Would 6 Spd Trans Give Me Better Od W 3.73

Discussion in '1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-' started by 90lxwhite, Dec 22, 2013.


  1. 90lxwhite

    90lxwhite Well-Known Member

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  2. Grabbin' Asphalt

    Grabbin' Asphalt Advanced Member

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    5spd DD needs a 3.55, so you trying to make it up with a 6th gear tranny for a 3.73??
  3. A5literMan

    A5literMan Advanced Member

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    Umm... Lot cheaper to change the gears. Just saying
  4. 90lxwhite

    90lxwhite Well-Known Member

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    Ah I know.. But I'm only making 233 n 281 tq and I think the 3.73 gear is the only thing keeping me in the game. I'm afraid the 3.55 wouldn't be enough of an rpm drop to justify switch and 3.31 would lose too much low end. It'd not a dd but driving any kind of distance gets old(30-50 mi)
  5. 02 281 GT

    02 281 GT Active Member

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    I would say that it depends on the ratio of the overdrive gear.
  6. 90lxwhite

    90lxwhite Well-Known Member

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  7. 02 281 GT

    02 281 GT Active Member

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    Well, according to this chart, pretty much all factory Ford 5.0 Mustangs equipped with a T-5 had a .68 5th gear ratio. The Tremec in the link has a 6th gear ratio of .63. That will be a slight improvement over .68 on the highway, however, it seems far too miniscule to make a noticable difference in the revs at those speeds.

    The main advantage of upgrading to a 6-speed is that the extra gear helps spread the ratios around so that it's easier to keep the engine in the neighborhood of revs where it makes the most power.

    Comparing the ratios of the stock 5.0 T-5 and the 6-speed in the link shows that you would have more useful 1st and 2nd gear ratios (2.66 vs 3.35 and 1.78 vs 1.99). The biggest advantage comes in road racing when you get to the .80 fifth gear that helps fill the gap between the 1.00 4th and .63 6th gears.

    In the end, you wouldn't really gain much if your main objective is to have fewer revs on the highway.
  8. stykthyn

    stykthyn Commander of the snuggie cultists

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    you looking for gas mileage? Reducing rotational mass may be your best bet to save gas and make your car quicker.
  9. revhead347

    revhead347 I have face herpes.

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    If you want a 6 speed look for a T56 with a .50 sixth gear. That will help more. It's still going to cost you about 4k to get it in the car. There are cheaper ways to make it better.

    Kurt
  10. 90lxwhite

    90lxwhite Well-Known Member

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    It's not so much the gas mileage but the whaaaa and the constant pulling in 5tb on the hwy that gets old. Y'all know of anyone who ran a 3.31 behind a t5?
  11. A5literMan

    A5literMan Advanced Member

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    I don't understand your dilemma?! You just don't like the rpms you're pulling at highway speeds. So? What's the big deal? It's only turning what 2600rpm at 70 or so? Not trying to be a di ck but that's pretty minor. Through some 3.08-3.27 gears in it. Performance will be hurt but you'll have less highway rpms. I can't see throwing a 4k transmission at the problem. If you want the trans I say go for it! It's badass and will support any further power you may make in the future. But just to do it because of the hwy issue seems extreme
    f8tlfiveo likes this.
  12. mikestang63

    mikestang63 Mustang Master

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    I agree with the others. You want to spend 4k on a 6sp and to go from a 3.55 to 3.73, and you think it will be noticeable? For 2k, throw a Vortech on it and your problems are solved.
  13. 90lxwhite

    90lxwhite Well-Known Member

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  14. Grabbin' Asphalt

    Grabbin' Asphalt Advanced Member

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    For a DD 5spd, highest i would go is a 3.55 regardless of power in my book, it's already boardering on a lot of whaaaaaaa on the hwy :eek:
  15. RangerJoe

    RangerJoe Active Member

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    I thought you hated your 3.73's. Maybe I am confusing another user, but weren't you considering dropping down a gear size anyway? Like other's said, its a lot cheaper to do a gear swap.

    Joe
  16. John Dirks Jr

    John Dirks Jr Active Member

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    I have 3.73's and I don't mind the rpm's at 70mph. For me, the whole package is a bit quieter at 25-2600rpm. When I drop down to 60mph and the engine is in the 20-2200rpm range, the engine makes that low tone droning resonating in the exhaust. Overall, to me that's more irritating than the higher rpm's. Definitely quieter at 2500 than 2000 in my car.

    I agree that for 4k, I'd be looking into forced induction. Then you can drop your rear ratio without loosing acceleration performance.
  17. Audiophile

    Audiophile Active Member

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    I have 3.73s, and I don't really have a problem with turning more RPMs on the highway. If I remember correctly, I'm doing about 400-500 more at 70mph than I was with the stock 3.08s. I just made a drive across the country, and to my surprise, I got about 21 mpg. Seems halfway decent.

    I'm no expert, but I can say I agree with the others. I just can't see spending $4K on a new transmission, that is, for this issue alone. However, to each his own! Good luck with whatever you decide to do!
  18. Mustang5L5

    Mustang5L5 Car used in adult film "Highway Gangbang-InDaButt" SN Certified Technician Founding Member

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    That would be me that's hates me 3.73s



    Not about to swap to a t-56 though. I'd either drop to 3.55s or purchase an aftermarket t-5 5th hear with a taller ratio
  19. RangerJoe

    RangerJoe Active Member

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    I think he posted on here recently stating that he had no first gear with his 3.73's. I could be wrong though, it sure wouldn't be the first time.

    Joe
  20. RangerJoe

    RangerJoe Active Member

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