Haven't gotten mine running good enough to try it yet.
But to all of the ones posting on here with lifts and bigger tires...have you allowed for the fact that your speedo is not accurate so your miles are not?
On my 85 F150 when I went from stock tires to 33's my speedo was off by right at 5mph.

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1994 Ranger XL extended cab. 3.0 auto. all stock for now. Just bought for my 16 year old son.