88-90 Instrument Cluster A/T & M/T Differences?

[WeirdTim]

Hello, beside the gear selector window, are there any other differences in instrument clusters? My speedometer works most of the time but sometimes it doesn't. When it doesn't I smack the top of the dash and it starts working again. It's tough to find a M/T instrument cluster for my 1990 C1500, so I though I could use parts from a A/T to repair it.

Thoughts please?

 

[Loydw]

clean the contacts on the back of cluster. your "repair" moves the contection. good luck

 

[someotherguy]

Could also be there are cold (bad/cracked) solder joints inside the cluster. If you're good with a soldering iron you could fix it...if you're not, maybe farm that work out.

The automatic and manual clusters are the same other than the shift indicator panel which swaps right out easily.

The difference from one cluster to another will be the speedometer calibration, which is done inside the cluster on 88-91. It's a row of very low amp microfuses that are blown at the factory to represent a particular configuration of on/off hardwired switches depending on the axle ratio and tire size. So any cluster you get may or may not (most likely not) be the same calibration, and you'll end up having to re-do it. It's easy to solder a DIP switch in there and then use a meter to test the old cluster's configuration, though. Again, if you're good with a soldering iron..

Richard

 

[Ilija Kovacevic]

Hello, beside the gear selector window, are there any other differences in instrument clusters? My speedometer works most of the time but sometimes it doesn't. When it doesn't I smack the top of the dash and it starts working again. It's tough to find a M/T instrument cluster for my 1990 C1500, so I though I could use parts from a A/T to repair it.

Thoughts please?

There is a difference because I just got 2 that we're out of automatic transmission trucks and mine is a manual and when I put into the automatic clusters the truck wouldn't start