RPMs at Speed

[Nanaeve]

Our 2009 Endura on the International chassis turns 2200 rpm at 60 mph. I feel thats a little fast and have done some research. Seems the transmission, Allison 2500 MH is used on other MH and is a 6 speed not a 5. Checked with the local shop and they stated that its just a matter of programing. If International sayes make it a 6 speed and Allison OK's it too, they program it to be such. Sixth, a second O.D. is .64 while 5th is .74. Thats 1900 rpm at 60 not 2200. I've E-Mailed Navistar to get their take on it, anyone had any experience with it. Seems lots of transmissions out there are 6 speeds . Could be interesting!

[Texas TC]

You should have owned one of the original SuperNova's like mine. They came with 619 gears and at 70 mph, you were winding 3000 rpm's. Luckily, GS and International changed them to the current standard of 529 and the engine speed dropped to 2500 at 70.

I talked to International over a year and a half ago about changing to a six speed and then dropped it after driving the coach more miles. I feel that I would loose power for hills and continuously be downshifting with the six speed. I do tend to drive faster than most and really do not mind the 2500+ rpm's at highway speed limits. I also talked to an engineer at International and he said not to worry about the rev's on this motor. In fact, I got it in writing from him via email.

I have 27000 miles on our Nova and am still learning about these things with each trip. If you pursue the change, let us know the results.