1986 4x4 rear diff

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Nov 11, 2004 | 08:12 PM

civilpe

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1986 4x4 rear diff

I need to replace my 1986 2.9L manual 4x4 rear end with a used one. Mine is a 3.73 gear ratio. The parts house said he has a 3.73 ratio off of a 1987 ranger 4x4 that has a 8.8 ring gear. Does it make a difference if my old one was a 7.7, as long as the 3.73. is the same?

Thanks in advance if anyone can help.

Nov 12, 2004 | 03:32 PM

Ken00

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From: South Jersey

Welcome to FTE!!

I think it will work, anyone??

Nov 13, 2004 | 02:30 PM

backkmann

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replaced differential in '94 Mazda 4x4 with Ford Ranger

you might end up with my problem ??...read on at
https://www.ford-trucks.com/forums/s...d.php?t=305033

do you think I'm having problems because the ring gears are different ? The mechanic says the gear ratio is the same .

Nov 13, 2004 | 05:01 PM

BOJOFASO

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From: NJ

are the tires the exact same size? if the rears are sdifferent from the fronts it will cause the problem you desrcibe.
was the problem there before you changed rears?

Nov 13, 2004 | 05:18 PM

backkmann

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tires changed

I recently changed tires , went from 265 to 235. Do you think it could be the slightly smaller tire...I asked around and the word was it should make no difference. Altho the side sticker in the door frame says use 265 .

Nov 14, 2004 | 10:23 AM

BOJOFASO

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From: NJ

the 235 and the 265 is the width of the tire in millimeters. the 70 or 75 is the percentage of the tread width to the tire hieght. if you have say 265 70 15 tires they are not the same hieght as 235 70 15 tires. the width of the tire will have no effect but if the fronts or rear tires are taller than each other this will give you the vibration.
a small difference is accetable but more than a half inch will put strain on the drive train and will cause the problem.