Intermittent Speedometer

[centurion95]

My '01 Friendship has a weird issue. Intermittently the speedo will jump 5 mph or so while driving. I brought the rig to a Allison shop and they could not figure it out. I cleaned all of the connecters on the tranny ECM and the Cummins ECM as well. On this venture it happened and I discovered that if the rig is shut off and then back on, the problem goes away until next time.

Has anyone had this same issue?

[RayChez1]

On, I have not had that problem, but it sounds like it might be on your ignition switch. Since you mention that if you turn it off and then restart it will not do it again. Maybe a lose connection.

[03heritagerider]

I had this problem. I couldn't figure what was happening. I then noticed that the mileage was WAY OFF! Our trip to Florida should have registered about 1200 miles, but it was showing 1900 miles. When I switched to the trip meter, I measured against the mile markers on the interstate. I saw that for about every 5 miles I traveled, it registered 8 on the odometer. I replaced the spedo/odometer (it was still under warranty then), but it did the same thing. I took it to the Freightliner dealer and they discovered (and had no explanation why) that somehow it had switched to Kilometers. I think it was something in the ECM or computer. They reset it and all is fine now.

[RayHarkness]

not sure if this helps or not..or you have resolved your issue. Speedometer and gauges are run thru the VDC Vehicle Data Center. This box on our 2002 gulfstream is located on passenger side, adjacent to the engine. It has two 1/8" plastic lines coming from engine and to this square box. There is another box which is the Allison.
I had speedomete on and off problems, and then a rear air pressure gauges go bad. I replaced the Rear Air Pressure gauge, all was well for a bit..then it started pegging or dropping, and setting off the alarm. (note Speedometer was intermittent on occassions)

I contacted Freighliner, thru their online site, to ask questions. I provided my Frt VIN Number. They immediately knew my issues was this VDC box. There was a replacement VDC available. Apparently for several years, 2001 thru 2002, they had issues with bad soldering. They changed manufacturers..and resolved the issue.
My thinking is, you could have this issue. They can IMMEDIATELY tell you if your in that group that was bad.

A Freightliner dealer in Orlando ALSO told me there was a recall on Dashboard, Gauge wiring harnesses., Freightliner verified I was NOT in that recall.

but..they verified I did have the bad VDC ..I got a new one from Freightliner..of course out of warranty ...cost me over 400 bucks. I heard many were trying to resolder connection..I was not that brave..I fear breaking down.


not sure if this helps..but you can always run questions by Freightliner, their online people..just make sure you have your vin. They are VERY cooperative.