those tires are not helping the ride. they look great, but are pretty stiff side walls. what tires did you have on the silverado? stock factory tires are designed to ride smoother and quieter, part of the "sales" pitch.

 

I had the stock wheels and tires on the 2020 Silverado. The wheels and tires you see in the picture were on the truck when I picked it up. I like the wheels and tires, but would rather have a smoother ride.

 

First off, thanks so much to all of you on the forums who share your knowledge and information.

Second, I apologize to all those who are going to tell me that my question has been posed on the forum in some form or fashion at least 100 times. I am new to the forum and new to working on suspension systems. I have looked and read for days and at this point it is all starting to run together.

I just picked up a 2020 Sierra 2500HD SLT with 49,600 miles on it. I love the truck, but it rides like a horse and buggy. When crossing from a paved road to a concrete bridge, the slight rise in the surface will make the truck almost hop the rear wheels. A little background, In 2020 I bought a new 2020 Silverado 2500HD LTZ Z71, which is essentially the above truck's cousin. I loved that truck and the way it rode, but I sold it a couple of years later for some quick cash. The Silverado was all stock as it was brand new so I know what the stock ride feels like and I loved it. Recently to verify to myself what the stock ride should be, I test drove a new 2024 Silverado LTZ Z71 and it was just like the one I had in 2020. Both of those rides are far superior to what I am experiencing now in the 2020 Sierra 2500HD.

The Sierra 2500HD is running BFG AT KO2s at 35x12.5R20 E Rated. When I picked it up, the pressure was set to 70 in the rear and 65 in the front. As I wasn't hauling or towing anything at the time, I dropped the pressure down to 45 in front and rear as suggested several times on this forum. Still rides rough. From what I can tell, there is no leveling kit. My ground to fender and top of tire to fender measurements are below:

Ground to Fender in Rear - 41.75"
Top of Tire to Fender in Rear - 8"
Ground to Fender in Front - 40.50"
Top of Tire to Fender in Front - 7"

The truck still has Rancho shocks front and rear. I assume these are the original, but not certain. I thought maybe worn out shocks, but when I tried to bounce the rear and see if it kept bouncing (old school shock testing), the rear end stops immediately. I weigh 315 pounds, so it got a good shaking.

The previous owner added an air bag system to the rear. I am not sure what brand as I do not see any identification on it. The bags are currently completely deflated.

Does anyone have any ideas on what I can do to make this ride like factory again? I have ordered a new set of Bilstien 4600 shocks which should be in early next week as a start, but wondering if there might be something obvious to those with more experience. I got the 4600 as I don't tow much and no off roading and I prefer a smoother ride.

Thanks again! View attachment 1127003

If I had to guess I'd say it's likely due to the higher unsprung mass from the meatier tires.

 

Another vote that the source of the issue is the tire/wheel combo. Maybe see if your local dealer has a set of take-offs.

 

be glad it doesn't ride like a donkey or a jack ass.

 

No, expert here, but the first thing you are doing to junk those Rancho shocks and replace with Bielstein's is a great step. I replaced mine at 15K and 3 of 4 were completely gone. Every time I hit a bump in the road, it sounded like a 30.06 going off and felt like the bed was coming apart. Off the truck I compressed them and three never moved.
I replaced with 5100's and am mostly happy with them. They are a little stiff for me, so I wish I had gone with the 4600's the first time.

I'm not a fan of the big tires, but I am an old guy. So, I would second or third a move back to more factory style tires for a smoother kind of ride. JMO....

 

I have never used these, but those that have say they make a huge difference on the HD trucks ride quality (much more comfortable and less jarring) but…?

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They help but not as much as air ride.

2020+ GM 2500/3500 P/U 4-Link Rear Air Suspension

Get more done with one haul and enjoy the road while doing it by adding a Kelderman 4-Link Rear Air Suspension!

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Yea, a bit of a price difference there… holy $#@%, lol

 

Go check the ground to fender measurement on a stock 2020. Your measurements show a difference of 1.25” front to rear. Previous owner might have just cranked the torsion bar keys without adding any other leveling parts.

My 2018 has a ~3.5” difference front to rear stock. Not sure how much it changed for 2020+.

 

Ditch the bling tires and rims. Put stock or stock like shocks on it. After you intall the stocks rims and tires, set the ride height to specs. Remove the air susp system completely, even if it's empty it affects ride (it still has some air in it and will try to compress it on a bump) and it's extra unsprung weight.

 

Update:

Thanks to all of you for chiming in. Having multiple brains thinking about the situation is always helpful.

I would have never thought it at under 50K miles, but the Rancho shocks were trash. The one on the rear driver side still has not rebounded from when I took it off 24 hours ago. It was completely shot! I put the Bilstein 4600s on and that made such a huge difference. It now rides much more like the stock 2024 I test drove for comparison. I am not a fan of the big wheel/tire combo either, but they were on it when I got it. They look good on the truck and I don't want to spend $2k replacing with factory wheels and rubber. I will keep an eye out for a cheaper set to pick up.

I think you may be right on the torsion bar as well. It looks very close to level and there were no leveling kits when I replaced the shocks. I will have to do some research to find out stock ride height on this truck and see what setting it there does. Thanks for the tip.

Speaking of tips. Tip for those coming after with the same issue. Take a bit of time to pull the rear shocks. It really only takes about 30 minutes to pull both, at least on the 2020 -2024 GMC/Chevy. Once I did that, I could tell the shocks were blown and needed new ones.

The rear are a snap. The front are a bit more difficult. I would plan on either removing the wheel liner or make sure you have a 13/16 ratcheting wrench. The nuts on the top of the front shock are difficult to get to with a deep well socket. I actually could not change the driver side until I get the ratcheting wrench and that is with removing the wheel well liner. They have too many hoses in the way that prevent you from getting a socket on period. All in all, changing the shocks can be done in a couple of hours, even for a novice like me.

I am now happy with my purchase of both the truck and the new shocks.

 

Thanks for the update!

 

Glad you got it sorted out and happy with how things are set up now. Lot of us jumped at the wheel / tire combo but the shocks were definitely easy to verify and cheaper too.

 

UPDATE Just an update for those coming after this with similar issues. As mentioned before, I replaced the shocks, which I believe helped, some. I still wasn't satisfied as the truck still rode rough. I then decided to crawl under the truck and check the torsion bars. They were in fact cranked all the way up to level the truck. I lowered the front end about 1 1/2 inches by backing off on the torsion bars. This also helped a bit. Mainly in the roughness up front, but the ride was still a bit rough in the rear. Next, I decided to abandon the 35x12.50 KO2 tires that came on the truck as I had been reading they had a 3 ply sidewall and that could be contributing to the stiffness. I put on a set of good used Wrangler All Terrain TA tires of factory size. This helped more, but it sill felt a bit hard in the rear end. Running out of options, I decided the only thing I could do was see if the airbags it came with made a difference. I was running them at the lowest pressure, even at times with no pressure just to "eliminate" them from the ride quality. Well, as I thought about it I started realizing that the airbags may be limiting the suspension travel so I decided to remove them. After removing them, the ride quality was drastically different. I can only surmise that the airbags were not letting the rear end suspension fully travel down and thus was making the ride seem very stiff. I am now running with no airbags and no bump stops in the rear and it rides great. I guess the moral of the story is there may be more than one contributing factor causing the problem you are troubleshooting. If you have a ride quality issue, start with the cheap stuff and remove what you can like air bags to see how that affects the ride.

 

good job sticking with it until you have the ride you want. Now you can enjoy your truck.