so the other day i noticed my speedo is off... or at least it feels like it is. ill be going 10 mph and itll say im going faster. any ideas what the cause is and how to fix it?

 

Reading too fast and steady? Or reading too fast and bouncing/erratic?

Also, cable driven or electric speedometer? I can't remember the change point....might have been as early as '82.

Cheers
DD

 

it reads fast but steady... ill drive it around tomorrow and double check. and im not sure if its electric or cable. how would i find that out?

 

also off topic but what kind of tranny fluid does this beast take?

 

Take a look at the tiny fine print on the speedo face. If it says "Smiths" it is probably cable. If "Veglia", probably electric. "Probably". :-)

Best to simply take a look at the back of the speedo and see if there a cable, or merely wires, attached.

Or look at the right side of the transmission for same.

Fast but steady reading? My guess is that somebody changed the differential final drive ratio. Or installed tires that are significantly smaller circumference.

Cheers
DD

 

"Type F" or "Type FA"


Some use Dexron with good result but F or FA is the correct stuff.

Cheers
DD

 

ok ill check it out tomorrow

 

A couple of ways to verify speedo readings of any kind.

1. Some roads have/had mile markers. Set speed by throttle at 60. It should take a minute to get to the next marker.

2. There is a way to compute MPH from RPM via gear ratio and tire rolling circumgerence, radius or diameter. Sorry, I am not sure where mine are.

3. Some communities have radar warning trailers. They depict mph in big lights.

4. Have a mate drive at a steady sixty. See if your car matches, exceeds or falls behind. Note your speedo reading for the relation.

Carl

 

it is an electric speedo..and it does hold steady. it just feels like the car is moving slower than the speedo

 

I don't know if it works for electronic speedos but I know some shops can calibrate a speedometer to make it read properly. May be hard to find as I only know of 1 place in my entire City that does it but maybe you could call around or search the web to see if somebody in your area does this and whether or not it works on electric ones. Someone I know even got off a speeding ticket by claiming their speedometer was off, paying that place to re-calibrate it, and bringing the receipt to court.