why is my Speedometer is OFF by 20 MPH!!!!!!!!!!!!!

[wkumale]

Please help i have a 96 ranger 2.3 liter 5 speed. I just bought it and so i dont know the history.. The speedometer says 90 and the GPS says 72... the speedometer says 50 and the GPS says 36.... It seems the faster i go the more its off.

I checked the tire sizes first. It has 195/70/R14 these look small but i was told these are what stock for the 2wd.

Then i was told to try to replaced the Speed sensor.. I was told there are 2. One on the tranny and one on the rear. I was told to replace the one on the tranny. I did and there was no change. I searched a lot of threads and the rear sensor seems to only get replaced when the speedometer stops working altogether. What is my next step? anyone....

[FishFind]

What are the rpm at when this is going on>>
Do you think the tranny is slipping.

I would guess speedo wither on dash or on tranny.

[mmerlinn]

Your tire size looks correct, but you can check them against the size noted on the VIN plate on the driver's door or driver's door support.

Even if the tire sizes are incorrect, there is no way your speedometer could be that far off just because of the tires.

The rear end ratio could have been changed by a previous owner. You may need to call the dealer to find out the correct ratio for your truck then check that info against the tag on your rear end.

Other than that, the only possibility would be something broken in the speedometer chain, like sensor or speedometer head.

[taglicious]

I just purchased a ranger with the same characteristics. When it's warmer out I'll check it out and see what the problem is. Mine, as it stands, is at the 15 mph marker. I'll post up as soon as I figure out what the problem is.

[timd]

Ever figure this out?

[taglicious]

Originally Posted by taglicious

I just purchased a ranger with the same characteristics. When it's warmer out I'll check it out and see what the problem is. Mine, as it stands, is at the 15 mph marker. I'll post up as soon as I figure out what the problem is.

i forgot to ask... what does your gauge say when it's parked? Mine actually says 15 mph.

[65comet]

Could be someone took the speedometer apart to mess with the odometer and roll back the miles. When they put it back together they didn't push the speed arm indicator back in to the correct position.