rear gears

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Apr 30, 2002 | 01:46 PM

79crazee

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rear gears

Oct 17, 2002 | 04:40 PM

oft

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From: Burke VA

rear gears

Hello all,

I have a 2 wheel drive 78 that originally had the I-6 with a 3 on the tree standard trans. Anyone know what gears would be in the rear? I have since changed the 6 out for a 351W and I am wondering if I should do anything to the rear.

Jayson
78 F100
93 5.0 GT
96 Taurus Wagon

Die Hard Ford Fan.

Oct 17, 2002 | 04:43 PM

mudder trucker

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From: british columbia

rear gears

if you leave the vin# some one will have an answer. mudder trucker.

Oct 17, 2002 | 04:46 PM

oft

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From: Burke VA

rear gears

OK,

Here it is,

F10BCAG9391

Any other info from the vin would be great as well.

Jayson

Oct 17, 2002 | 07:30 PM

73Highboy

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From: Clarkdale USA

rear gears

Usually those trucks come with low 3.xx gears. pull off your rear cover, and there should be three sets of #s under were the pan bolts on. first two are two digit #s, those are how many gears are on the pinion and ring. the pinion is your smaller #, ring is bigger. divide your ring # by pinion at that will give you your ratio. I'm sure you shouldnt have to change it, but if you want more go off the line, go a little lower, but dont go too low, so you have some top end.

Oct 17, 2002 | 08:27 PM

oft

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From: Burke VA

rear gears

Well, thanks 4 the advice but I was hoping I wouldn't have to open up the rear diff. Don't need 2 know that bad!

Jayson

Oct 17, 2002 | 09:34 PM

tetraruby

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rear gears

79F100 that had a six behind it...you most likely have a nine in the rear. Good luck trying to get the "cover" off. Check for a metal tag that usually is on one of the third member bolts. I'm sure it'll be grimey...post the numbers exactly how they appear the tag. You could also try raising the rear end and counting the number of driveshaft rotations for each tire rotation...beats tearing into the rearend.

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Oct 17, 2002 | 10:30 PM

Torque1st

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Joined: Sep 2001

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rear gears

Jayson, the reason they said good luck with the cover is that a 9" rear axle does not have a cover, the whole diff assy (pig) unbolts from the front of the axle assy. Most of the time the diff ID tag is on the passenger side under one of the bolts at about the 8 o-clock position. If you have a door tag there are numbers on it that will identify the axle assy also.