Axle Ratio Dilemma

#1
Hi,
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.
Thanks,
johnnyP
 
#2
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
 

DL Rupper

Senior Member
#3
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
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
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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