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What can i check to get it functioning again?

I just did a gear oil change all around and noticed that the rear differential drain plug was a little loose so I may have lost some oil.

Anyway, the speedo has worked just fine always and the only thing that has happened recently is this gear oil service.

Wisdom from the forum will be greatly appreciated!

If I don't know how fast I'm driving, you guys don't want me getting a speeding ticket now do you?

If it were me, I'd unscrew the speedo cable where it enters the speedo. It's probably got the 90 degree angle on it. Get the cable situated so you can view the central cable, then go for a drive and see if it's turning.

If it's turning, then you've got a defective speedo. Speedos can often be fixed.

If not, check for a bad cable. Unhook the cable at the bottom, and turn it. See if the cable turns up top, or is broken within. Cables can be replaced.

If the cable's good, then search for repair advice on the speedo drive. It's been covered pretty well in the past. I can't offer you much there, other than I don't think low oil will cause this. Certainly low oil in the rear diff cannot.


EDIT

Oh wait, I just noticed that this is in the Electrical forum. Do you have an electronic speedo? If so, where is the sender: hooked to the speedo cable? or hooked to the drive down below?

If you've got the original speedo, then this isn't an Electrical question, as it's a mechanical speedo.

Yeah, yeah, I'm a dumb $hit. I was thinking it was like a "normal" car and the speedo was an electrical item. I did consult with my Pinz "savant" in Prescott, AZ and he gave me the same advice.

The speed needle on the gauge spins freely so I actually disconnected the speedo cable at both end hoping it would spin freely and it doesn't. Lots of torque. I hope that means I have a bad cable, Thilo indicated that to repair the gear in the front differential was a time consuming ($) process.

So, it sounds like a bad speedo cable...right?

If the 90-degree gizmo is still connected to the cable, I'd remove it and check the cable again. I assume they can fail. Otherwise, it sounds like that cable is bad.

I removed my mechanical speedo cable and 90 degree worm gear last year when I put in the electronic.

Have it still, should someone need one.

Ed

ED,

Save that old mechanical stuff. I bought a VDO electronic speedo and it quit after 2000 mi. Just quit, flat out, quit working. I put the old one back in.

Morris

OK.
Thanks, Morris!

Thilo indicated that if this isn't the cable,the replacement process is hugely expensive. So there is the option of going electronic for a speed replacement if i need to go that route?

Has that been discussed here before?

I've installed the VDO electronic speedo in 2 Pinz's and both have worked out fine. However, I recall someone posting on the forum that their's quit after a while. It's a relatively easy install and is easily programmable. Road tests with a chase vehicle have shown them to be very accurate.
SAV carries them.

Paul C

Sounds like an easier fix than replacing the gear drive in the front differential.

I'll check SAV for details if it looks like that's my problem.

I'm going from sketchy memory here, so please, someone correct me if I'm wrong...

I believe that the drive for the speedo is located in the housing ahead of the front differential. Whether you use a mechanical or electronic speedo, they both require that drive to work. If the speedo drive is AFU, a new speedo won't cure it.

To repair it, you'll need to pull that housing out, which requires a bit of tear-down. But there just aren't that many parts in there. It can't be too bad.

First thing is to figure out if the drive still works.

Paul, you're absolutely correct. If there is something wrong with the speedo drive gear, etc., it makes no difference which speedo you are using because the cable or the sensor both need to engage properly.

Parts Group 03-15 shows all the pertinent parts.

Paul C

That all makes sense, unfortunately! I'll start with the cable replacement and if that doesn't fix it,I'll move along to replacing that drive off the front differential.

Thanks guys.

David

I installed a VDO speedometer several years ago. It worked great until just a couple of weeks ago when the odometer LCD display stopped working.

Does anyone have any idea on how to reset the unit to see if the odo comes back to life or am I looking at a new speedometer?

Thanks,