Community Forums

Wh34t · 03-15-2025, 12:30 PM

I have a 2003 Chevy 1500HD and I use it to tow a 27ft, 7k lbs TT. When I am not towing the trailer the truck rides fine and I have no issues with it, but when we are loaded up and going down the road I get a nauseating amount of bounce from the road. It seems that the truck cannot settle once it is set in motion and just bobs up and down like a boat until the road flattens out again. I have had other tow vehicles and have never experienced this before. I had a mechanic check it out and they told me my leaf packs are just worn out, but I feel like that would be more noticeable when I am using the truck day to day. I want to know general opinions of whether or not I should replace the spring packs or if I should try adding air bag suspension to try and stabilize the problem. I use a WDH and the truck has very marginal sag when the trailer is fully loaded with water. The bouncing is really the only issue I have with the setup but it makes me feel sick after driving for a while.

d23haynes57 · 03-15-2025, 12:43 PM

Continuing motion after a road upset is really a job for the shock absorbers to control. You may be overloading the vehicle beyond what the shocks and the way that are mounted are designed to handle. What is the toung weight your trailer is placing on the back? Your truck may only have a payload rating of 1,400 pounds and a 7,000-pound trailer placing a 700-to-1.000-pound load on the back may be too much. I would go for a better-stiffer shock first.

CharlesinGA · 03-15-2025, 12:49 PM

Are you using a Weight Distribution Hitch???

I realize a 1500HD of that vintage is what is known as a "heavy half ton". GM made way too many 3/4 ton frames so the story goes, so they fitted them with smaller, lighter half ton components, such as smaller brakes, lighter springs, etc. You do have a stout frame however.

It sounds like your shocks are worn out. You are pushing the limits of the truck. A set of Timbrens would be a good investment, as they replace the bump stops and the axle must travel a half inch or so before it hits them. Everyone says they do a good job of dampening heavy loads and supporting them, but continual bouncing is a sign of shock failure.

One minute video on how they work.

https://youtu.be/ZyQlZxLQqZ0

Charles

Wh34t · 03-15-2025, 01:48 PM

Okay, I will look into the Timbrens as I have heard that recommendation before. I do use a WDH, I dont know the exact model but it's a Husky and it was set up by the RV dealer. The 1500HD is the same as a 2500 non HD as far as the suspension goes, and I get the 6.0/4L80e with a full crew cab and a long bed as well as 4 wheel disc brakes, so its honestly a nice package. I have like 2700lbs of payload or some ridiculous number like that, so I know I'm not overloading the rig. I replaced the struts all around about 2 years ago with these Yellow (at the time) Monroe 34690s (https://www.rockauto.com/en/moreinfo...&pt=7556&jsn=5). Are these not good enough HD struts? What would I replace them with?

d23haynes57 · 03-15-2025, 02:17 PM

Here are some options for shocks.
https://www.shockwarehouse.com/searc...0-HD/Drive/4WD
Look at the Bilstein B8 series.

Wh34t · 03-15-2025, 02:33 PM

Are the B8s really going to perform that much better? The truck had rancho RS5000xs on it when I got it, but they were blown out and leaking so I replaced them. And is there no possibility my leaf springs are just worn out and its not the struts?

d23haynes57 · 03-15-2025, 03:01 PM

I do not have experience with those Monroes but typically, they are value-based junk. The Ranchos may have worked well when new but as you found the guts don't hold up.
Some folks don't like the Billsteins complaining they are too stiff. They are a high-pressure gas shock offering really great rebound control. You can also look at the Fox shocks especially with the remote reservoirs and stuff. If this was my truck. no towing the Bilstein B6, for your situation, the B8. I am not a fan of adding suspension bump stops. I have done air bags with various levels of success. You stated ride height is good. You did not state anything about the suspension bottoming out. What size tires and wheels are you running? Passenger or real truck tires? Could be room for improvement there. If I was working on this for you I would focus on the shocks first.

Wh34t · 03-15-2025, 03:10 PM

Thanks a ton for the perspective! I'm still learning that you really do have to pay to play when it comes to buying components. I am running 10 ply Cooper Discoverer ATP IIs from Discount Tire. They're the factory 16" wheels, but I don't remember the exact dimensions and I'm out of town right now. I haven't had issues with Cooper tires in the past so I just went with them again because the price was right (got all 4 out the door for around $900).

d23haynes57 · 03-15-2025, 03:18 PM

Quote:

Originally Posted by Wh34t

Thanks a ton for the perspective! I'm still learning that you really do have to pay to play when it comes to buying components. I am running 10 ply Cooper Discoverer ATP IIs from Discount Tire. They're the factory 16" wheels, but I don't remember the exact dimensions and I'm out of town right now. I haven't had issues with Cooper tires in the past so I just went with them again because the price was right (got all 4 out the door for around $900).

You have a good tire. Going to a 20 or 22 wheel would take care of some of the tire induced bounce. Have check load capacities and stuff for fitment. My 22 Denali running factory 22 with 305/45-22XL tires. These are only 32". Steers like it's on rails, almost. Hankook RF12's.

CharlesinGA · 03-15-2025, 07:06 PM

I agree with Dennis, Monroe is just riding on their name, they are light duty crap.

I put KYB mono max on my RAM 2500, the original shocks were either leaking or totally worn out. The KYBs proved to be useless, and I installed adjustable Rancho 9000's and have been happy with them. A lot of people recommend the Bilstein's but I have no experience with them. You also should get the full instructions for your hitch and go through the setup from step 1. Dealers generally just throw them on and don't know how to set them up properly. Common complaint on RV forums.

Charles

CecilD · 03-15-2025, 10:56 PM

I would first try stiffening up your weight distribution hitch. If you are experiencing bouncing, the hitch ball joint is flexing. Check the weight of your WDH bars, I would recommend at least1,200 pound bars for a trailer that size. Shocks next.

Rhagfo · 03-16-2025, 07:27 AM

Quote:

Originally Posted by d23haynes57

Continuing motion after a road upset is really a job for the shock absorbers to control. You may be overloading the vehicle beyond what the shocks and the way that are mounted are designed to handle. What is the toung weight your trailer is placing on the back? Your truck may only have a payload rating of 1,400 pounds and a 7,000-pound trailer placing a 700-to-1.000-pound load on the back may be too much. I would go for a better-stiffer shock first.

looks like first answer is the best answer! So many overlook shocks as a solution to ride issues. I went with Bilstein shocks on our 2001 Ram 2500, as the OP stated normal driving they worked fine, when towing we would get about three cycles at bridge transitions, before going back to smooth ride. Once the Bil's were on that was like a 1/2 cycle back to smooth ride.

zrock2010 · 03-16-2025, 08:24 AM

The Timbrens are nothing but junk i had them on the same year of truck and when it was down on them it rode like crap not to mention they are basically a bump stop and your veh was never designed to ride on the bump stops its to hard on things. I agree with the above about shocks. Your spring are well past their prime if they have never been changed out but if your happy with the ride no point in changing them i would just add a set of airbags and be done with it.

kdauto · 03-16-2025, 10:25 AM

Quote:

Originally Posted by zrock2010

The Timbrens are nothing but junk i had them on the same year of truck and when it was down on them it rode like crap not to mention they are basically a bump stop and your veh was never designed to ride on the bump stops its to hard on things. I agree with the above about shocks. Your spring are well past their prime if they have never been changed out but if your happy with the ride no point in changing them i would just add a set of airbags and be done with it.

I disagree on the Timbren, been running them front and back on my old Suburban for 19 years. As to airbags, they work...until they puncture. Then they become a PITA and can be very dangerous if only 1 side goes. The vehicle was not desgned to be resting on airbags either. Timbrens are "one and done" I replaced my front set after 18 years as I lost one on the road, hardware probably rotted away.

The O.P. probably is running worn shock absorbers. Hard to comment on anything without pics or a vehicle present. We don't even know the wheelbase and build of the truck.