I have a staggered setup on my 94. Bigger-wider on rear. So to determine how far off my speedo was off, i need to find out if the speedo reads off the front or rear tires. thanks

 

I believe its the driver front.

 

Rear tires. Speedo connects to the trans at the tailshaft.

 

wow, 2 TOTALLY DIFFERENT ANSWERS.
Can we get the best 3 out of 5? jk.
burnzya- you 100% POSITIVE?

 

Yes... lol

 

ya speedo goes off the tailshaft of the transmission...so rear tires,

 

wait i thought it was off the fan....jkjk

 

I was told the alternator's signals!!











Yeah, it's the rear tires.

for some reason, when i do 40mph, the GPS reads 38, and when i do 60mph, GPS reads 56mph. FML

 

I'll vouch for the tranny too!

 

Ditto.

My new tires are wider and taller also.. GPS shows I am 5MPH off on Adv.
I loose 1.1 Miles every 10, I have checked it with mile makers and GPS several times..
SO I have remember to add 10% to my miles for gas mileage checks and oil changes.

 

You can always just have it recalibrated.

 

I had thought about checking on it... but now that I know the constant, it is not that bad to deal with. I know on some of my chev hotrod builds over the years that changing it via the small gear that runs off the tail shaft can be a PITB finding the right one you needed to change out.