Not IMO. I drove both types of SRW 3500's before ordering my 22 2500. But I will admit that pretty stiff is subjective. Both types of 3500's unloaded would skip over expansion strips and could get a little squirrelly in rough corners. That does not happen with my 2500's, even running 60-70psi in the tires. Note that I live in the Ozark Mts, where our roads are mostly narrow-ish and twisty. It was a pretty stark difference compared to my 18 2500 with factory air.
That’s not something I’ve ever experienced, with or without auto-level, on narrow and rough roads.
My point is that both ride much stiffer than a 2500 with factory air. There may be some ride difference unloaded with 3500's, but it sure was not noticeable on test rides.
I don’t have any time in a 2500 with air, but I do have some miles in a 1500 with air and even then the 3500 with air is not much stiffer than the 1500. The 3500 with air does ride better over rough roads than a standard spring 1500.
Don't they sit on the same leaf springs either way?
No, not even close. I figured you assumed this based on your comments.
The SRW standard spring suspension uses the same main 3/1 leaf pack that is used on the standard spring suspension DRW, but without the upper overloads. This is a fairly stiff spring pack.
The auto-level trucks have two full length leaves as the main leaves, these are fairly soft and provide a very comfortable ride empty. Very little air is kept in the bags empty at normal ride height as I only get about 3/8” drop going into bed lowering mode. This all makes for a fantastic ride on a 3500, better than any other HD truck I’ve ridden in, which is all the brands/options except the 2500 auto-level.
But, that’s not even the best part of the 3500 auto-level. Sitting below the softer main leaves are the overloads, which is one full length leaf and one half leaf on the front half. Unlike most lower overloads these are engaged with a fairly large rubber nipple that keeps contact from being abrupt as the suspension cycles in normal height. When you have sufficient payload, 500-750lbs is what is generally takes, then alternate ride height will drop the rear of the truck onto these overloads. These overloads do a great job a helping support heavy payloads and provide additional lateral stability in corners.
In bed lowering mode, no air in the bags, 2000lbs over the axle will lower the tailgate height by 2”. The main leaves lower pretty quickly onto the overloads as weight is applied, but then the rate of squat slows on the overloads. The standard springs have a rating of 2800lbs/in, which means they likely would deflect less than an inch with the same load (but I haven’t measured it in real life).
Oh, it does. Quite a bit better. But If I had towing loads that exceeded the 2500's capacities, I'd have gone 1 ton anyway.
How heavy have you gotten? I’ve read more than a few accounts of the 2500 air suspension giving an overload message without being all that heavy.
If you ever did find the air suspension couldn’t keep up with your load it would be pretty easy to supplement the factory suspension with airbags. The airbags would let the OEM system do its thing without overloading, and provide additional lateral stability due to their outboard location.
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He is somewhat abrupt with his descriptions...
