Anonymous
Anonymous asked in Cars & TransportationCar MakesFord · 1 decade ago

1967 Ford F150, Will I need to swap rear end if I go from straight 6 to V-8 with 4 speed trans?

I want to go from straight 6 to V-8 with a 4 speed trans (Granny), will the current rear end need to be swapped out due to the power difference.

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  • 1 decade ago
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    If memory serves that truck should have a 300 ci thats the big 6. -9 inch rears are bullet proof.do it

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  • 1 decade ago

    That's a 9" rear gear in there and they are one strong unit.

    While the basic design is a bit less efficient than others

    (Hotchkiss vs Salisbury) you won't have any reliabilty

    problems assuming its greased. Also, gear ratio changes

    are fairly cheap and easily accomplished by any shade-

    tree mechanic with common hand tools and there are

    parts galore for that rear. As most all final drive trans

    ratios of that era were 1:1, you shouldn't need to change

    your speedo driven gear but if you do, that's easy and cheap

    as well.

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  • 1 decade ago

    Just change the motor and tranny and go with the rear end that is there. I have done this to a bunch of trucks and have never encountered a problem with too much horse power from switching from a six cylinder to a V-8. With a granny low I don't think you are building a race truck. Let us know how it turns out.

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  • 1 decade ago

    It depends on what number of horsepower you are making and how you intend on driving it. If I am not mistaken that is a ford 9 inch rear end in that vehicle. Dependable up to 500+ horsepower. You may want to rebuild the rear end for reliability purposes because of the horsepower and torque difference between the 6 and 8 cylinder engines.

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  • 1 decade ago

    wouldnt matter...but the 6 cyl. rear end is probally gonna be geared lower than a v-8 would . not gonna hurt it ... cept maybe ya gas mileage..only thing that should be different are the gears on the inside an u can swap those if ya not happy with the 6 cyl rear end.. but ya probally gonna have ta beef up the front end for the engine swap an check ya hood clearance

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  • Anonymous
    1 decade ago

    The old adage is don't fix it till it is broke. If you change the tranny you will need to find out gear ratio in rr end and what the trannys final drive is along with tire size to figure out what speedo gear you need to know how fast you are going so the speed odometer is correct

    Source(s): GM emp 31 yrs and a backyard mech with friends who are the same
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  • 1 decade ago

    yes you will .the gear ratio will be different resulting in less direct drive to rear tires. you would need to change gear ratio .

    in other word's i don't know.

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