speedo doesn't always work 2006 f350

Speedometer in 2006 F350 diesel; it used to be that only when it was real cold outside, the speedo would quit working. Now it seems to be doing it more often. Is this a common problem? Is there a simple fix for it?

Thanks
Mike

not a mechanic, does it shift funny when the speedo quits working?....does this truck have a speed sensor on the rear housing?

On my 99 it was a speed sensor on top of the rearend housing. Not expensive and easy to change.

72puller wrote:On my 99 it was a speed sensor on top of the rearend housing. Not expensive and easy to change.

X2, my 97 was like that.Like said,it shifted funny also.

I dont think the speedo reads only off the VSS anymore, I know the sensor can fail and the speedo and tranny work fine, it will set a code though....p0500.

I don't work on that end of the truck much I can ask the EEC guy when I get back to work.

I didn't realize there was a speed sensor there, well thats cool now I know why my bro's truck was acting up.

bb429power wrote:I didn't realize there was a speed sensor there, well thats cool now I know why my bro's truck was acting up.

they started putting them in the rear early....still in the 80's. maybe 87 or so.
not all of them ran the speedo off of the VSS in the rear though..just ABS for a while as the Speedo sensor was still in the trans or transfer case up until the early 90's

Yeah, my VSS in the rear is setting an ABS code because I have some metal in the housing and the magnet picks it up.

The truck runs fine, shifts fine, there are no problems there. Sometimes the speedo does not go back to zero when stopping, and it says you are running 80 when really running 50. Other times it does not go up at all, or shows you are running 30 when running 70. No lights or codes flash in the dash, the only code I have seen is a TBC Fault. I was told this is in the trailer brake controller, probably corrosion. Most of the time it is fine, just every now and then it acts up. Those intermittent problems are a bear to find.

Almost sounds like you parked next to a GM truck and the "cluster cooties" migrated over to your truck.

Brian

We have seen this in some of our 2010 f-150's.
It's a cluster deal... when you go over bumps, or hit the cluster will it change?

No, Nothing really seems to change it. If you come to a complete stop it normally picks back up and works. Sometimes you have to shut the truck off and restart it before it will start to work. When it first started acting up, it was like the needle would get stuck and only go down to 30mph. Once it stuck, it would not go back to 0 until you shut it off. It doesn't do it all the time either. Originally it started doing it when it was really cold outside, single digits, but now there is no rhyme or reason. It may work fine for a month or 2 and then out of the blue just acts up again. I don't drive the truck that much, maybe a couple times a week, it only has 48000 miles on it.

Read this.

http://www.ford-trucks.com/forums/1041063-speedometer-problem.html