Quote
I'm running a 4.88 with 33's and I checked what the speedometer says compared to the GPS. Here is what I got(5th gear 22re w56):
RPM...Speedo...GPS
3000..68..........60
3200..73..........66
3400..78..........70
3600..84..........76


Looks to me like a perfect match, just like the math predicts.
Any gear ratio offset would cause the error to grow with speed (constant % error).
Looks to me like somebody has done a "poor-man's correction" on this truck, lol. I did this by moving the needle.

FWIW, I'm using 4.88s and 32s on an A/T. Find it's a good match. Math works out to stock ratio, although Toyota put 31s on this combo making that OE setup a little overgeared.

With 200+ Billion electrical parts, the world most complicated machine is inside your own skull.

Question Reality.
-----------------------------
'89 Rnr DLX "SR4.5", 32s w/ 5.29 locked f/r blah blah