I have a 2wd 94 4.0 with an a4ld and 3.08s. i recently got 255/70/15 tires in the rear, and it came with 14" rims stock. my speedometer is about 5-6 mph off and i was wondering if there was any major difference between the gears, and if i could get like a (for example) 19 tooth gear that would true up my speedometer. i plan on a 3.55 lsd regear eventually, but wondered if id be able to do anything. i think f150s had 3.08s with 15" tires, so maybe that would work, but i need some advice
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A4LD has the speedometer DRIVE gear machined onto the output shaft, image here: https://www.ebay.com/itm/312723095475

Looks like 7 tooth to me, this matters

Then go here: https://www.tciauto.com/speedometer-gear-calculator

7 tooth
3.08 ratio
29.1 tire diameter
Calculate

= 14.9, so a 15 tooth DRIVEN gear, not sure Ford ever made 15 tooth driven gear so may be stuck with 16 tooth until change to 3.55, which would use 17 tooth

If this is way off then you "may" have an 8 tooth DRIVE gear in YOUR A4LD if 3.08 was factory ratio, can have either, recalculate using 8 instead of 7

Ranger manual trans and transfer case all used 7 tooth DRIVE gears