I posted the following on 1/12 in (1968 full sized vans)and due to no feedback ,I posted again on 1/16 in ( Transmissions) part of the forum.

i just checked both today on 1/22 and theres been no response on either.
Both posts have a total of 184 views and still no answer.

For those of you that havent seen it earlier...here it is:

SPEEDOMETER GEAR
On earlier ATs 1960-77 I just followed the speedo cable to the enty point in the trans,un bolt,remove and replace.

I cant find my speedo gear on my 90 AT m4od. It must be electronic ?

If its electronic,is it a simple unbolt and pull it out/off,or does it envolve more?

 

Wish I could help you, but I have no clue. Are you sure that's the correct model designation? I thought "M" referred to a manual trans...

Here's a 4 speed auto ID chart:

 

Is there a speedometer cable? If so, find where it goes. If not, it is electronic. If it is electronic, no gear. In which case it is probably using a sensor in the rear diff pumpkin.

My '88 had a speedo cable and a gear. It was in the rear shaft housing. Had a spiral plastic gear on the shaft, and a spur gear on the cable. You couldn't miss the big speedo cable. So if you are not seeing it, I'm betting a '90 does not have one.

 

OH..typo. its a E4OD

 

[quote=bpounds;11325661]Is there a speedometer cable?

Nope,couldnt see one

If it is electronic, no gear. In which case it is probably using a sensor in the rear diff pumpkin.

Uh Oh....

 

Is your speedo not working? Or are you trying to adjust for big tires?

Look at the very top of the differential for a sensor. Should be easy to change.

If you want to adjust the speedo, you might have to look for an aftermarket programmer. Not sure what that would take.

 

Thanks for the location of the sensor: The speedo & odo just stopped working one day

 

I found another post on this site about it, here.
"For that vintage truck the speedo and RABS systems are seperate, the speedo is cable driven off the T-case and the rear axle sensor feeds the RABS system only. Somewhere around 1992 Ford integrated the two systems and did away with the cable driven speedos, you can tell what system a truck has by looking at the odometer, if it's mechanical then the dash is cable driven but if it's LCD it is electronically driven from the combo RABS/VSS sensor in the rear axle."

https://www.ford-trucks.com/forums/1...de-6-rabs.html