i just bought a 91 ranger a couple of weeks ago and the tach is not reading correct.at 65 mph in over drive the tach is reading 3100 rpm.is this a comon problem and is it easily fixed.

 

Search the web for a free program called "GearCalc." Use this program to determine engine rpm's by providing tire size, gear and rear axle ratios.

Remove the instrument panel lens cover and remove the needle on the tach. (You need to remove some dashboard panels to be able to access the lens.) Drive at a mid-range speed, e.g. 50 mph, and gently reinstall the tach needle at the proper rpm as determined by the GearCalc program.

You can do this by yourself, but it is difficult based on my experience. It would be easier to have two people do it - one driving the truck and the other inserting the needle.

Reinstall the instrument panel lens and the other dashboard parts and you should be all set.

I have recently done this and it worked for me. Good luck.

 

thanks but it works fine for about 5 min then goes all wonky.i'm thinking i need a new tach.