in there. A week after changing the speedo cable, the 'D' in my gauge cluster burned out.

The issue is the cable housing itself, not the cable. If you can get the housing off the truck spray a few cans of carb and brake cleaner through it from the odometer side to clean out all the old degraded grease and accumulated dirt. Keep spraying until all the black stuff comes out. Next re-grease the housing and cable with new lubricant and re-install. This is why it will act up in the cold, all the old worn out grease and grime keep the cable from spinning and the cable binds up.

Goodluck.