3500 continuous, rhythmic bounce on concrete highway

[JKSchnoo]

Thanks for everyone’s reply. Today I started regretting getting the 3500, but am seeing that people still have the bouncing on concrete with the 2500 too, both gassers and diesels. Airing down the tires doesn’t seem to help much with the concrete seams, and looks like my mileage is going down, but it’s only been a day.

I guess I’m just not sure what to do here. I wanted this truck for pulling a 30 ft TT around the country with wife and (soon to be in a month ) daughter. We will only be towing the TT a half a dozen times a year, and it will be my daily driver in between. Worried now that hundreds of miles on concrete highway could be a miserable/painful experience for the family.

 

[flan]

I'd say it's the roads. I hit sections of that on 81 North and South in PA.

Its bad in the dually and even worse when i'm pulling a trailer. At one point it was so bad I ended up slowing down to 35 mph. If I stayed at the speed limits I'd probably be off the road.

I was going to reply about the concrete sections of 81 in PA, the only times I’ve experienced “porpoising”. With the camper hooked and other gear in the bed I had about 1k extra weight on the rear axle. Annoying AF.

 

[JKSchnoo]

This whole thing is seriously stressing me out and giving me major buyers remorse. Part of me wants to just sell it to the closest ram dealership

 

[flan]

This whole thing is seriously stressing me out and giving me major buyers remorse. Part of me wants to just sell it to the closest ram dealership

It’s not just a Ram thing. Put the same trailer behind a similar wheelbase vehicle and you will likely get the same results. When I was getting my ass kicked towing on I-81 I passed a Chevy bouncing along just the same. We ended up at a rest stop at the same time and I remarked about the road and he had some choice words for it as well.

 

[Brutal_HO]

Concrete is great in a passenger car and until the OTR trucks have their way bangin it for a few months. That stretch of I-25 is and has always been, regardless of how many times replaced, a giant turd sandwich.

The way it's grooved is also rough with some high performance car tires - tramlining like a MF with a set of Pirelli P Zero on my A6. I couldn't get the replaced fast enough. Pilot Sport 4S are great for the summer.

 

[2001WS6]

This whole thing is seriously stressing me out and giving me major buyers remorse. Part of me wants to just sell it to the closest ram dealership

Unless you trade it in on a car you're going to have the same issue with any truck.

 

[2001WS6]

It’s not just a Ram thing. Put the same trailer behind a similar wheelbase vehicle and you will likely get the same results. When I was getting my ass kicked towing on I-81 I passed a Chevy bouncing along just the same. We ended up at a rest stop at the same time and I remarked about the road and he had some choice words for it as well.

It's so bad my Bro in-law was almost getting motion sickness.

 

[BikePilot]

If it's really bothering you put full Thuren suspension on along when airbags and cradles in the back for towing. It'll ride amazingly well, as well or better than most half tons, and still tow just fine.

 

[AH64ID]

Thanks for everyone’s reply. Today I started regretting getting the 3500, but am seeing that people still have the bouncing on concrete with the 2500 too, both gassers and diesels. Airing down the tires doesn’t seem to help much with the concrete seams, and looks like my mileage is going down, but it’s only been a day.

What did you drop the tire pressure to?

 

[JKSchnoo]

Unless you trade it in on a car you're going to have the same issue with any truck.

So you dont think the weight of a diesel engine would prevent the bounce on concrete highways better than the 6.4L Hemi I have? Or going down to a 2500, combined with diesel for a better ride? I guess from what everyone has said on here, even the heavier diesels bounce on concrete seams.

What did you drop the tire pressure to?

I now have around 45 in the rear, and 50 in the front.

It’s not just a Ram thing. Put the same trailer behind a similar wheelbase vehicle and you will likely get the same results. When I was getting my ass kicked towing on I-81 I passed a Chevy bouncing along just the same. We ended up at a rest stop at the same time and I remarked about the road and he had some choice words for it as well.

Yeah that makes sense, I started thinking I needed to trade in for a diesel, or a 2500 rather than my 3500 6.4 hemi, or look at another brand of truck. I loved my Ram 1500, and never felt anything like this on the same stretch of highways. Do you think the airlift bags help at all?

 

[AH64ID]

So you dont think the weight of a diesel engine would prevent the bounce on concrete highways better than the 6.4L Hemi I have? Or going down to a 2500, combined with diesel for a better ride? I guess from what everyone has said on here, even the heavier diesels bounce on concrete seams.

I now have around 45 in the rear, and 50 in the front.

Yeah that makes sense, I started thinking I needed to trade in for a diesel, or a 2500 rather than my 3500 6.4 hemi, or look at another brand of truck. I loved my Ram 1500, and never felt anything like this on the same stretch of highways. Do you think the airlift bags help at all?

It’s more related to wheelbase than anything else.

If the truck is empty you can go lower on tire pressure to see if it helps. 45F/35R is enough to support an empty hemi with a few hundreds pounds in the cab.

 

[Power247]

Yeah I’m starting to understand this. Did you notice any significant difference between the diesel and gas ride quality on concrete like that? From reading dozens of forum posts there are many diesel owners experiencing the same thing. Just hoping I didn’t concede ride quality getting the 6.4L hemi

It's exactly the same on my new truck (Hemi) as it was on my old one (Cummins).

 

[JKSchnoo]

It’s more related to wheelbase than anything else.

If the truck is empty you can go lower on tire pressure to see if it helps. 45F/35R is enough to support an empty hemi with a few hundreds pounds in the cab.

Is that going to kill my mpg?

 

[AH64ID]

Is that going to kill my mpg?

I’ve never noticed a difference in proper pressure vs overinflated tires. Underinflated is different, but those pressures aren’t underinflated for an empty hemi.

 

[flan]

So you dont think the weight of a diesel engine would prevent the bounce on concrete highways better than the 6.4L Hemi I have? Or going down to a 2500, combined with diesel for a better ride? I guess from what everyone has said on here, even the heavier diesels bounce on concrete seams.

I now have around 45 in the rear, and 50 in the front.

Yeah that makes sense, I started thinking I needed to trade in for a diesel, or a 2500 rather than my 3500 6.4 hemi, or look at another brand of truck. I loved my Ram 1500, and never felt anything like this on the same stretch of highways. Do you think the airlift bags help at all?

I don’t believe the bags helped or hurt. I remember my 1996 regular cab long bed 2nd Gen towing with leaf spring in the rear no bags riding like a bucking bronco going through there as well.

 

[phatboy64]

I must be a unicorn. I drive down 81 (I78 also at times) through Pennsylvanian on my way to NC all the time, been doing it for years. I don't remember which sections are concrete or not but I have never experienced "porppusing" and that has been with four different model year 3500 SRW SB. Load, unloaded, pulling a trailer...
I don't disagree that concrete roads have their issues.... If it is so bad that you are getting car sick there's gotta be something else going on....

 

[Wanderlust073]

It’s the road sections here. He can buy a hemi (I have) or a cummins (I had) and it’s the same either way. Carli suspension didn’t fix it. 500 pound topper on the bed and 400 pounds of **** in the bed doesn’t fix it.

I think if a bunch of people all say its the wheelbase on these trucks combined with how these certain sections of pavement are built, and there are literally years and years of the same complaints across multiple brands searchable online, then that’s probably just the way it is.

Good luck.

 

[Nick]

I had an 07 Mega Cab 3500 . It had a real bad hop over expansion joints . My son made a couple of rear traction bars ( nothing radical) they made a huge difference keeping the back wheels on the ground .

 

[yeska]

Hi Everyone-

I just traded up from my 1500 to a new 3500 6.4L SRW. On sections of highway or streets that are concrete, it starts this rhythmic, fast and continuous bouncing up and down. Feels like I’m going to bite my tongue off. The concrete itself looks smooth, but for some reason the truck gets into this bouncing rhythm immediately.

However, on asphalt highways and streets it rides great. A bit rough when hitting random bumps, but is what I expected with such a stiff suspension, and how it rode when test driving. After reading the forums I dropped the tire pressure down to 50 front, 45 rear, but it still didn’t seem to do much for the concrete driving.

What is going on here? Would adding steel bumpers front and rear help by adding weight? Billstein shocks up front? Air suspension?

Any help is appreciated

That's some ******** concrete work that your tight suspension is so delicately picking up. Hate that crap

 

[JKSchnoo]

I can’t stand it, so frustrating. When I look at other similar trucks on the highway it doesn’t look like they are bouncing at all. Wondering how it’s possible to haul a TT with your family in the cab and not have everyone puking and complaining. Literally worried I can’t put my new baby in a car seat in this truck.