I recently swapped a '92 ABS rear with my failed 91 (no ABS) rear axle. The wagon runs great although I appear to be travelling everywhere at 120 MPH.
It seems that the '92 with ABS sends abs signal in addition to speed. It also appears that swapping the switch will not work as the internal reader is not the same mechanism.

Any ideas for work arounds? Do I need a new cluster or can I manage this in some other way?

WAGON 1991 245 no abs.
Axle 92 with ABS.

 

IIRC< the ABS and non-ABS have different 'tone wheels' with a different number of pulse counts per turn. short of swapping speedos, yeah, nothing you can do. you'd have to disassemble the whole differential to swap the tone wheel inside.

 

Either that or get a speedo cluster from a '92. You might want to check out this link:

Electronic Speedometer Notes

I vaguely recall reading somewhere about modifying the cluster to work with a different tone ring. You may also want to read up on Dave Barton's page (DaveBarton.com). I believe he had articles relating to the different tone rings as well.

 

I'm not in any way interested in disassembling a differential. Looks like an instrument cluster is the way to go.

 

I'll look around for that modification. I'm more of a nuts and bolts guy then an electronics guy. I'm certainly not about to bench test a speedometer...I'll hit up the WWW for an instrument cluster.

 

the mod is basically a phase lock loop pulse divider unless the ratio is integer, then its a simple digital divider. they sell these as a module for the custom vehicle world to deal with different tire sizes that you can setup for any percentage correction you need.