Why 4.1 axle?

valhalla360 wrote:

JRscooby wrote:

Are we discussing why somebody would pick a given rear ratio, in this case 4.1 to 1, right? I don't have much experience with light duty stuff like what RVs use. What I have done is decide how much weight I need to move to make it pay, then try put the gears and axles under the frame to get the job done. If you got 50,000 lbs on your back, and the customer says "Take it across that bean field, dump at the tree line" You are going to grab a double handful of seat with both hands on the wheel. If you thought the 4.1s could save you fuel over the 4.44s you start counting how many gallons you could buy for the cost of the power divider. That old Pete with the 1693 Cat, 2 stick 5X4, and 5.56 was the best I ever had for that kind of work, but hard to feed on a lot of other jobs...

Again, if you need a higher tow rating yes a higher numerical rear end can help...I said that in my first post.

No matter how the weight compares to the rating, for a given weight, all other things equal, a higher numerical rear end ratio will put less strain on the rear end housing, the rest of drive line, and the part of the frame that joins engine to rearend. This is the reason the manufacturers change the ratio when they change the rating.

If you aren't exceeding the weight ratings, a different rear end isn't going to have much of any impact with new trucks with 8/10 speed transmissions.

If you have 40eleven speed transmission, and a lower speed rearend you have more choice of transmission ratios for given road speed than with a higher speed rearend. This improves the chance the engine is running at preferred RPM. The fact that your preferred is for increased power, better mileage, or less noise does not mater.