Bigger gears for a Jeep

Discussion in '4X4 Truck Talk and Repairs' started by NCCatter, Apr 5, 2007.

  1. NCCatter

    NCCatter Member

    North Carolina
    I am trying to find a 6 cylinder Jeep Wrangler (either a YJ or a TJ) and I want to be able to put a 3" suspension on it to accomodate 33X12.50R15 with 15X10MT Classic II wheels. In order to be able to turn these tires, plus pull my 18' jon boat, I've been told I will need bigger gears. The question is, will 4:10 gears be enough to do what I'm asking, or will I need to go one size up from that? I don't think 3:73 will cut it in the foothills of NC. I don't have alot of knowledge when it comes to mechanical things like this, so any input would be appreciated.
  2. jason454ci

    jason454ci Active Member

    Zanesville, Ohi
    I would think that 4:10 would be plenty of gear. Anything more than that you won't be able to afford to drive it. Also be aware that you will have to change the front gear accordingly. You will also have to get new carriers that will accommodate a 4 series gear.

  3. Mark J

    Mark J New Member

    Four Oaks, NC
    Sounds like you are requesting alot from a 6 cylinder.

    I had the big tire lift kit fascination once. Where does that come from?:lol:
  4. badkarma

    badkarma New Member

    Daniel I had a 1974 cj5 with a 235 6 cylender and a 3 speed trans and I run very large gumbo mudders on it with no problems and one time I pulled a trailer load of pine logs to the saw mill for a friend.That load of logs weighted close to 5 tons(9 16 foot long cuts from 3 2 foot dia. trees) and the jeep pulled it ok once I got it rolling but I had to ride the brakes a long ways to get it stopped.
  5. uapipefitter

    uapipefitter New Member

    Daniel, I have 68' bronco that for years I ran 33's and 4.11's in it. Seemed like the perfect gear for power and mpg. At 55 mph , I would be at 2500 rpm with three speed manual. For years people thought ford's straight 6 was the torquest motor out there for a 6 cylinder. But what they didn't realize is that ford would put a 4.11 or 4.56 gear in to make up for the lack of power the 6 had. I know guys who have pulled the world with their 6 cylinder trucks for years but you'll diffently want to look at something for braking if your boat weighs alot.It's one thing to get it moving,its another to stopping.A 4 wheel drive pick-up will probly be a better set up for you with such a long boat.They have large brakes,V8 motors and a lot of them already have the gears to run those 33's and the lift kits for them are cheap. Good luck Daniel in what ever you go with.
  6. Okie Jim

    Okie Jim New Member

    The 4:10 's will work some what, but if you like using overdrive I would go with 4:56. This will get you back to your original power range. I have a 95' YJ I put 456's in with the 33x12.50 tires and can still take off in 2nd gear.
  7. Brian Wheeler

    Brian Wheeler New Member

    Hey Daniel have you thought about an XJ cherroke with a 4.0.thats what i have and i pull a 19' alum "v" hull i/o. It has 3.55 gears 4" BDS lift and 31-10.5 bfg's
    If you do look for one from 1998-2001 better motor.
  8. Jerry60k

    Jerry60k Member

    Chelyan, West V
    My Blazer has 3.80 gears and positrac and I have no problems at all.

    Anyhow my advice is when you have that rearend built make sure the person doing it uses a metal crush sleeve or else your throwing away money.Jeep used plastic on most of theirs factory and I have helped and overhauled many of them under warranty.
  9. stinky fingers

    stinky fingers New Member

    31'' tires = 3.73 gears
    33'' tires = 4.10 gears
    35''-37'' tires = 4.56 gears
    Throw a locker in it while your at it.