BROKEN GAUGE CLUSTER

[Tony_jr_LGND]

Yup, my dads 84 Chevy K5 Blazer that he is going to pass down to me has had a broken gauge cluster since around '99, what happens is the speedometer needle bounces up and down constantly instead of functioning properly, anybody know why? my dad said something about wiring but i need another persons opinion.

[LowandLoud]

I would replace the speedometer cable.

LL

[wooferdog]

Does it have cruise control ? If it does it will have a servo on the driver side fender that the cable goes to from the transmission then another cable to the speedo that might have a bad gear in it. But check the cables first. It sounds to me like it's the speedo itself as that was a problem with the older cable driven speedo's.

[Tony_jr_LGND]

Does it have cruise control ? If it does it will have a servo on the driver side fender that the cable goes to from the transmission then another cable to the speedo that might have a bad gear in it. But check the cables first. It sounds to me like it's the speedo itself as that was a problem with the older cable driven speedo's.

I only got to drive it a few times and i never use cruise control but more than not it should be there

[wooferdog]

You can take the cable off that goes to the speedo and connect it to a drill motor. Start it on a slow speed,drill will have to run in reverse and have someone watch it as you speed the drill up and see what it does. If the speedo is still jumping that will tell you the speedo is bad and rule out the other parts.

[Tony_jr_LGND]

You can take the cable off that goes to the speedo and connect it to a drill motor. Start it on a slow speed,drill will have to run in reverse and have someone watch it as you speed the drill up and see what it does. If the speedo is still jumping that will tell you the speedo is bad and rule out the other parts.

being that its been like this for 13 years you think i might as well go and buy a new gauge

[LowandLoud]

being that its been like this for 13 years you think i might as well go and buy a new gauge

Thats all fine but if it turns out you're gauge is good and the cable or gear is bad, you will be no further ahead. Better off to diagnose and zero in on the actual cause of the problem.

LL