Another JR

3/4? That’s hefty!

Do you have camper springs or a plow package? That will make the front stiffer. Have you lowered tire pressure when unloaded? 60 psi will ride a lot nicer than 80. (The rear tpms alarm pressure on my truck is 62 psi.) Jettech was talking about the thickness of the four first-stage springs marked with the green arrow compared to the thickness of the second stage spring marked with the red arrow.

On my 2021 3500 hd cclb srw gas I measured the rear springs thicknesses as follows. This was done with a calipers and metal ruler and I feel I was accurate to the nearest 64th of an inch. I was measuring on the outside of the spring coatings, so take that into account. The primary springs are 3/8” thick, and the secondary spring is 9/16” thick. This was a p/n 84992006 spring assembly. My RGAWR is 7250 lbs.

It does look like yours is thicker. I’ll measure tomorrow so you can compare. I can see why they might have done that for the 2500 configurations that don’t have the third stage springs.

I have provided below my front wheel center to fender measurements for my stock 3500, but I don’t know if the 2500 had the same nominal target height. My guess is that it is intended to be set to the same ride height. These measurements were just done with a tape measure and are to the nearest 1/8 inch. The truck is empty, but it has a full fuel tank, which makes the left side sit slightly low. Left is 24.25 inches and right is 24.5 inches. It looks to me like your truck is at almost exactly the same height in front as mine so I suspect your torsion bar settings have not been changed.

The diameter of the 5600 lb spring is approximately 1 and 34/64 inch. The diameter of the 5200 lb spring is approximately 1 and 32/64 inch. Here are the front torsion spring part numbers from an MTU post a while back (left/right): 4400 FGAWR 84745473/5 4800 FGAWR 84745477/9 5200 FGAWR 84745481/3 5600 FGAWR 84745485/7 6000 FGAWR 84745489/91 I believe your rear leaf springs should be part number 84992005.

That’s the FGAWR rating I’d expect. To be thorough at diagnosing this from a distance, since you have already reduced tire pressure appropriately, I’d suggest next confirming you have the correct front and rear springs actually installed. I know it’s very very unlikely GM would install the wrong parts, but it’s easy to check. I have my original 5600 lb front camper springs in the garage and I have installed the base 5200 lb springs for my model. Later today I’ll put a caliper on them and post the torsion bar diameters. Yours should be smaller diameter than mine if they are actually 4800 lb springs. I’m suggesting this measurement method because my original factory springs didn’t have an obvious part number marking. The rear leaf springs have the eight digit part number painted on them in large characters on the bottom surface, but I don’t have the table showing part number versus model. The secondary spring gaps when the truck is unloaded should look like these pictures from Jettech’s 2500: If the gaps are much smaller like these pictures from my 3500, then you have the wrong springs unless you ordered the 3500 rear springs under an option I others have said is now available: If the springs check out, it may be that your shocks are overly stiff, or it may simply be that your expectations are for a softer ride than the truck provides. I know our 3500 gives a fairly stiff ride, especially in the rear seat, but it’s not horrible. I still have my original Rancho shocks, so I’m hoping for a little improvement when I eventually replace them.

The front torsion springs are different for different truck configurations based on the front axle load. Do you have a plow package or camper springs? What is the FGAWR on the door sticker?

I load and unload my Four Wheel Campers pop up slide in camper about three or four times a year. If I am going to have it off the truck for only a month or two, I just drive the truck with no tailgate unless there’s some hauling that requires it. My tailgate mostly lives sealed in the padded crate except for the long winter stretch when I have the camper off from late October to early March.

I know you are talking about the braking features, but I’m wondering if you have the vibrating seat warning or just the chimes and red HUD bar.

Yes, the cables are the stop and the load path. Without them, the mass of the tailgate, even with the torsional assisting spring, would cause it to find a “new” stop every time your truck bounces. That might be loading the hinges, hitting the sheet metal on the bumper, or whatever tries to stop it from going down first. This is a two-man tailgate. It weighs 75 lbs and is too big to get your arms around. If you ever were able to remove or install it yourself I’m impressed.

Pictures for Jettech These are my 3500hd cclb gas srw springs showing the secondary spring gaps with the camper off and the truck empty.

You will find a lot of nearly new 20” takeoff wheel sets in various styles from these trucks on Craigslist. Personally I think 18s are a much better choice.

Maybe it’s just me, but I can’t access the video.

The 2022 and on have a procedure you can follow to lockout the opening of the inner tailgate. The procedure is in the owners manual and has you hold the inner tailgate button down for 3 seconds with certain preconditions. Repeating the procedure reactivates the inner tailgate. This feature is not on 2021 and earlier trucks. There are also some aftermarket lockout mods based detecting the presence of a ballmount in the receiver and they involve splicing into a wire bundle.

You too could have those springs if you order your new fancy 2024 with the 10 speed and the big screen as a 3500.

The OP hasn’t visited the site since March of 2022. If you quote him and re-ask the question he should get an email that you quoted him.

I’ll take pictures again when I take the camper off in a few weeks.

It is apples to apples. I’m not guessing at the unloaded suspension position. I had taken careful measurements of my rear suspension (wheel center to fender to eliminate tire effects) when it was unloaded, and I today put it in the same unloaded position by jacking the frame up to unload the rear suspension to the unloaded suspension measurement. It doesn’t matter how the static suspension position is achieved. It just needs to be in the same position as the unloaded position to show the spring gaps for that suspension position. The truck could literally be upside down and it still would show it correctly (other than the small gravity pull on the springs themselves ever so slightly changing the spring shape).

Exactly level laterally. Front wheels lower than rear maybe 2 inches. Camper still on, but truck frame (not rear axle) is jacked up by the about 1.5 inches needed to put the rear suspension at the unloaded extension exactly as previously measured from wheel center to fender last time the camper was off with 1/4 tank of gas in the truck. I had taken those measurements to see exactly how much the camper settled the rear suspension. The truck rear suspension in those pictures is at exactly the unloaded rear suspension extension, and the 1.25% slope of the driveway has no effect.

The rain stopped so I finally got my truck out to take pictures. At the unloaded position of my rear axle as shown in the attached pictures the secondary springs have a little clearance (1/8 at front and 3/8 at rear, roughly), which is much less than the large clearance shown in your pictures. The secondaries are in full contact by the time the suspension is depressed 1 inch from the unloaded position.

It’s an air bladder isn’t it? I suspect it leaks down through an imperfect check valve.

Yeah I like ordering a vehicle so nobody test drives it and abuses the brand new engine. My truck had 2 miles on it when I took delivery.

There are a lot of tire diameter calculators on line that would allow you to evaluate alternative sizes to verify the overall diameter is very close.

Here is a picture of my homemade camper camera enclosure made from a pvc pipe fitting. Camera itself was $90, cable $10, fittings $6.