so i bought my truck about a year ago and still cant figure out what gears it has. my boss thinks there 4.10. i looked at the chart that is posted. but that just confused me. im runnin 33's. when i go 65 (at least i think its 65, over sized tires messed with speedometer) do i turn o/d on or off? with it on my rpm is right around 2100 or 2200. with it off its well over the 3 thousand. i look up the code and it says from the factory it had 3.73. but like i said earlier my boss swears that is has 4.10. the reason i want to know so bad is im thinking about putting 35's on and i wanna make sure i have the right rears for it. another reason to lead me to believe there not stock is the guy before me put a ected locker in it. why would some one put a thousand dollar locker in and not do gears to? so if anybody could help me figure this out it would be awesome.

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2007 xlt ranger reg cab, fll width Ford 8.8 rear, Dana 44 front, 5.13 gears, 37" toyos, pioneer double din deck, rockford fosgate speakers all the way around, custom mossy oak interior, cobra cb, custom stero in tool box(has its own power supply), Diablo intune programmed....Bunch of other stuff.

One way is to pull the diff cover off and count the Count the number of teeth on each gear

Divide the number of teeth on the ring gear by the number of teeth on the pinion gear

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well if i take the diff cover off aren't i gonna have to re fill it and re seal it?

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2007 xlt ranger reg cab, fll width Ford 8.8 rear, Dana 44 front, 5.13 gears, 37" toyos, pioneer double din deck, rockford fosgate speakers all the way around, custom mossy oak interior, cobra cb, custom stero in tool box(has its own power supply), Diablo intune programmed....Bunch of other stuff.

Ya you will only easy way of knowing for sure.

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your axle should have a metal tag bolted on to it on the diff cover, should be on the top part of the cover.

He thinks the previous owner switched gears

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yes you would. one other easier yet less accurate way to check it is to mark a spot on your pinion and a mark on your wheel and count how many times you have to turn your pinion to make one revolution with your wheel. if its over 4 revs of the pinion than it would be a good indication that you have 4:10 gears.

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