My 2001 F250 has just been acting up hard lately. The speedometer isn’t working, nor are the miles even clocking in. It is the analog dash. Also Iv got some problems with the Rpms. At any speed or gear it feels as if the trucks engine just stops and turns on and just jerks the whole truck, sometimes it’s once sometimes it’s 4 times maybe more. I thought maybe trans but I don’t see it doing that in every gear.

So to be more clear my speedo doesn’t display speed at all- Iv changed vss, and checked the gears in the speedometer both are fine.

Truck jerks/jumps bad in any gear- I don’t know if this has anything to do with the speedo not working. Haven’t dug deep into this not sure where to start.

Truck will display code p0320 ignition/distributor engine speed input circuit only every once in awhile.

Shes been a good truck, bought it 3 months ago with 53,000 from an ashphalt company, they did destroy it but I got it for 2k and put 2k into it and she’s almost like new.

New ball joints
new brakes/rotors calpiers
new front axle stubs and ujoints
drove shaft ujoints
tierod ends
shifting bushing
refurbished the frame
new tires
new hub assembley
new lock out hubs
new vss
new fuel filler
new tank pressure sensor
all new fluids in everything
Flatbeded

I have but haven’t put in
crank shaft position sensor
camshaft position sensor
soark plugs
ignition coils
Leveling kit
New cab corners
Shock absorbers

Not all this stuff needed replaced just went ahead and did it. Iv never encounters this problem before so any info would help

 

I've seen a few speed sensors on the diff go bad on these trucks. That affects Speedo and trans too. However if you have a crank sensor code... maybe two issues? Not common but two problems do occasionally happen at once.

 

 

 

The sensor on the differential is for the anti lock brake system. There may be more than one sensor on top of transmission. I am not familiar with the 4 speed auto. If there is more than one then you need to replace the rear sensor. If the pcm is not getting a good speed signal then weird shifting can and probably will happen.

 

 

 

There is so much bad information above!

There are two speed sensors on top of the transmission. Neither one feeds the speedometer or the odometer. The speed sensor on top of the rear diff does feed the ABS, but the speedo, odo, and the transmission all use this sensor, too.

 

If the rear ABS sensor fails, you'll loose the speedometer, odometer, the ABS light should be on, the speed control won't work, and the PCM won't be able to properly schedule shifting of the automatic transmission. If you do not have the full complement of symptoms, its probably not the sensor.

You can check the sensor for a gross failure with an ohmmeter. IIRC, a good one usually reads around 1300 ohms, give or take a bit. When they fail, they usually go open.

 

 

My SWAG* is that there is a problem with the connector to the VSS. If someone pushed a probe into the connector it could have spread the pins a bit so that they don't make good contact.



*SWAG =Silly Wild A Guess

 

Then there's probably nothing wrong with the sensor.

Check the VSS data in the PCM with a scan tool. If it's correct, then the cluster is the likely issue.