Speedometer not working but Odometer functions fine (1 Viewer)

[Tiamat]

Hi everyone,

First off, thank you everyone for the information on these forums. Pretty sure without this site I wouldn’t be able to keep my truck running.

My question is this: I have a 1989 FJ62. The Odometer functions fine (I’ve measured against known distance, given the 33” tires its within acceptable range). The speedometer however, does not. It will show rapid acceleration and max out the needle by the time I’m doing roughly 15MPH. it will intermittently work, but rarely.

Ive searched the fourms and haven’t seen this issue, it’s always both non-op. Would this indicate that the speedometer housing itself is the issue and not the speedometer cable? Visual inspection of the cable doesn’t seem to show any issues.

Curious to hear everyone’s thoughts. Thanks!

(since I know everyone likes photos, I’ve included one from Lucerne Valley)

 

[onemanarmy]

Have you replaced the cable? Does the needle stay at 15mph? Does it bounce?

 

[OSS]

Start looking for a functional used speedometer. Its not a cable issue because the odometer works fine.

sor.com has a used one for sale $485

Enter the part number in their search field:

180-03L-U

 

[Tiamat]

Have you replaced the cable? Does the needle stay at 15mph? Does it bounce?

Cable hasn’t been replaced to my knowledge, although I’d have to double check. No bouncing on the speedometer needle, it just will max out the speed super fast.

Start looking for a functional used speedometer. Its not a cable issue because the odometer works fine.

sor.com has a used one for sale $485

Enter the part number in their search field:

​

180-03L-U

This is what I was thinking as well. So the cable itself does control the odometer output correct? I haven’t actually torn the housing down, but I would assume a single input gear from the cable is spinning 2 gears (one for each function?)

It looks like Cruiserparts.net also has them for much cheaper, I’ve seen some on eBay around $100~$150ish as well.

 

[3_puppies]

lots of good used ones out there and alot less than the above price

you might even find one close to your current mileage

 

[OSS]

Yea its a very simple (old fashioned) device. The spinning cable plugs into the back of the speedometer and it turns gears. One set for the speed and another for the odometer.

 

[FJ60Seth]

If you’re not a purist, Speedhut makes a GPS speedometer that looks excellent in the stock dash location. Costs $300 + $70 for a set of adapter brackets from Trail Tailer. I had a speedometer rebuilt, by North Hollywood Speedometer, for an old Mercedes. Cost was $325.

 

[Godwin]

My question is this: I have a 1989 FJ62. The Odometer functions fine (I’ve measured against known distance, given the 33” tires its within acceptable range). The speedometer however, does not. It will show rapid acceleration and max out the needle by the time I’m doing roughly 15MPH. it will intermittently work, but rarely.

Ive searched the fourms and haven’t seen this issue, it’s always both non-op. Would this indicate that the speedometer housing itself is the issue and not the speedometer cable? Visual inspection of the cable doesn’t seem to show any issues.

Since your odometer functions fine the cable is not the issue. The speedometer needle is turned by magnetic force, there is no physical contact between the cable and the speedometer. I dissembled a speedometer last year and found that the cable spins a magnet that sits inside a bell that's connected that the needle is connected to. Contamination within this bell will alter the needle function and contamination comes from gear oil migrating up the speedo cable housing. The speedometer is easy to dissemble and clean.

 

[Michael Hanson]

Hi, Clean and lube cable itself on the inside of sleeve. I bet it’s worse when it’s cold outside.

 

[Tiamat]

If you’re not a purist, Speedhut makes a GPS speedometer that looks excellent in the stock dash location. Costs $300 + $70 for a set of adapter brackets from Trail Tailer. I had a speedometer rebuilt, by North Hollywood Speedometer, for an old Mercedes. Cost was $325.

These two are both interesting thoughts. I thought about the speedup Complete setup, but not about just replacing the speedometer portion. I didnt think of finding a rebuilder either.

Since your odometer functions fine the cable is not the issue. The speedometer needle is turned by magnetic force, there is no physical contact between the cable and the speedometer. I dissembled a speedometer last year and found that the cable spins a magnet that sits inside a bell that's connected that the needle is connected to. Contamination within this bell will alter the needle function and contamination comes from gear oil migrating up the speedo cable housing. The speedometer is easy to dissemble and clean.

I assumed it would be a gear, but based off this I will probably end up pulling and inspecting to see if I can clean it out. There had previously been a lot of gear oil migration that I had fixed when I resealed the transfer case.

 

[Tiamat]

Just wanted to provide an update, cleaning the speedometer gauge fixed the issue. I used a can of WD-40 electrical contact cleaner because it's pressurized but also not a harsh chemical like some other aerosol cans. Not my photo, but the area I highlighted is where I sprayed to clean out most of the oil, there was enough oil to be visible within the actual housing itself. You can see how the speedometer works by moving the smaller bell piece within and watching the needle move, letting loose will reset it to 0. I recommend anyone else who has this same issue make sure that the gear cable is properly sealed at the transfer case to avoid the oil going back up and creating this issue again.

I have no basis of comparison, but the gauge definitely is not "responsive" in any sort of way. It kind of drifts with the acceleration and deceleration, and there's a lag between moving from a stop and it starting to register, but other than that it is fully functional and given the tire size within the proper margin of error. The speedometer normally reads about 5MPH to 7.5MPH under what a GPS one shows. I have no need for an ultra precise one anyways, so this is more than satisfactory.