Axle Ratio Dilemma

Discussion in 'General RVing' started by johnnyP, Sep 14, 2006.

  1. johnnyP

    johnnyP New Member

    I have a Dodge Dakota truck (1996, 2 wheel drive, ext. cab, 5.2 l, auto with o/d off-switch) that has an axle ratio of 3.21.
    I have been towing a 3,000 lb trailer for some time (5 years & 10,000 mile cummulative total) and all is well with the truck.
    However, all the info I can find about the towing capability says that a 3.21 axle ratio is not recommended for towing.
    Does anyone understand why this axle ratio is not recommended? (I am thinking of getting a larger trailer; another 500lb). The Dodge people have not been very helpful.
  2. seniorEM

    seniorEM New Member

    Re: Axle Ratio Dilemma

    johnnyP the axle ratio is the torque applied to the rear wheels the higher the ratio the more torque applied, for instance my truck has a 4:10 rear gear which means that in high gear my rear turns 4:1 times for every 1 turn of the drive shaft in your case it is only 3:21 so the heavier the load the easier to get moving with a higher ratio rear gear
  3. DL Rupper

    DL Rupper Senior Member

    RE: Axle Ratio Dilemma

    Will the 500lb heavier trailer also hold more cargo weight? If so you might have a problem. Also are you 100% sure the new trailer is actually 500lbs heavier. Sometimes manufacturers fudge their weight data.

    The good news is your 3.21 axel ratio will give you better milage when not towing.
  4. s.harrington

    s.harrington Senior Member

    Re: Axle Ratio Dilemma

    I had a Dakota 4 cyl. with a 5 speed. towed a trailer full of quads over the mountains with it on a regular basis and never hurt the truck. @180,000 miles the engine developed a noise when started cold so I sold it to a guy who drove it 90 miles round trip to work for a year. He sold it to a kid who wrecked it unfortunately but it had over 250,000 miles when it was totalled. I sure miss that truck.
  5. OldSoldiers

    OldSoldiers Junior Member

    Re: Axle Ratio Dilemma

    The 3.21 is an effeciency ratio. The 4.10 is a power (torque) ratio. 3.21 is really marginal for a TT but might be adequate for a small TT or a trailer with toys on it. Increasing the load is gonna be tough on the little bugger. Good luck.

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