cluster woes

[DerekTheGreat]

I did the swap on our truck a while back. Lucked out at a junkyard. Thing to keep in mind is that they also have an internal DRAC module that handles the speedo. What that means is that if the rear gear ratio that cluster was set up with is different from your truck you will need to modify it to work correctly, otherwise the speedometer will be off. I believe someone posted the link to that information. OP, do you remember what ratio that cluster was for? I want it if it's set up for 4.10's.

 

[un4givn85]

The only thing I know about the truck it came from is that it is a 91 K2500 with the 454.
Did not get any further information from it.

 

[someotherguy]

If I was in the market for a 1991 needle cluster, has hard as they are to find, I wouldn't let its original settings stop me from buying it...really not hard to change.

Richard

 

[drewcrew]

If I was in the market for a 1991 needle cluster, has hard as they are to find, I wouldn't let its original settings stop me from buying it...really not hard to change.

Richard

Richard, since I own a 91 I'd like to know what the differences are in a 91 cluster. Thanks

 

[someotherguy]

Richard, since I own a 91 I'd like to know what the differences are in a 91 cluster. Thanks

The 1988-1991 clusters are significantly different from 1992-1994 in several ways. Most are aware of the 1988-1991 "moonie" gauges so that's the obvious difference. However electrically they are different too, as was mentioned earlier the DRAC (speed sensor buffer essentially, this is where you would make changes to calibrate the speedo based on your tire height and gear ratio) is built into it rather than as an external module on 1992-1994 (and 1995 too although it's the newer interior with a totally different cluster.) 1988-1991 has a pin style socket for the harness vs. the "fingers" style from 1992-up.

1991 brings about 2 changes compared to 1988-1990; they moved a few things around on the pinout (see previous replies in this post about that) - and also for the first time, needle style gauges including tach were available for these trucks. Some 1991's got moonies, some got needles, depending on how the truck was optioned. So in a nutshell a 1991 cluster of any type is a "1 year cluster" although it can pretty easily be used in a 1988-1990 with minor changing of some pins in the dash harness connector. It's the easiest path for a 1988-1990 owner to get needle gauges, providing they can actually source a 1991 needle cluster.

Richard

 

[un4givn85]

Thanks for that info Richard

 

[drewcrew]

The 1988-1991 clusters are significantly different from 1992-1994 in several ways. Most are aware of the 1988-1991 "moonie" gauges so that's the obvious difference. However electrically they are different too, as was mentioned earlier the DRAC (speed sensor buffer essentially, this is where you would make changes to calibrate the speedo based on your tire height and gear ratio) is built into it rather than as an external module on 1992-1994 (and 1995 too although it's the newer interior with a totally different cluster.) 1988-1991 has a pin style socket for the harness vs. the "fingers" style from 1992-up.

1991 brings about 2 changes compared to 1988-1990; they moved a few things around on the pinout (see previous replies in this post about that) - and also for the first time, needle style gauges including tach were available for these trucks. Some 1991's got moonies, some got needles, depending on how the truck was optioned. So in a nutshell a 1991 cluster of any type is a "1 year cluster" although it can pretty easily be used in a 1988-1990 with minor changing of some pins in the dash harness connector. It's the easiest path for a 1988-1990 owner to get needle gauges, providing they can actually source a 1991 needle cluster.

Richard

Thanks for your time and all the info. Mine has the tach and needles and that's the one I want. Thanks again.