Mechanics

REPLACING REAR END - MATCHING GEAR RATIO

2005 Ford F-150 • 4.6L V8 4WD Automatic • 110,000 miles

Need to replace the rear end in my F150. I nned to know info on matching up the gear ratio with the front transfer case so all wheels will turn equally in 4WD. Info I have - Axle ratio, 3.55. Axle code, 19. Does this mean that I have to find a rear end with 3.55 gear ratio? I am not a mechanic, but would like to find a used rear end to go in.
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Don F
July 16, 2014.




Yes you need the same gear ratio otherwise you'll need the pcm reprogrammed.

Hmac300
Jul 16, 2014.
Ok, I talked to my guy, he says those numbers are correct for the rear end gear ratio. As long as what he has matches, I'm good. If not I will not take it. Thank you!

Tiny
Don F
Jul 16, 2014.
A lot of the gears are marked like 35-10 on the ring gear which would be a 3: 50 ratio so if you pull the cover off you could see it but the guy probably know what he is talking about.
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Hmac300
Jul 16, 2014.

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