looking to change my axle ratio

Loaded for some is 80k lbs or under. Loaded for others is 100k lbs and over. Rather large difference there...
On a lighter note...

 

BUT, not everything else is equal. You would spec a taller gear in the trans to make up for the shorter gear in the final.
Running in direct is not just saving parasitic loss, its creating more output torqe then a trans in overdrive. This seems to be the part your not getting. You would never run a 3.55 in direct for crusing since it would be to slow. You would never run a 2.64 in od because it would have no power. When you run a 2.64 with a direct, or a 3.55 in Od you get approx the same torque and speed. You would never spec a 2.64 with "everything else being equal."

Your eating up torque by running the 3.55 in OD. by not running in OD were not loosing the tourqw that you normally would. (take out the fact that dirrect is more efficient) you still wont end up with less torqe at the wheels.

 

Last one for a while.....
Even good old Scotty knows the difference!


Martin

 

Hey kids!

Take the sillinesss here:

http://www.thetruckersreport.com/tr...teen-wheelers/251928-direct-vs-od-setups.html

 

So if that were true, then why would every truck not switch to that setup?

If I pull my 4.10's out, throw away my 18B, and put in a 10 direct with 2.64's then by your methodology as long as I stay on highway (which I do) I will notice no difference? My truck will pull just as good as it does now? Only I will get better fuel mileage? Cause the torque that I would inevitably put to the ground would be the same, right?

And I cannot believe with all of the bright engineers that there are, that it has taken this many years for this revelation to come to light.

 

why spread around like a virus. one thing I will say is direct drive running cooler. doesnt work with what I do. explain to me why all my trans I have owned would heat up in direct and cool down in overdrive.

 

Same thing on my last truck, Trans temp higher in direct vs overdrive.

 

I guess I have been doing it wrong all these years. haven't learned a dang thing!