I've been working on a diesel transplant in my 1992 80 series truck, where an old 1HD-T replaced an 1FZ-FE with broken head gasket. The diesel transplant called out a different wire harness which required a different instrument cluster, which has a cable directly from the transfer case into the back of the cluster (not electric signal). During the first test run with the cluster installed, the speedometer showed something like 4x to 5x the actual speed of the truck. Does anyone have an idea about what could be happening?
The truck is on 39x14.5R15 IROK tires and the old speedometer was very accurate on those tires. I was quite surprised seeing this behavior.
A pic of my truck...
The truck is on 39x14.5R15 IROK tires and the old speedometer was very accurate on those tires. I was quite surprised seeing this behavior.
A pic of my truck...