1991 GMT 400 odometer quit

[mcarlo86]

Does anyone know if there is someone who can repair a 91 GMT gauge cluster (diesel with tachometer)? The odometer in my cluster isn’t working, but all the other gauges work.

 

[bucket]

It doesn't work in my '90 either. I've repaired odometers in other GM speedos before, it was always a broken plastic spring clip. I was hoping my '90 cluster has the same issue, but I haven't opened it up yet.

'91 was still the half-moon style gauges, right?

 

[mcarlo86]

It doesn't work in my '90 either. I've repaired odometers in other GM speedos before, it was always a broken plastic spring clip. I was hoping my '90 cluster has the same issue, but I haven't opened it up yet.

'91 was still the half-moon style gauges, right?

So the pickup is a ‘90 K2500 6.2 diesel that originally came with the half moon gauges. I wanted a tach, so I found a ‘91 diesel tach cluster with the needle gauges. Had to re-pin since Chevy decided to change the pin out for the plug from ‘90 to 91. 92 and up have a totally different plug style. Anyway, I haven’t opened it up to look for a broken spring clip. Are those clips available?

 

[bucket]

So the pickup is a ‘90 K2500 6.2 diesel that originally came with the half moon gauges. I wanted a tach, so I found a ‘91 diesel tach cluster with the needle gauges. Had to re-pin since Chevy decided to change the pin out for the plug from ‘90 to 91. 92 and up have a totally different plug style. Anyway, I haven’t opened it up to look for a broken spring clip. Are those clips available?

In the case of the other ones I fixed, the numeral shaft was held in place by plastic spring tabs that were a part of the speedo assembly. If one of the little plastic tabs break off, the numeral shaft will no longer make contact with the drive gears. All I ever did was strategically place some stainless safety wire to retain the numeral shaft.

 

[mcarlo86]

In the case of the other ones I fixed, the numeral shaft was held in place by plastic spring tabs that were a part of the speedo assembly. If one of the little plastic tabs break off, the numeral shaft will no longer make contact with the drive gears. All I ever did was strategically place some stainless safety wire to retain the numeral shaft.

I will have to open it up and take a look. Thanks!

 

[mcarlo86]

The little motor that drives the numbers was burned out, so $20 used EBay replacement is on the way.