Epic91GT

ok my speedo gauge on my 91 GT never tells me an exact speed it is always jumping around, so to fix it i need to know if the speedo is electronic or does it use a cable

mcginnt

its a cable. like 20 from vatozone i think... if you mean it jumps from like 0-30 i think thats normal... mustangs are used to going fast not slow... thats my explination for that happening lol...

Epic91GT

nah when im doing like 45mph it says imdoing like 80-140mph

mcginnt

do you have the right speedo for your gears?

Epic91GT

yeh everything is stock in the car

worm2500

i had the same problem, people told me it was the speedo head. so i just bought a whole new cluster off ebay with white faced guages. it cleared up the problem. but i was out 100 bucks. you might try taking it apart and cleaning the magnets

Epic91GT

ne other ideas if it isnt the magnet, how much does a new cable cost cuz i dont wanna spend to much at the moment

LesteR723

lol did you go faster than the speedo can show? my friend has a 87 GT and did that and his jumps too

Epic91GT

no like i said in the above post i would b doing like 40 and the speedo would b jumping from 80-140 andeven if i stop at a light it says im doing 40, it varies each time so is there any explanation as to why is it doing that or is the cable just need to b replace

Monstang

The cable will not cause it to stay on 40 at a stop light. That is the speedo head. But, the cable will cause the speedo head to go bad. I have replaced a speedo cable, not bad at all. You can get them at 50resto.com
Mark