Pulling grades RPMs

[RVTRKN]

1st concern is EGT, and with stock programing, its hard to go beyond its limit, if truck picks its own gear and RPM.

2nd concern is transmission stress, overdrive should never be used pulling grades loaded, with the G56/NV5600 never use 6th pulling grades and turn off overdrive on the auto's.

Keep your RPM's 23-2500 while climbing to keep EGT's down. Its what I have learned with the two CTD's I have owned/own. But they are/were manuals, and its very critical to keep my RPM's were they should be, seeing how it wont downshift on its own.

 

[NIsaacs]

1st concern is EGT, and with stock programing, its hard to go beyond its limit, if truck picks its own gear and RPM.



2nd concern is transmission stress, overdrive should never be used pulling grades loaded, with the G56/NV5600 never use 6th pulling grades and turn off overdrive on the auto's.



Keep your RPM's 23-2500 while climbing to keep EGT's down. Its what I have learned with the two CTD's I have owned/own. But they are/were manuals, and its very critical to keep my RPM's were they should be, seeing how it wont downshift on its own.

That seems a little harsh, no overdrive on hills? With the 6 spd autos that means towing up hill in 4th??



Nick

 

[RustyJC]

1st concern is EGT, and with stock programing, its hard to go beyond its limit, if truck picks its own gear and RPM..... But they are/were manuals, and its very critical to keep my RPM's were they should be, seeing how it wont downshift on its own.

Yes, it WILL downshift on its own, when the engineers who programmed the computers decide that it needs to. One certainly has the capability to override all the programming with the +/- switch, but why not put it in tow/haul whenever possible and let the big dog hunt just the way the engineers intended? After all, they tested it and they warrant it, so if it were going to spit overdrive all over the road, I'm sure they would have provided for an overdrive lockout function in tow/haul, right?

Rusty

 

[HBarlow]

As usual, RVPoser has no idea what he's posting about. He doesn't own gauges, has never owned a set of gauges, and has no idea what his egt is. He thinks and has argued here for years that a Cummins has to be wound up to 2500 rpm to pull a grade. Clueless.

He has also never owned an automatic so is just posting nonsense about how an automatic will respond.

 

[RVTRKN]

As usual, RVPoser has no idea what he's posting about. He doesn't own gauges, has never owned a set of gauges, and has no idea what his egt is. He thinks and has argued here for years that a Cummins has to be wound up to 2500 rpm to pull a grade. Clueless.



He has also never owned an automatic so is just posting nonsense about how an automatic will respond.

YUP, I don't let a TCM (transmission control module) that you seem to think that doesn't exist, control my transmission. I also don't care what you do with any vehicle you drive. I'm not answering your thread, but this thread is not yours, and have answered the OP's question.



If the 68rfe will not protect itself when you chose your own gear (+ - switch) then treat it as a manual, tow haul mode should be OK. I'm sorry about the overdrive statement, I forgot about the different TCM programming with the Aison and the 68rfe and was referring to the 48re.

 

[RVTRKN]

My truck is stock and will remain that way until all warranties are over. YOU DON'T NEED GAGES IF IN STOCK CONFIGURATION IF WITHIN THE DODGE RECOMMENDED GVWR/GCVWR.

 

[HBarlow]

Clue for RVPoser: The Cummins engine warranty is five years/100k miles. It is now August of 2012.

 

[Jim W]

Harvey,
RVTRKN; is incorrect in his statement of the MY of his truck or else he has a 5. 9L engine in the 07. I believe that the 6. 7L engine first appeared in Jan 07 which would make the truck a 07. 5MY. I also believe the warranty period starts for new trucks from the day of purchase; so he may have bought the truck in August or Sept off of the dealer lot. So he could still have about one or two months of warranty left on the engine maybe?
Jim W.

 

[AH64ID]

An 07. 5 is still an 07. Many people call their 6. 7 MY 07s a 07. 5, but the official MY is 07, 07. 5 is nothing more than slang, like CTD or C&C.

Yes warranty starts at date of delivery. A 6. 7 MY07 could have a date of delivery even into 2008, so it is a distinct possibility that there is motor warranty left. In addition some MY trucks had a 7/100 on the motor, mine being one. I am not sure what the MY07 carried.

EDIT: MY07 was back to the 5/100, but carried a 7/70 on some of the HD emissions equipment.

 

[RVTRKN]

Clue for RVPoser: The Cummins engine warranty is five years/100k miles. It is now August of 2012.

There still is a 7 year 70K extended warranty dumb ash

Harvey,
RVTRKN; is incorrect in his statement of the MY of his truck or else he has a 5. 9L engine in the 07. I believe that the 6. 7L engine first appeared in Jan 07 which would make the truck a 07. 5MY. I also believe the warranty period starts for new trucks from the day of purchase; so he may have bought the truck in August or Sept off of the dealer lot. So he could still have about one or two months of warranty left on the engine maybe?
Jim W.

You could get an MY07 C&C with the 6. 7 in 06 and I ordered mine in Jan 07 and took delivery in March and is not a 07. 5 MY.

An 07. 5 is still an 07. Many people call their 6. 7 MY 07s a 07. 5, but the official MY is 07, 07. 5 is nothing more than slang, like CTD or C&C.

Yes warranty starts at date of delivery. A 6. 7 MY07 could have a date of delivery even into 2008, so it is a distinct possibility that there is motor warranty left. In addition some MY trucks had a 7/100 on the motor, mine being one. I am not sure what the MY07 carried.

EDIT: MY07 was back to the 5/100, but carried a 7/70 on some of the HD emissions equipment.

Hsmartash read this last line.

When climbing a grade in the CTD heavy, bogging is a death sentence for it. Again, the reason for the RPM's is to intake more air for the Air/Fuel mixture allowing to help in cooling the exhaust. When bogging a CTD or any Diesel for that mater, causes the EGT to rise due to more fuel than air to mix, overheating the exhaust. You can beleive what you want Hsmartash, but it is fact. 2500 RPM in 5th is a good combination of HP and torque when pulling grades heavy, I have had to run in 4th at 2500 at 23K because of the long steep climb on the So bound interstate 5 known as the Grape Vine. The CTD can run at redline all day long if you want to waist the fuel.

 

[HBarlow]

RVPoser: Better check your warranty book again. I think you're wrong on your warranty as you are on everything else you posted here.

 

[RVTRKN]

Hsmartash: And as usual you are talking out your ash! I guess your a warranty expert now, along with being a DMV expert for every State, every State DOT expert, 4th Gen expert, (even though you don't own one) You have your head so far up your ash its starting to effect your brain. Its a good thing you have an auto behind your CTD. I think you've been under water to long in a submarine, it's time to come up for a breath of fresh air, you need it!

 

[AClayton]

I'm not taking anyone's side here at all... ... ... but I tow a heavy triple-axle toyhauler and to date, I have never needed to pull a grade at 2500rpms. If I find a grade that takes me down enough to require a downshift, I simply slow down and enjoy all of the power I would need to pull a freight train up that hill..... at 2200rpm's! Turning a CTD to 2500 is not going to hurt it, but why would anyone ever need to. That would be like revving a gas engine to the brink of redline.

I'm no engineer but I have the same basic driving style as Rusty demonstrated. Tow the load conservatively and if a downshift is required, I do it manually and I slow my speed down to where my CTD is loafing along at a comfortable rpm. In most cases, if a grade slows my truck down, that same grade will have several slower trucks or cars in the slow lane also... ..... and I just fall behind them and wait it out patiently. Just because our trucks have the power to pull a grade at 65mph @2500 in 'whatever' gear, doesn't mean you or I have to. My truck is important to me and I need to take care of it. It does not make me feel less of a man to be in the slowlane pulling a grade when some teenage minded guy next to me in the fastlane is blasting up blowing smoke and making noise! My truck is modded for towing prowess and it performs well, but like most 2nd gens, they don't have quite the cooling capacity as the 3rd and 4th gens.

These trucks are like tools: Take care of them by not overworking it and they will provide yrs of service.

Alan

 

[RVTRKN]

Ya I agree, with you. But I did state 22-2500 RPM. With my 3:73 gears I find it hard to regain my RPM vrs speed when a semi goes to pass another semi just a couple of miles an hour faster slowing everyone down. When I'm on Baker grade, it has three lanes and I will run 2500 in 5th to help in avoiding this. It's not a macho thing, I just want to keep a good speed 55-60 MPH. When running flat it's the same speed but at 1800 RPM in 6th. When in a State that allows a higher speed towing its 70 at 2050 RPM. Keep in mind it's my preference to run that way and will not hurt the CTD, but bogging the RPMS to try and save fuel, is not worth an engine rebuild.

 

[RonD]

I thought this was the 4th Generation section ?, not the 2007 section, you may want to make your posts in the proper section

 

[RVTRKN]

I answered a general question that pertains to 3rd and 4th gen. Your fearless leader, Hsmartash took us in that direction.