bsummit
Arkansas Chapter Leader-Retired
I towed my big horn with mine for the first time this week on a trip south and I run in 5th gear with tow/haul at 2200 rpm and it did great. I will be pulling in the hills of north Arkansas next week and with past experience with my other dodge, what ever gear you want to run in as long as it's not in the red.
beardedone
Beardedone
I never went past 2200 in the mountains of BC and I prefer to leave the motor running around 1700-2000 and then shift down as required. These new transmissions are so nice with the paddle shift are really handy.
Ray LeTourneau
Senior Member - Past Moderator
GORDINEER, I think the question wasn't who could get there first. The majority of us aren't interested in getting there first, just getting there in one piece.
Ralphpam, your rpm will go up if your trans downshifts going up a 6% grade. I know out Dmax would. The main thing is to try to keep the temps down and the RPMs below red line.
Nabo
Southeast Region Director-Retired
It all depends on how fast you want to get up the grade!!! and strain the motor. We have a 09 srw 6.7 dodge and running the mountains around east TN in tow haul, big red usually stays around 2100 to 2200 rmps at a speed of approx 60ish up a 5-6% grade. At that speed it usually doesn't down shift but when it does, it will run around 2800-3000 rpms.
OK me wrong- just took the BC up to Bristol to set up for next week Nascar races and the 09 dodge runs at 1600-1700 at around 70ish. When it downshifted to pull a hill it ran up to around 2300 and then settled back to 2100. The other dodge 2500 (2005) was the one that ran the above numbers. Sorry about that.
OK me wrong
- just took the BC up to Bristol to set up for next week Nascar races and the 09 dodge runs at 1600-1700 at around 70ish. When it downshifted to pull a hill it ran up to around 2300 and then settled back to 2100. The other dodge 2500 (2005) was the one that ran the above numbers. Sorry about that.
Last edited:
TXBobcat
Fulltime
Regardless of what your truck is the main thing you have to do is keep the rpm's up for two reasons.
First, you need the rpm's high so your truck will not lug down. This is hard on the truck to lug it down and you will loose speed. Go to a lower gear. My truck runs 70mph at 2000 rpm. If I am going up a grade and the rpm's drop down and it is loosing speed and has not shifted, I press the gas peddle and make it down shift to keep the rpm's up.
Second, If your rpm's are low you are not circulating water through the engine and the oil in the transmission is not moving fast enough to keep it cool.
I asked the diesel mech at my dealership and he said 2000 is a good normal rpm. It can go up to 3000 with no problem but if it gets over 3500 more than 20 minutes or so drop the rpm's back down to around or below the 3000 range but try to keep it below 4000 rpms unless absolutely necessary.
Contact your mechanic and see what he has to say.
FWIW
BC
First, you need the rpm's high so your truck will not lug down. This is hard on the truck to lug it down and you will loose speed. Go to a lower gear. My truck runs 70mph at 2000 rpm. If I am going up a grade and the rpm's drop down and it is loosing speed and has not shifted, I press the gas peddle and make it down shift to keep the rpm's up.
Second, If your rpm's are low you are not circulating water through the engine and the oil in the transmission is not moving fast enough to keep it cool.
I asked the diesel mech at my dealership and he said 2000 is a good normal rpm. It can go up to 3000 with no problem but if it gets over 3500 more than 20 minutes or so drop the rpm's back down to around or below the 3000 range but try to keep it below 4000 rpms unless absolutely necessary.
Contact your mechanic and see what he has to say.
FWIW
BC
cdbMidland
Past Michigan Chapter Leader
What does Dodge CTD stand for?? Circling The Drain?? Bwaaahaaahaaa
I believe it stands for Cummins Turbo Diesel.
dieselengineer
Charter Member
To pull a grade, it takes torque from the prime mover. So the best rpm for pulling is at the engines maximum torque point on the torque curve. For the CTD, this point is 2100 to 2200 rpm depending on the fueling curve. This also normally the best point for maximum fuel mileage, if high output is being demanded. Therefore, I normally tow at this rpm or just a little above so I am at maximum torque after the turbo lag clears. With this setup, the only reason I need to down shift is for slow traffic.
rick_debbie_gallant
Well-known member
so it sounds like perhaps towing in 5th speed (gear) in the tow haul mode?
Ray LeTourneau
Senior Member - Past Moderator
I'm not too familiar with Mopar trannies. Is there actually an overdrive in the 6 speed (which would then make it a 7 speed) or is it really a torque converter lock-up in 6th gear?
On edit, I did my own homework. here's a link to the dodge tranny page. http://www.dodge.com/en/2009/chassis_cab/capability/transmissions/
Sounds like a pretty good trans!
Last edited:
beardedone
Beardedone
Hi Ray that transmission you mentioned is actually the Asin transmission which is only available in the 4500 / 5500 series. For most of us with the 3500 or 2500 it is a different transmission. I can't remember the name of ours but it is different.
HarleyRyder
Retired Gunslinger
The 6-spd automatic transmission in Dodge 4500/5500 with Cummins diesel is an Aisin AS68RC "Commercial Grade".
The 6-spd automatic transmission in Dodge 2500/3500 with the Cummins diesel is a 68RFE (Orion).
The 5-spd automatic transmission is available behind the 5.7 Hemi in the 2500.
In comparing the 2008 and 2009 sales brochures, the Hemi was available in the 3500 in 2008 but not in 2009. The 6.7 diesel is the only engine offered in the 3500 for 2009.
The 6-spd automatic transmission in Dodge 2500/3500 with the Cummins diesel is a 68RFE (Orion).
The 5-spd automatic transmission is available behind the 5.7 Hemi in the 2500.
In comparing the 2008 and 2009 sales brochures, the Hemi was available in the 3500 in 2008 but not in 2009. The 6.7 diesel is the only engine offered in the 3500 for 2009.
Ray LeTourneau
Senior Member - Past Moderator
This is a clip from the link. My original comment/question was regarding the overdrive. Weather or not it's a true overdrive or just a torque converter lock up. It was more out of curiosity than anything. It does appear though, that the Aisin is available in the 3500 series trucks.
