A833 Speedo Gear Drive Question

it might be an issue with your speedometer....go on a nice freeway cruise and check your odometer compared to mile markers over say 20-30 miles to make sure the discrepancy between the speedometer and odometer match. I have slightly taller than stock tires on back (225/70R14). my speedometer bounces some at lower speed, and is consistently 10% high (70MPH indicated is 63 via GPS), while my odometer reads 3% low (33 miles indicated was 34 miles actual), which is what I would expect with the tires I have vs. the original D78/14 height....