rearend gears
Fleet Owner
Joined: Aug 2005
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From: Easton,Ks
Originally Posted by emiltech
Im changen the rear gearing from 3:73 to 3:08 with a new posi....has anyone done something similar.....any surprises?
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From: BC, Canada
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Joined: Jun 2006
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From: Ottawa, Ontario
Is this a 4x4? If so you have to change the front diff gearing as well. I'm guessing you have a 3spd auto or 4sp manual, because people usually move the opposite direction with gearing.
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Freshman User
Joined: Jan 2007
Posts: 45
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From: Kamloops
changed gearing from 3:73 to 3:08 with posi....what a difference!!! the 351 has gobbs of power and the mileage has jumped up. the speedo is out, so I WILL have to change the speedo calibration.....any helpful hints would be appreciated....
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Joined: Dec 2003
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From: Missouri - Lake of the Oz
speedometer operation & calibration
Originally Posted by emiltech
changed gearing from 3:73 to 3:08 with posi....what a difference!!! the 351 has gobbs of power and the mileage has jumped up. the speedo is out, so I WILL have to change the speedo calibration.....any helpful hints would be appreciated....
Be careful about reprogramming your speedo unit: There are a limited number of changes that it will accept before you have to discard it & start with a new one.
dn.
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Joined: Jan 2007
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From: Kamloops
i havent put many miles on yet....\\\i usually use just over 1/4 tank to go approx 100kms and now the fuel gauge just started to move and im already at 110 kms...the huge drop in rpms to go highway speed makes the big difference..