towing rpm

john&bet wrote:
I tried it yesterday afternoon and it does not shift into 4th. The torque convertor locks up and it stays in 3erd. If I hit the button at speed it shift down to 3erd and torque convertor unlocks, then a few seconds later the torque convertor locks up again. Just how mine works. Others may be different. I have a Jan.'04 build date, with 325hp,600tq.

45Ricochet wrote:

2500 Grunt wrote:
The 2005 year Cummins is the only year where the tow/haul button once pressed only alters the shift points in gears 1 thru 4 or raises the rpm shift points. It will not lock out 4th gear (overdrive) unless you purchase an aftermarket OD lock out switch/box. Don't know why Dodge engineers did this but they switched back to the other way in 06? To the OP, sounds like you are running in 3rd gear at 2500 rpm's unless you are running 4.56 gearing in 4th? With stock tires with 4.56 gearing in 4th gear you should be around 2300 rpm's at 65mph +/_ (can't find the gearing chart).

Just to clarify, 06 here and the button is a three way switch. Yes push it once for tow/haul which changes shift points, twice it will lock out over drive, third push will be normal operating condition. I believe 2004.5 back they were only a two way switch which would lock out over drive.

Got it! I knew the '03-04 was an OD lockout. I thought the '04.5+ was the same as the '05 but it is not; The '04.5 325 still locks out OD. Strictly '05 models get T/H and get to use OD but do NOT have the ability to lock out OD. '06-07 get T/H AND OD lockout as separate selections.

Thanks for the clarification!!!