Whats The Best Gear Ratio For A V6

Discussion in 'SN95 V6 Mustang Tech' started by Alex96stang, Sep 21, 2006.


  1. Alex96stang

    Alex96stang New Member

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    HI guys and gals

    I am about to change the gears on my car ang i was wondering what is the best gear ratio for a auto transmision and do you know where do i can get the speedo gear that matches the gears on my rear end
  2. Give Me TP

    Give Me TP New Member

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    I would go with nothing other than 4.10's for a DD street car, but some people are bound to say you should not go higher than 3.73's.
  3. Skymarshal

    Skymarshal Member

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    AFAIK, to correct the speedo you need an electronic converter. Since the tranny is computerized, I don't think you can just put a different tooth pinion on your speedo cable.

    And I'm going to put 3.73s on my 5-speed. I think that will wake the car up without killing your mileage. IMHO, you don't need 4.10s unless you go to the track regularly.
  4. Give Me TP

    Give Me TP New Member

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    We have had 4.10's on my wife's 04 V6 automatic for two years now. It's a daily driver and has been on two 2000+ mile road trips, and gas mileage dropped maybe 1-2 mpg. Well worth it for waking up the car in our opinions.

    On a pre-98 model I think Alex is correct in needing a speedo gear for his transmission.
  5. AP1995V6

    AP1995V6 New Member

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  6. Alex96stang

    Alex96stang New Member

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    Hi Guys and Gals

    My car is a 96 V6 convertible with automatic transmision
    i was told that they came with diferent gear ratio from the 5spd

    so the upgrade depends ons the gears that have now on my car

    I have my eye on a set of 3.45's from richmond gear
    cause i think that are much better than the 2.73's that i have
    plus since is my daily driver and i do drive it a lot
    i dont wanna go to wild
  7. Alex96stang

    Alex96stang New Member

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    Does anyone has 3.45’s in there car

    And if so there are much better than the stock 2.73’s

    and another question what other cars have 7.5 rear ends and with what gear ratios splines they come with
    i've heard that the Mustang, Fairmont, Thunderbird, Mercury Capri, Cougar, Zephyr, Ranger Pickup, and Bronco II come with 7.5 but i'm not sure og the gears that they have
    I've also heard that bronco II came with factory t-lock

    cause i have a friend that works in a junk yard and he can give a very cheap price on the center section of the diff
  8. Henceforward

    Henceforward The Avatar Master Founding Member

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    I can't see how getting anything less than 4.10s installed in a slushbox V6 would be worth the money.

    I would even run 4.10s in my car if I had to do it again.
  9. AP1995V6

    AP1995V6 New Member

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    4.10s don't make that big of a difference unless you drive 80 every where you go as far as gas is concerned.
  10. 97sally6

    97sally6 New Member

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    they dont make 3.45's for the 7.5 rear, unless its a recent thing. get either 3.73's or 4.10's. and to correct the speedo you need either a speedo gear or a speedcal from dallas mustang.
  11. Alex96stang

    Alex96stang New Member

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    i was planin to get the center section of a use rear end cause i got a friend that works in a junk yard so pretty much i need to know wich car have the 7.5 rear end and what gear ratio do they have and in the 2006 frpp they have 3.45's

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