Pros and cons on dropping to 3.42 gears

[KevinD]

What are the pros and cons for dropping to 3.42 gear? Wanting better mpg on interstate.

 

[zf>allison]

http://www.duramaxdiesels.com/forum/showthread.php?t=35241

Little info there. Not sure about mileage gains. Your looking at a grand probably to change gears front and rear that's a long time for fuel savings to pay them off

 

[prostreeter600]

I have heard of people doing it more for racing purposes to gain MPH coupled with the fact that with our diesels producing so much torque it would propel the vehicle better without zipping thru our usable rpms . But I was also told it was not the best thing for the street and that the allison would tend to hunt more for the right gear versus the 3.73 gear . Keep in mind the bigger the tire you run it will worsen that situation . I hope this helps answer some of your questions .