Community Forums

smurfsofwar · 05-15-2016, 09:42 AM

I thought the 2000lbs or so limp mode was only on the 1500?

Bob1340 · 05-15-2016, 09:49 AM

Quote:

Originally Posted by harleyjt

Not really. The 3500 has a heavier frame. Rear axle may be the same but carries duals. (I think there is still a SRW available but obviously with reduced capacity). I'm almost certain both use leafs. Coils are only used in the 1500.

jt
2005 Newmar Kountry Star gas 3742, Workhorse 8.1L w/Allison 5 speed.

Sent from my iPhone using iRV2 - RV Forum

All the heavy duty trucks have the same frame with the only difference being in wheelbase. The Dually has a different axle as it uses dual wheels. But the guts are the same I think, definitely the same on the SRW which we are talking about here. But whatever weight will bend up the lightest gvw 2500 will also taco the frame on the heaviest 3500 Dually.

archer75 · 05-15-2016, 11:38 AM

Quote:

Originally Posted by smurfsofwar

I thought the 2000lbs or so limp mode was only on the 1500?

My diesel payload is about 2300lbs. The 1500 is down around 1000lbs give or take.

smurfsofwar · 05-15-2016, 12:22 PM

Quote:

Originally Posted by archer75

My diesel payload is about 2300lbs. The 1500 is down around 1000lbs give or take.

Yes but in the 1500 series many users report the air suspension doesn't go into protection mode until around 2000lbs. Well over the stated payload, but still operates up to that number. I would have thought the HD class trucks would have a far higher threshold.

Bob1340 · 05-15-2016, 01:41 PM

Quote:

Originally Posted by smurfsofwar

Yes but in the 1500 series many users report the air suspension doesn't go into protection mode until around 2000lbs. Well over the stated payload, but still operates up to that number. I would have thought the HD class trucks would have a far higher threshold.

Correct. I don't know where the 2500 goes into limp mode, but it works similar to the 1500 system. If overloaded it tells you it's over heated and shuts down. But all in all the 1500 and 2500 Auto Level systems are different animals. the 1500 has it on all 4 corners and the 2500 has it on the rear only. The 3500 system differs from the 2500 in that it is an assist system and only has one height mode. The 3500 has leaf springs. The 2500 to my knowledge has no springs. I've never seen the guts of it as it's covered up.

One of these days I need to do a test on mine and see where that threshold is. My payload is 2800 lbs and I'd like to put like 3,000 in the bed and see what happens. And I wonder if the threshold for a 6.4 Hemi and the CTD is the same? I know the cargo capacity is much less on a CTD than the gas engine but I'd think the auto level system is the same.

I'd just as soon not have it. I really liked this truck when I bought it and the price was amazing. But in retrospect I'd of rather not have the auto level. When I bought it I figured I could just remove it and install some coils and air bags----not! You'd have to get a different computer and all sorts of stuff to remove the system. At $1500 for an option it is silly. Air Lift has really good long lasting stuff you can buy at a fraction of that.

archer75 · 05-15-2016, 01:50 PM

The 2500 has coils. Well without the airbags. I would have thought the airbags would have been in addition to the coils. Payload seems to be about 500lbs different between gas and diesel. But some aftermarket airbags should increase that substantially.

cwsqbm · 05-15-2016, 01:54 PM

Quote:

Originally Posted by Bob1340

Not true. That 1" think is in reference to the two different ride heights available. Standard height which would be like a regular truck. The second height is about 1"-1.25" lower and this is called Alternate tow height. But regardless if you drop 300 lbs or 1,000 lbs in the bed it comes back up to which level you have it set to. Now if you go over the load capacity of the system it'll go into a limp mode. That means it shuts down and you ride on the bump stops. This is why if you have a 2500 CTD with that 2000 lb load rate you may want to opt out of the auto level.

The system can handle a lot more than 2000 lbs. Consider that the rear axle weight is basically the same regardless of whether there is a diesel or gas motor. The 2000 lb load limit is there for legal reasons (to stay under 10k), not mechanical ones.

smurfsofwar · 05-15-2016, 02:08 PM

Quote:

Originally Posted by Bob1340

One of these days I need to do a test on mine and see where that threshold is. My payload is 2800 lbs and I'd like to put like 3,000 in the bed and see what happens. And I wonder if the threshold for a 6.4 Hemi and the CTD is the same?

It would be interesting to see the results of that if you ever do it.

Bob1340 · 05-15-2016, 02:19 PM

Quote:

Originally Posted by archer75

The 2500 has coils. Well without the airbags. I would have thought the airbags would have been in addition to the coils. Payload seems to be about 500lbs different between gas and diesel. But some aftermarket airbags should increase that substantially.

I have a 4X4 Mega Cab with the 6.4 gasser, the sticker on the door says 2800 lbs. A guy who drops his kids off at the same school I drop off my grandson has a virtually identical truck in the CTD version. His label is 1935 lbs. My truck would be 2900 lbs but I have a lot of options on mine which drop that number down. I've looked at 2016 models at the dealer ship equipped similar to mine with stickers in the 1800 lb range.

Quote:

Originally Posted by cwsqbm

The system can handle a lot more than 2000 lbs. Consider that the rear axle weight is basically the same regardless of whether there is a diesel or gas motor. The 2000 lb load limit is there for legal reasons (to stay under 10k), not mechanical ones.

True, but being the CTD is about 1,000 lbs heavier than a 6.4 it reaches that limit a lot quicker. This why I wonder if the Auto Air is different as the CTD has that extra weight up front. The rear wheel weight on empty trucks would probably be close to the same, maybe 3-4 hundred difference. But when loading the GVWR will be reached a lot quicker on a CTD as it's already 1,000 heavier than a gasser from the get go. If you look at it legalistically a lot of 2500's with the CTD could only hitch up to some of the smaller super light 5th wheels! Most have a cargo capacity between 1850-2200 lbs. Once you figure in the FDP (Fuel, Dogs, People) you ain't left with much. I am guessing to stay within the legal parameters the factory has the Auto Air system's computer set by the individual vehicle's load capacity. I ain't saying it is set to the door sticker weight but they probably program the computer off that number. IE, a fully loaded Limited 4X4 CTD long bed crew cab system would be programed different than a Tradesman single cab gasser long bed. A huge difference in the weight of these two trucks but the same gross weight rating. Just a hunch.

Bob1340 · 05-15-2016, 02:24 PM

And when you use the argument that the diesel's rear axle and tires can handle a lot more than that you are tossing out the legalistic aspect of the scenario. (which I like!) So as long as you are okay with tossing out the legalistic parameters just put a set of good air bags on that 2500 and call it a 3500 srw as the components are the same. People have done that for years with 2500's.

dmstepa · 05-15-2016, 04:08 PM

Quote:

Originally Posted by archer75

The frame is also the same between the 2500 and 3500.

I have a 2015 2500 and I was checking out a 2016 3500 if my 5th mounts would work and the mounting holes are not there! So, the frame on the 3500 is different that way than a 2500. Couldn't say about tensile strength of the frame though.

gtsum2 · 05-15-2016, 04:55 PM

Quote:

Originally Posted by dmstepa

I have a 2015 2500 and I was checking out a 2016 3500 if my 5th mounts would work and the mounting holes are not there! So, the frame on the 3500 is different that way than a 2500. Couldn't say about tensile strength of the frame though.

Likely because the one you looked at didn't have the factory fifth wheel prep

Bob1340 · 05-15-2016, 09:20 PM

Quote:

Originally Posted by dmstepa

I have a 2015 2500 and I was checking out a 2016 3500 if my 5th mounts would work and the mounting holes are not there! So, the frame on the 3500 is different that way than a 2500. Couldn't say about tensile strength of the frame though.

LOL. It didn't have the holes drilled I wager. The fifth wheel prep to my knowledge is not a dealer add on. Factory only. I bet if you look up the part #'s the factory pieces are the same. Heck, the holes ain't cut out in the truck bed either.

Bob1340 · 05-15-2016, 09:38 PM

There's a RAM website someplace showing the frame specs etc. the thickness of the rails is the same. You can look up part #'s on axles etc and come up with the same parts for the 2500 as the 3500's. What is a wonder is how many different rear shocks they show. It's confusing.
To the OP. My advice is, buy a RAM. I've had many wonderful Dodge/RAM trucks since 1974. They are just really good trucks and you'll not regret firing up that big Cummings and backing up to your home on wheels. It'd do you well. Just forget about that auto level. It's an expensive option that'll give you issues down the road. Spend your cash on the rear cameras, both back up and bed view. I would not hesitate in getting the 3500 with the Aisin. Get the 4X4 as if for no other reason it has better trade in. I never thought I'd want a Mega Cab, but I'll never get anything else from now on. And once you make the wise decision to get the superior RAM of your choice, buy a cab filter for it. $35-$40 and it'll save your $$$$ once you get to 60k miles.
RAM RAM RAM.