Bounce on Concrete Hwy's and Ride Rite?

[frenchsquared]

I have a 2018 Regular Cab, Short Bed 4x4, max towing. I love the truck and it rides great stock, so this isn't a GM issue. My job has recently changed and I am pulling a trailer about 400 miles a week. Its to the point I seldom even drop the trailer.  I added a ride rite kit to keep the rear of the truck at the factory position. I like seeing over the hood and I like my head lights aimed properly. The kit makes the truck ride better and steer better when loaded. Im hauling trucks from an auction back home to sell. Typically, I am loaded with a 4 door 4x4 F150. This are not light loads. However the truck has plenty of power, tranny doesn't get warm and simply does a great job unless...

 

Unless, I am on a concrete highway and empty. The bounce is terrible and dangerous. I am regularly turning my flasher on and pulling over to stop the bounce. Its like a death wobble but focused on the rear bouncing up and down. There is a rhythm created between the wheel base of the truck and the trailer that is cause this. Without a seat belt on you would hit your head on the roof. Really. My wife and I go way out of route to avoid concrete roads. When on them I have to run over 90 MPH to control the bounce or under 30. Both are not safe and terribly irritating. 

 

Has anyone got any ideas to stop the bounce or control the bounce when the trailer is empty or the truck is not attached to the trailer and there is any amount of air in the bags.  If there is no air in the bags the bags rattle as they kinda sit in place. If you add 1 lb of air to stop the rattle the bounce happens. With an empty trailer or with no trailer. 

 

Dual shocks? Different shocks? leaf spring clamps? shocks on trailer? Need some ideas other then buying another truck as I just bought this one. 

[TXGREEK]

I have a 2018 Regular Cab, Short Bed 4x4, max towing. I love the truck and it rides great stock, so this isn't a GM issue. My job has recently changed and I am pulling a trailer about 400 miles a week. Its to the point I seldom even drop the trailer.  I added a ride rite kit to keep the rear of the truck at the factory position. I like seeing over the hood and I like my head lights aimed properly. The kit makes the truck ride better and steer better when loaded. Im hauling trucks from an auction back home to sell. Typically, I am loaded with a 4 door 4x4 F150. This are not light loads. However the truck has plenty of power, tranny doesn't get warm and simply does a great job unless...
 
Unless, I am on a concrete highway and empty. The bounce is terrible and dangerous. I am regularly turning my flasher on and pulling over to stop the bounce. Its like a death wobble but focused on the rear bouncing up and down. There is a rhythm created between the wheel base of the truck and the trailer that is cause this. Without a seat belt on you would hit your head on the roof. Really. My wife and I go way out of route to avoid concrete roads. When on them I have to run over 90 MPH to control the bounce or under 30. Both are not safe and terribly irritating. 
 
Has anyone got any ideas to stop the bounce or control the bounce when the trailer is empty or the truck is not attached to the trailer and there is any amount of air in the bags.  If there is no air in the bags the bags rattle as they kinda sit in place. If you add 1 lb of air to stop the rattle the bounce happens. With an empty trailer or with no trailer. 
 
Dual shocks? Different shocks? leaf spring clamps? shocks on trailer? Need some ideas other then buying another truck as I just bought this one. 

If your suspension is stock then get yourself a pair of Fox 2.0 coilovers for the front $700-$800 which take the place of the garbage stock coil and strut. Bilstein 4600 for the rear. You’ll be thanking me


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[frenchsquared]

Completely stock at this point. However, I have a leveling kit and a drop kit sitting in the garage. Changed my mind. I jsut have not installed the leveling kit because of the tires. Im driving so much I want to use the factory tires before buying new ones. 

 

So, you think new front struts would effect the bounce in the rear? 

[Centex14]

Rear shocks will but really you’ve got about the worse combo to be towing with. A reg cab short box 4wd has absolutely no weight or leverage to counteract the bounce. I’d recommend more trying to get some weight off the truck and more centered over the trailer axle. Sounds to me like you’ve got to much tongue weight. Your air bags may not be helping any either. Just because they keep the truck level when loaded doesn’t mean they are helping. These trucks come with a rake in them for a reason and if the weight you are pulling is causing the rear end to sag so much that you are having trouble seeing in front of you then you’ve got to much weight on the truck.

 

 

2014 z71 LTZ

Volant Intake

Borla Exhaust

Diablo

Bilstein 5100

Rough Country Level

 

[frenchsquared]

Its not to much weight. Truck has a 9600lb towing capacity. Trailer isn't long enough to change where the weight is, but the issue is empty not loaded. Truck rides great loaded. I need to be able to pull the empty trailer to the auction without bouncing off the road. The issue is not enough tongue weight. The trailer is about balanced and is pulling the weight off the truck when hitting the bumps in the road. This causes the bouncing. I need more weight. 

[1SLOW1500]

I agree higher end shocks would make a world of difference. However until you go pro it all input is a guess. I would assume rear is too stiff with little to no travel. So it bounces.

[pronstar]

Bounce is rebound.

Rebound is a function of the spring rate, and the shock’s ability to control it.

The factory setup should control rebound if the load is within the design parameters of the vehicle.

Either your shocks are toast, or you have too much tongue weight.

Another possibility is the air springs increase the spring rate beyond what your shocks are able to control. A good shock should help here, if this is the issue.


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[Centex14]

Its not to much weight. Truck has a 9600lb towing capacity. Trailer isn't long enough to change where the weight is, but the issue is empty not loaded. Truck rides great loaded. I need to be able to pull the empty trailer to the auction without bouncing off the road. The issue is not enough tongue weight. The trailer is about balanced and is pulling the weight off the truck when hitting the bumps in the road. This causes the bouncing. I need more weight. 

Tongue weight and total payload are separate items.

The fact it bounces empty instead of loaded tells me to much on the truck and not enough on the trailer. I’ve pulled a lot of bumper pulls in my life and I’ve never had one whether open or enclosed bounce a truck while empty to the extent you are talking about. Loaded yes but never unloaded.

Have you ever scaled the truck and trailer loaded and empty to see where all of the weight sits? Be interesting to see where everything sits.


2014 z71 LTZ
Volant Intake
Borla Exhaust
Diablo
Bilstein 5100
Rough Country Level

[catpartsman]

I’m going to say your wheel base is just the right length to hit the joints in the concrete road at the same time, causing this bad bounce. When the trailer is loaded, the additional weight is keeping the bounce at bay. When empty the bounce is there because there isn’t enough weight on the truck to keep the truck under control. On the next trip, find a spot you can pull over and stop then inspect the truck wheel base and joint spacing. I’ll bet money they are the same length or damn close.

I experienced this on my ‘01 Sierra I had when pulling a boat home from Wisconsin. The axles where spaced just right to hit every joint at the same time. It caused a serious bounce as well and we had to find an alternate route to get off the concrete road.

Concrete roads are notorious for this issue, especially when the company who paved it had their machine set wrong or didn’t know what they were doing. Paving with concrete is a very tricky thing and if not done properly can make for a very harsh ride when driving on it.

If what I’m saying here is accurate, the only way to fix this is get a longer wheel base truck or find an alternate route to avoid the concrete road.




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[garagerog]

OP,  the problem with concrete highways are they are segmented with expansion joints, once your unloaded trailer hits that first expansion joint it's going to bounce and start the oscillation bouncing you describe between the 30-90 mph you mentioned. It's my belief that any suspension changes you make to your truck would have minimum benefit, the problem is with the unloaded trailer. If there is not a significant amount of weight you can shift from the tow vehicle to the trailer, you're going to have to address the trailer suspension. Trailer shocks like you mentioned might help, there are also trailer suspension equalizers, check out e-trailer.com. But before you spend any money at all, try lowering the trailer tires psi to the lowest safest psi and see if that helps, you'll have to carry a 12V compressor to air up before loading one of those F-150's.

[Centex14]

Have you tried playing with the pressure in your bags to see if that makes any difference?


2014 z71 LTZ
Volant Intake
Borla Exhaust
Diablo
Bilstein 5100
Rough Country Level

[Mike GMC]

Does the bounce happen without the trailer as well, or just an empty trailer?

[frenchsquared]

3 hours ago, pronstar said:

Bounce is rebound.

Rebound is a function of the spring rate, and the shock’s ability to control it.

The factory setup should control rebound if the load is within the design parameters of the vehicle.

Either your shocks are toast, or you have too much tongue weight.

Another possibility is the air springs increase the spring rate beyond what your shocks are able to control. A good shock should help here, if this is the issue.


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How is empty to much weight? Truck has done in since it had 3 miles. Its at 9,000 miles now. Its not worn out. Truck has 9600lb capacity. I have a small tool box in the bed So weight in bed is around 100lbs. Im certain Chevy trucks can handle 1/96th of there rated pay load. 

 

 

[frenchsquared]

36 minutes ago, Mike GMC said:

Does the bounce happen without the trailer as well, or just an empty trailer?

Thanks for reading the post. The problem is how to stop the bouncing when trailer is empty. 

If the bags have any air at all the truck will bounce without the trailer. If the bags are totally empty and no trailer its pretty much fine. All RCSB seem to bounce some on concrete highways. Ive had a dozen or more but the bounce is manageable. 

If the bags are empty or pretty much any air pressure when the trailer is hooked up it bounces. Im fine running the bags empty when there is no load. But I have to find a way to make the 4 hour drive to the auction with an empty trailer and not arrive in pain from the bouncing. 

 

 

[wforrest08]

Put 600 pounds of weight in the bed of the truck above the rear axle and take it for a test drive. 

If that works transfer the weight to the towed truck on the way home. This is my fix for my leveled 2500HD pulling my 20ft car hauler empty. Might get by with 200-400 with a 1/2 ton? I use 50# sand bags.

 

If that don’t work strap 200 pounds to the trailer as far forward as possible. Old timer told me years ago the magic number for tongue weight is at least 200 pounds and I’ve found this to be true. Same deal throw the weight in the towed truck.

 

I’ll assume you have the right amount of drop on your hitch already since you seem to have a clue. It amazes me how many guys I see running down the interstate with the chains dragging cause the nose of the trailer is way to low or the trailer rear of the trailer is about on the ground because it’s at a 45 degree incline. Either one will change the tongue weight especially on a tandem axle.

 

I didn’t know that the Max Tow was an option on the SWB, guess I learned something new today.