skyhammer wrote: Also with the new max tow package that you can get with the HO engine, Dodge upgraded the AAM 4:10 rear axle with larger bearings and a stronger LSD.
First I have heard of a stronger LSD as there would be no need for it. The Max tow package did give you a new rear-axle pinion, new helical gears, upgraded bearings, and finned aluminum differential cover though. Dodge has always had stronger bearings and axles on the 11.5" AAM compared to the GM version of the 11.5" AAM.
Where do you guys get your information in the bearings, and the axles?
There is nothing about it on the AAM website.
The only production difference the magazines list is the ABS tone ring on the Dodge version, whereas the GM version does not have this.
No, there is another important difference! It is a MAJOR factor when servicing the differential!
For the GM guys, if changing rear diff oil (or the cover), ask the part store guy for a cover gasket for a same-year Ram 3500. The GM spec gaskets are paper, Dodge uses a steel-cored neoprene rubber gasket that is much less leak-prone.
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Quote: Dodge came in a far 3rd.
I'm a Dodge owner, and well, that disappointed me.
Motortrend badmouthed the Cummins engine, saying it had to work harder towing their 12,000 pound trailer than the GM or Ford diesel.
It has 800 ft/lbs of torque. Why is this happening?
Also the mileage comparisons were quite distinct. The 1 ton ram was about 2-3 mpg lower than the Ford and GM diesels in their testing analysis.
IMHO Dodge ruined the flat as a table top torque curve engine by trying to play keep-up.
Look at the perfect torque curve of the old engine and then look at the new sucky H.O. one.
One thing to look forward to is when Cummins goes urea. I think you will see a BIG change in the torque curve (think flat again) when they do. It's really hard to keep the Cummins clean without urea. At least as clean as the tree huggers want. That will all change when they start using urea (in pickups).
Same way with the mileage. It will all change for the better when Cummins goes to urea.
Why are you apposed to having the torque rise as the engine slows down? Seems like a plus to me. If the engine torque rises as the truck starts climbing a hill the truck will be able to better manage the hill.
When I pull hills with my Cummins it sure the hell isn't running at 1600 RPM try 2300-3000. Any lower RPM and the thing is a turd and drops speed fast. How is a torque curve that peaks at 1600 then drops better than one that peaks at 1600 and is flat till it defuels?
The reason you can pull the hill better at 2300 to 3000 rpm is because your engine is making more HP at that rpm. So if you start up a hill at 60 mph and your engine is producing its max HP of say 350 HP and is running at say 3000 rpm, it means that the engine is producing exactly 613 ft lbs of torque at 3000 rpm. Assume the hill is too steep for the truck to maintain 60 mph so the truck starts to slow down. Consider two different engines capable of 350 HP at 3000 rpm. One engine has a torque curve that builds as the engine slows and the other is flat. Obviously the engine who's torque rises as the engine slows down will not slow down as much as the engine with the flat torque curve. For instance say the truck slows down to 50 mph and 2500 rpm. the engine with the perfectly flat torque curve is now making 292 HP and still 613 ft lbs of torque. The one that has a rising torque curve is making say 680 ft*lbs of torque and 324 HP. If 324 HP is just enough to pull the load up the hill at 50 mph the truck will hold that speed but the engine with the flat torque curve will continue to slow down.
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SoCalDesertRider wrote: The Cummins is already using urea in the 4500/5500 cab/chassis truck and has been since 2010 I think was the year. You only need to look to the cab/chassis trucks to find out what the Cummins already does on urea. 305 hp and 610 lb-ft is the output of the cab/chassis 6.7. Dodge gives the cab/chassis with the automatic and 4.88 gears a 30,000 lb GCWR. It's 26,000 with the manual transmission.
Poor comparison, that motor is derated for commercial work.
SoCalDesertRider wrote: The Cummins is already using urea in the 4500/5500 cab/chassis truck and has been since 2010 I think was the year. You only need to look to the cab/chassis trucks to find out what the Cummins already does on urea. 305 hp and 610 lb-ft is the output of the cab/chassis 6.7. Dodge gives the cab/chassis with the automatic and 4.88 gears a 30,000 lb GCWR. It's 26,000 with the manual transmission.
It will do more hp and torque in a light duty application on SCR / DEF.
The decline in output to account for the duty cycle is roughly similar to the drop in Ford 6.7 output between the light duty and medium duty F 450.
Cummins runs out of emission credits in this coming model year (they are currently non-compliant, but have banked emission credits.
When they run out of credit, their choice is to pay the fine per unit, or implement an emissions strategy that brings it into compliance, or cease to market the engine.
Quote: Dodge came in a far 3rd.
I'm a Dodge owner, and well, that disappointed me.
Motortrend badmouthed the Cummins engine, saying it had to work harder towing their 12,000 pound trailer than the GM or Ford diesel.
It has 800 ft/lbs of torque. Why is this happening?
Also the mileage comparisons were quite distinct. The 1 ton ram was about 2-3 mpg lower than the Ford and GM diesels in their testing analysis.
IMHO Dodge ruined the flat as a table top torque curve engine by trying to play keep-up.
Look at the perfect torque curve of the old engine and then look at the new sucky H.O. one.
One thing to look forward to is when Cummins goes urea. I think you will see a BIG change in the torque curve (think flat again) when they do. It's really hard to keep the Cummins clean without urea. At least as clean as the tree huggers want. That will all change when they start using urea (in pickups).
Same way with the mileage. It will all change for the better when Cummins goes to urea.
Why are you apposed to having the torque rise as the engine slows down? Seems like a plus to me. If the engine torque rises as the truck starts climbing a hill the truck will be able to better manage the hill.
When I pull hills with my Cummins it sure the hell isn't running at 1600 RPM try 2300-3000. Any lower RPM and the thing is a turd and drops speed fast. How is a torque curve that peaks at 1600 then drops better than one that peaks at 1600 and is flat till it defuels?
The reason you can pull the hill better at 2300 to 3000 rpm is because your engine is making more HP at that rpm. So if you start up a hill at 60 mph and your engine is producing its max HP of say 350 HP and is running at say 3000 rpm, it means that the engine is producing exactly 613 ft lbs of torque at 3000 rpm. Assume the hill is too steep for the truck to maintain 60 mph so the truck starts to slow down. Consider two different engines capable of 350 HP at 3000 rpm. One engine has a torque curve that builds as the engine slows and the other is flat. Obviously the engine who's torque rises as the engine slows down will not slow down as much as the engine with the flat torque curve. For instance say the truck slows down to 50 mph and 2500 rpm. the engine with the perfectly flat torque curve is now making 292 HP and still 613 ft lbs of torque. The one that has a rising torque curve is making say 680 ft*lbs of torque and 324 HP. If 324 HP is just enough to pull the load up the hill at 50 mph the truck will hold that speed but the engine with the flat torque curve will continue to slow down.
What? That makes no sense at all.
If that cummins held its peak torque of 800 all the way till it defuels it would pull better, PERIOD..
The Cummins is already using urea in the 4500/5500 cab/chassis truck and has been since 2010 I think was the year. You only need to look to the cab/chassis trucks to find out what the Cummins already does on urea. 305 hp and 610 lb-ft is the output of the cab/chassis 6.7. Dodge gives the cab/chassis with the automatic and 4.88 gears a 30,000 lb GCWR. It's 26,000 with the manual transmission.
Quote: Dodge came in a far 3rd.
I'm a Dodge owner, and well, that disappointed me.
Motortrend badmouthed the Cummins engine, saying it had to work harder towing their 12,000 pound trailer than the GM or Ford diesel.
It has 800 ft/lbs of torque. Why is this happening?
Also the mileage comparisons were quite distinct. The 1 ton ram was about 2-3 mpg lower than the Ford and GM diesels in their testing analysis.
IMHO Dodge ruined the flat as a table top torque curve engine by trying to play keep-up.
Look at the perfect torque curve of the old engine and then look at the new sucky H.O. one.
One thing to look forward to is when Cummins goes urea. I think you will see a BIG change in the torque curve (think flat again) when they do. It's really hard to keep the Cummins clean without urea. At least as clean as the tree huggers want. That will all change when they start using urea (in pickups).
Same way with the mileage. It will all change for the better when Cummins goes to urea.
Why are you apposed to having the torque rise as the engine slows down? Seems like a plus to me. If the engine torque rises as the truck starts climbing a hill the truck will be able to better manage the hill.
When I pull hills with my Cummins it sure the hell isn't running at 1600 RPM try 2300-3000. Any lower RPM and the thing is a turd and drops speed fast. How is a torque curve that peaks at 1600 then drops better than one that peaks at 1600 and is flat till it defuels?
The reason you can pull the hill better at 2300 to 3000 rpm is because your engine is making more HP at that rpm. So if you start up a hill at 60 mph and your engine is producing its max HP of say 350 HP and is running at say 3000 rpm, it means that the engine is producing exactly 613 ft lbs of torque at 3000 rpm. Assume the hill is too steep for the truck to maintain 60 mph so the truck starts to slow down. Consider two different engines capable of 350 HP at 3000 rpm. One engine has a torque curve that builds as the engine slows and the other is flat. Obviously the engine who's torque rises as the engine slows down will not slow down as much as the engine with the flat torque curve. For instance say the truck slows down to 50 mph and 2500 rpm. the engine with the perfectly flat torque curve is now making 292 HP and still 613 ft lbs of torque. The one that has a rising torque curve is making say 680 ft*lbs of torque and 324 HP. If 324 HP is just enough to pull the load up the hill at 50 mph the truck will hold that speed but the engine with the flat torque curve will continue to slow down.
What? That makes no sense at all.
If that cummins held its peak torque of 800 all the way till it defuels it would pull better, PERIOD..
Sure it would but if it was able to maintain 800 ft lbs all the way to 3000 rpm than it would be making 457 HP at 3000 rpm. So what do you want to compare? Two engines of similar HP with different torque curves like I described - or a 400 HP engine to a 460 HP engine?
summithmk wrote: Did I once mention anything about horsepower? An engine with a flat torque curve will pull better.
A 460 HP engine with a flat torque curve will pull better than a 400 HP engine with a torque curve that rises as the rpm's decrease but if both engines have similar HP ratings the one with the rising torque curve will pull better.
skyhammer wrote: Also with the new max tow package that you can get with the HO engine, Dodge upgraded the AAM 4:10 rear axle with larger bearings and a stronger LSD.
First I have heard of a stronger LSD as there would be no need for it. The Max tow package did give you a new rear-axle pinion, new helical gears, upgraded bearings, and finned aluminum differential cover though. Dodge has always had stronger bearings and axles on the 11.5" AAM compared to the GM version of the 11.5" AAM.
Where do you guys get your information in the bearings, and the axles?
There is nothing about it on the AAM website.
The only production difference the magazines list is the ABS tone ring on the Dodge version, whereas the GM version does not have this.
No, there is another important difference! It is a MAJOR factor when servicing the differential!
For the GM guys, if changing rear diff oil (or the cover), ask the part store guy for a cover gasket for a same-year Ram 3500. The GM spec gaskets are paper, Dodge uses a steel-cored neoprene rubber gasket that is much less leak-prone.
Us GM guys don't need a gasket to change the diff fluid.
Our axle has a drain plug.
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