[Jordi]

I am from Spain, so first of all sorry for my english. I have a blazer 6.2 diesel year 85 and when running with a fixed speed the speedometer needle jumps and not stay quiet on the speed value. For example if I am running on a speed of 45 miles the needle goes from 50 miles to 40, and then goes up the 55 and down to 30, I mean this is not always the same average of fluctuation. And this is not always some moments, it depends on the speed the needle stays quiet on the right value and some other times jumps as mentioned. Could somebody give me a hand and let me know please which is the problem and the possible solution???
Thanks

 

[wyldman]

Welcome to the site Jordi.

Sounds like you have a dry or bad speedo cable.You can pull the inner cable out,and lubricate it to see if it helps.

If it's still bad,then you may have to replace the cable.Pay close attention to the cable rounting,as any tight bends or kinks will cause the bouncing speedo needle,and early cable failure.