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I found the truck I like but the axel ratio puts me right at the maximum tow limit for my boat. if the truck has an eight speed transmission can't you just drop down a gear or two in the manual shift mode? anyone out there pushing their tow limit to the max?
 

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Plenty of people are. But its not the engine or trans that cant handle the weight. Its other factors like Axle, suspension, etc.
 

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Plenty of people are. But its not the engine or trans that cant handle the weight. Its other factors like Axle, suspension, etc.
Plenty of people are. But its not the engine or trans that cant handle the weight. Its other factors like Axle, suspension, etc.
Matty,

I am still confused as to why the exact same half ton with a hemi has a large increase in both payload and towing. Same brakes, same frame, same tranny, same rear end (don't think you can get the 3.55 ratio in the hemi) & same suspension.....the absolute only difference is the engine and exhaust. Granted the ecodiesel is down on h.p., but makes more torque (not to mention more useable torque). It doesn't make sense to me why the ratings are lower.

Heck a hemi set up the same as my ecodiesel only difference is gear ratio ( I have 3.55 / hemi set up with 3.21, & for those that don't know, 3.55s are better for towing than the 3.21 in this comparison. ...so the 3.55 truck you would think has the edge in this comparison) the hemi has a better max towing and payload. Now the only thing I haven't found so far is weight differences between the engines. But even if the diesel weighs a couple hundred pounds more, there is still a larger gap in the capacities.

I'm not buying the derated numbers for this truck until someone can give me a clear answer.
Hope this didn't sound too abrasive. ...and I'm not targeting you matty, I just want some answer that actually gives a reason why there is a large gap in capacities.
 

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The acceptance of the new sae rating system has been a game changer for us. Now, a great deal of weight is given to performance rather than the structural failure point of the overall system. The Ed is is being seriously penalized for lack of neck snapping acceleration ability. Discounting a drag race up Davis dam, I think the capabilities are far higher than the ratings indicate.

Here are the main test methods trucks are now measured on as per J2807:

Cooling capability on a long highway upgrade modeled on the Davis Dam grade on Arizona SR 68;
Launch and acceleration performance on a level road and a 12 percent upgrade;
Combined handling performance – understeer and trailer sway;
Combined braking performance – stopping distance and parking brake-hold on grade; and
Structural performance for the vehicle and hitch or hitch receiver.
New calculations for trailer weight ratings: In addition to the performance standards, SAE J2807 also uses a specific set of assumptions to calculate maximum trailer weight ratings:

For light-duty full-size pickups (GVWR < 8,500 lbs.), SAE J2807 assumes that the tow vehicle includes any options with higher than 33 percent penetration;
It assumes there is both a driver and passenger in the vehicle, each weighing 150 pounds;
It assumes that tow vehicles also include up to 70 pounds of aftermarket hitch equipment (where applicable); and
For conventional trailer towing, SAE J2807 assumes that 10 percent of the trailer weight is on the tongue."

Ram 1500 ecodiesel
Longhorn cc lb 4x4
 

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I found the truck I like but the axel ratio puts me right at the maximum tow limit for my boat. if the truck has an eight speed transmission can't you just drop down a gear or two in the manual shift mode? anyone out there pushing their tow limit to the max?
And then some! There's a recent "towing heavy" thread on the other forum that has some pretty surprising accounts; short tows with an 18000# dump trailer, a 600 mile trip towing 9400# with 3 adults & trappings. This was on a limited with 355's. A couple of car haulers in the 8000# range. All reports were with totally satisfactory results. I wouldn't be the least bit deterred if you don't exceed axle ratings.
 

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The acceptance of the new sae rating system has been a game changer for us. Now, a great deal of weight is given to performance rather than the structural failure point of the overall system. The Ed is is being seriously penalized for lack of neck snapping acceleration ability. Discounting a drag race up Davis dam, I think the capabilities are far higher than the ratings indicate.

Here are the main test methods trucks are now measured on as per J2807:

Cooling capability on a long highway upgrade modeled on the Davis Dam grade on Arizona SR 68;
Launch and acceleration performance on a level road and a 12 percent upgrade;
Combined handling performance – understeer and trailer sway;
Combined braking performance – stopping distance and parking brake-hold on grade; and
Structural performance for the vehicle and hitch or hitch receiver.
New calculations for trailer weight ratings: In addition to the performance standards, SAE J2807 also uses a specific set of assumptions to calculate maximum trailer weight ratings:

For light-duty full-size pickups (GVWR < 8,500 lbs.), SAE J2807 assumes that the tow vehicle includes any options with higher than 33 percent penetration;
It assumes there is both a driver and passenger in the vehicle, each weighing 150 pounds;
It assumes that tow vehicles also include up to 70 pounds of aftermarket hitch equipment (where applicable); and
For conventional trailer towing, SAE J2807 assumes that 10 percent of the trailer weight is on the tongue."

Ram 1500 ecodiesel
Longhorn cc lb 4x4
Thanks for the response. That is a good explanation of why the ratings are lower.
A good friend of mine was asking about my ed as he has a 5 year old hemi and looking at the ed. I have owned hemi s and I flat out told him there is no comparison in throttle dropping performance. The hemi would leave the ed in the dust.....but I don't drag race my truck. It had plenty motor to get itself moving, and fuel mileage that his hemi could only dream about.!

So it sounds as if that's why the hemi has an Edge on towing. .....thanks again!
 

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Discussion Starter #7
Thanks so much to all that replied. I had a feeling it's a semi complex formula used when rating a trucks towing cap.
I'm rebuilding a 25' 7500 lb. boat/trailer. The truck I'm looking at is a limited edition 4X4 fully loaded but the rear end is 355. what if I had to change the gearing? because it's 4X would the front have to be changed as well? 99% of my towing will be relatively flat with the exception of a quarter mile 7% grade (for now). the thing that I fear, is after dropping two times more $ than any other vehicle in my life I don't like the way it tows.
 

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it's discussions like this that make me think truck makers need to provide more extensive information on what towing is like with it's vehicles, information like that speeds up someones buying decision, an important fact for the many truck brands out there.
 

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I wouldn't entertain changing rears. If it's even possible, the cost would probably be prohibitive. You're at a big advantage pulling a boat rather than a wind sail of a trailer. Most likely, your concerns aren't founded. The Ed isn't going to give you hotrod acceleration but will be adequate for normal driving habits in normal traffic especially on flat land. You may find an isolated negative towing report somewhere but 99% of owners towing have been well satisfied with their results. You're on the right track in you're op; if you find performance a little sluggish, the tow/haul mode will hold shifts a little longer & down shift a little quicker, although most don't find it necessary. I don't know what you're coming from but I can assure you, the European luxury car ergonomics of that beautiful limited & unbelievable fuel economy will quickly earn your forgiveness for not yanking that boat around like a fuel guzzling hd truck!! Stop worrying & enjoy your new truck.
 

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Just some suggestions:


Put Better (e-rated) Tires on you ED and run MORE PSI.


Upgrade your brake pads and maybe rotors.


Get a computer flash from www.GreenDieselEngineering.com for added power and better shifting. They are very experienced with VM Motori Diesels.


Get a good Weight Distributing Hitch system to balance truck and trailer.


Get rid of any extra weight items you DON'T NEED.


None of these things will officially change your vehicles GVWR but...
 

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Didn't see anything listed for our ram @ greendiesel. The grand Cherokee they have a tune for only brings the specs up close to our ram performance. Do you know of anyone that is using them for ram applications?
 

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Based off of the information Boocoodinkydow gave, I personally wouldn't change anything at first. It sounds as though the ed suffers from the lack of "go" compared to the hemi which is why the listed tow ratings are less. With that being said, the tires, rotors, brakes, suspension, & frame are the same as the hemi. Stopping the load should be no problem at all. The trailer should have brakes as well so that will assist you in stopping.

Now if you are drag racing a hemi up a wicked grade, you will most likely loose.....but who actually cares about that. I too have read about guys towing ridiculous amounts of weight and it sounds like the ecodiesel holds its own. However, I wouldn't go extreme often as the weak point will inevitably surface much sooner than expected. Based on what you want to tow, don't think you are in the ridiculous category. Heck you aren't far from its rated capacity.
 

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If all you're towing is 7500lbs you will be beyond fine. I had my 07 and 05 Ram hemi's at an steady 8000 lbs towing a camper all fall and a john deere 1010 with trailer combo weight was almost 7500 on the nose. My 07 had the 3:55's and my 05 had the 3:92's....neither of these set ups gave me issues at any stage of the game. With the torqe of the ED I surely would not be concerned with towing anything in those weight ranges because I know the Hemi's did it with ease. Just my two cents.
 

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The eco diesel struggles up the Davis Dam hot trailer tow test. This would be the limiting factor based on the cooling system capacity. Eisenhower pass in Colorado is also a very aggressive test for a truck pulling a load.

The Ram eco diesel is not using the Hemi radiator, Chrysler pinched a few pennies and used the smallest radiator in the Ram feasible.

We pulled 6000lb up Eisenhower pass at 65 F ambient. The truck pulled the load easy for the first 2-3 miles, then the coolant temps creeped up into the hot zone and the engine computer started cutting power until the vehicle speed had dropped to 50 mph. We were full throttle the entire grade.

If you are pulling on flat ground in normal weather, I doubt the truck will ever run hot and reduce output. If full power is available, the Ram should be able to pull 10,000 lb or more...whatever the chassis limit is.

FYI, we do have good things in the works for the ECO Diesel in terms of fuel efficiency, power, torque, less turbo lag and improved drive ability.
 

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I do not believe the towing capacities listed on the Ram web page as being even close to accurate for the ED. If you check the different trim levels and change the gear ratio, box size, and cab size, the tow capacities don't make sense. A Laramie with a CC/6.4 box/4X4 is rated 400 lbs less than the Laramie Longhorn or Laramie Limited. Changing the gear ratio has no effect? The same Laramie with the Hemi and 3.21 gears is rated 1050 lbs higher.
I call BS.
 

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The eco diesel struggles up the Davis Dam hot trailer tow test. This would be the limiting factor based on the cooling system capacity. Eisenhower pass in Colorado is also a very aggressive test for a truck pulling a load.

The Ram eco diesel is not using the Hemi radiator, Chrysler pinched a few pennies and used the smallest radiator in the Ram feasible.

We pulled 6000lb up Eisenhower pass at 65 F ambient. The truck pulled the load easy for the first 2-3 miles, then the coolant temps creeped up into the hot zone and the engine computer started cutting power until the vehicle speed had dropped to 50 mph. We were full throttle the entire grade.

If you are pulling on flat ground in normal weather, I doubt the truck will ever run hot and reduce output. If full power is available, the Ram should be able to pull 10,000 lb or more...whatever the chassis limit is.

FYI, we do have good things in the works for the ECO Diesel in terms of fuel efficiency, power, torque, less turbo lag and improved drive ability.
Very interesting. thanx for sharing the info.
 

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Discussion Starter #17
I decided to hold off for a bit, not because I don't think it will tow my boat, On the contrary, after reading what's been posted I feel totally comfortable I'm looking at the right truck. The one I was going to buy was WAY loaded, I just couldn't sleep, the thought I was about to pay that kinda money for a truck. all that electronic stuff would make me afraid to take it off road. I would probably choose hand crank windows if it was available (I'm just that kinda guy)
I was just curious... who needs a heated steering wheel?? My boat won't be ready 'till spring so I have time to read and learn.
Thank you so much for the reports.
 

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Im the guy who has pulled a combined truck and dump trailer weight of over 18,000lbs with my eco.

I also have towed the same weight with my 2010 RCLB Hemi.
I can tell you this the eco can outpull the Hemi with the 545rfe speed transmssion,an its not even close.
Same 18.000 lb loads,same road to the dump same everything.

I think the difference for the hemi would be the new 8 speed tranny,but I still would be worried about getting the load moving like the eco can do.

When I towed 18,000 with the hemi it took a lot of throttle to get it moving and I mean a lot,there is no power down low in a Hemi.

People say,the eco spends a lot of time in 7th gear when towing,the 3:92 rearend will help get it back in 8th.
My eco CC weighed the same as my 2003-2500 Hemi,the lower gears will help all the time.
Hope that helps a bit.
 
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