jumping speedometer

[94expo]

after some driving my speedometer will start bouncing a little. I get about a 5 mph bounce. If im going 65mph it will bounce up to 80mn and down around 60. this will only happen after drive a little distance. about 25 miles. It will clear up after a while. then at times come it will come back. is this system straight cable or is there electronics involved. The truck Does not feel like its speeding up or slowing down. Its a 94 XLT

 

[Alec]

Your 94 should just have a cable running from the tranny in a 2wd or tcase in a 4x4. Probably just need to unbind or lubricate the cable.

 

[Joey P]

I have the exact same problem. How Hard is this to fix?

 

[94expo]

Its a 2 wheel drive. I thought Lube also but it only happens after I drive for awhile. then it will clear up. Does the cable run from the tranny straight to the speedometer or does it go thought some other device prior to the speedometer.

 

[94expo]

this thing is equiped with a VSS (vehicle speed sensor) Its part of the cable housing on the side of the transmission. Has anyone had any experience with this or know its function and could it make your speedometer bounce

 

[Perry]

I have the same problem and I changed out the cable, and the gear in the transfer case and neither one helped.
I asked my mechanic friend and he said it is in the cluster itself but to have it fixed by Ford it is REALLY EXPENSIVE so I just use my GPS to check my mph.
The odometer works fine so I just got used to it jumping around.

 

[V8BoatBuilder]

I had an old Peugeot and the speedometer cable was routed by the exhuast - as the car ran, and the cable heated up, the speedometer would jump around. A new cable solved the problem temporarily, untill the heat got it again. I'm not sure the routing on the 1st gen Xs, but the intermittentness might be related to heat. FWIW.

 

[WEENIE666]

YEAH, I HAVE A 92 AND IT DOES THAT, I WILL BE GOIN 55 THEN SPEED UP.....NO MOVEMENT...SO I SPEED UP SOME MORE,THEN..*BAM* IT JUMPS UP TO 70!!!
I GOT PULLED OVER 2 WEEKS AGO FOR DOING 78 WHEN MY SPEEDOMETER SAID 65 ON CRUISE!!!!!
I HAD A FREIND FOLLOW, ON CELL PHONES TO TELL ME WHEN I HIT 70 MPH, SHE WAS DRIVING A BRAND NEW CAR SO ITS SPEEDOMETER WAS CORRECT. I WAS DOING 70 BUT MY SPEEDOMETER SAID 58!!!
THIS SUCKS, I THINK FORD SHOULD BE RESPONSIBLE!
THE OFFICER DIDNT WRITE ME A TICKET BECAUSE HE SAID HIS PARENTS HAVE A 94 & IT DOES THE EXACT SAME THING! I HAVE A 92, FORDS SUCK.

 

[outrun84]

Had a 91 with same thing

I had the problem of the wavy needle on mine too, ford says that is is a sending unit on the tranny but i duno, they lubed up the cable and everything but it did not fix it. I got a quote from them of somewhere in the $900-1000 range i thought it was &^*$%^& nuts so i said screw it. I would have the cable lubed and then from there i duno.

 

[94expo]

There is a small sending unit on the side of the trans where the cable comes out. Its called a speed senser that send speed info to the emissions. Im thinging it maybe interfering with cable movment causing the bouncing. Auto zone has them for 24 buck. that could be the only thing I could think of in the way of sending units on the trans. The rest if the system is direct gear.

 

[Shurup]

My speedo is actinng funny too, but in different way. In cold weather (-15 C to -30 C don't know how much in F) after I start driving it after it completelly cools down at night it shows me around 100 km/h instead of 60-70 km/h. The colder the weather, the worth it. Howewer it goes back to normal after I drive my truck for 10-15 minutes.
What can it be in my case? Thx.