Spedometer Not Working/ ABS light on

[tylerf350]

Spedo working intermittently and abs light on.

Hello to all. I have a 2000 F350 (7.3L Diesel) 4x4 Crew Long. I think that is all the data you need about the truck. I purchased the truck about 3 weeks ago and have put 3000 miles on it already. It has been running well. Today after I hooked my dump trailer to it (it was empty) I was on the free way and my ABS light came on. After that (approximately 20 miles) the speedometer began to act up. It would fall from 70 to 60 and quickly go back to 70... then when I got off of the free way it stopped working at all under about 30. At 30 it kicks on and seems to work at times... but it is shaky.

If you have any ideas for me please let me know. Thanks so much for all of your help. I have already done a few repairs thanks to this forum. I figured out my way through the "sluggish locks fixed with aluminum foil" fix so I hopefully can get some help with this speedo/abs problem.

Tyler

 

[DaveBen]

Your speed sensor is gone. It is located on top of the rear end housing and has a two wire connector attached to it. Get an new one and remove and replace the sensor.

Dave

 

[tylerf350]

thanks

I will change it tomorrow. Thanks. I was just doing some more reading and I read that somewhere else. Any Idea if the Ford one is any better than something from AutoZone or a place like that?

 

[Frankenstien]

I think the ford one is the same as auto Zones, they are both made by Beldon. When you take the Sensor out, there may be a large amount of metal debris built up on it (the switch is magnetic) sometimes, just cleaning the sensor will cure the problem.

 

[tylerf350]

Fixed

Thanks to all of you folks and a bit of reading on my part the truck is fixed. Here is what I found. Autozone will tell you that the part is not yet available if you ask for the Vehicle Speed Sensor. If you ask for the ABS sensor they will supply you with the "abs sensor in the rear diff". This is the part you need. The duralast box says speed control, and I don't currently have the part number (a buddy took the box). The best idea is to take the part off and take it with you to get the new part. ALSO, the bolt to get the switch out is in a bit of a tough spot to get to. I read somewhere that it was a 10mm but it is actually a 3/8".
Thanks for all your help.

 

[DaveBen]

Glad that fixed it.

Dave

 

[A/Ox4]

Wish I had seen this before. Coulda saved you a lot of time. The sensor on the top of the rear diff is the abs and speedo sensor.

A buddy of mine broke his off while off roading. He told me his speedo stopped working, and I told him to look under there. Yupp. Broken off. Glad it's fixed.

 

[leadfootlouie]

so this is great. I have the exact prob, no speedo and abs light on. did replace sensor on advice from friend/mech, but prob did not go away. However on rainy conditions the speedo seems to want to work. Any theories on grounding issues or shorting or anything like that?

 

[JRNOLL]

If you are getting some sort of a reading when wet you may have an open in a connector or a rub in the line going from the sensor. It only makes a circuit when water completes the circuit. Just a guess. Hope this helps. Joe

 

[leadfootlouie]

That was my guess. Prob have to trace wire back and see if any breaks or open insulation on wire.