Porpoising, sway, coil vs lead, airbags, TT vs 5er, and more!

[UglyViking]

Hey all,

I recently took a trip from NH to MT and back over 3 weeks in July. The towing experience was fine, although less than ideal. I wanted to share my current setup and ask for some feedback from this group before I continue spending money on mods in an effort to rectify the issues/challenges I experienced.

Truck setup
2019 Ram 2500 Cummins 4x4 - CCSB
Full Thuren suspension with +1" rear soft ride coils and King shocks
37x12.5x17 Falken Wildpeak AT3Ws

Trailer & tow setup
32' Salem TT, single slide dual axle
Husky centerline
Timbrens

Ok, so I followed the husky directions to make sure that it was setup properly to be as level as possible, but I think I still may have it a little light on the hitch side, which I'm sure isn't helping things. I noticed a handful of issues during our trip. Trailer swap was basically constant, with a more pronounced sway going over bumps. I think that may have some amount to do with the fact that while my tires are rated for the weight, the sidewall isn't super stiff and there is a lot of it (37s on 17s). I think the larger issue though is the 5 link in the rear causing a lot of back and forth movement over bumps. I thought the Timbrens would help with that, but I expect that they are really only helping the stability with higher COV loads and with preventing too much sag, especially due to my soft rear springs.

Airbags are an option that may help, but I'm not willing to reduce my off road capabilities by directly connecting them, so that means daystar cradles, which I think will perform better than the Timbrens, but I'm not sure by how much.

The Husky hitch I'm using is correctly setup on the hitch, but the connection on the trailer isn't setup properly due to where the battery brackets are. I've not yet modified the brackets because I plan to change up the trailer in the near term.

The bigger issue I've got, over the sway, is the porpoising I experienced. Even on I-80 and I-90 it was absolutely horrible. Again, I think part of that may have been that the hitch was setup less than ideal, but I believe part of it may just be the 2500 coil and 5 link in the rear, and I'm not sure how much it's worth fighting for it.

We also realized that the current 32' trailer we have isn't ideal for how we would like to "camp". So we are looking at either a big travel trailer (38' or 40') 3 slide bunkhouse option like an Outback 340BH, or moving up to a 5th wheel like a Montana 3857BR. My fear is that the length of the TT is going to exacerbate the sway and porpoising like nothing

Lastly, we are expecting our second child, and I've recently become aware just how big car seats are. So I'm starting to wonder if a megacab would be a better fit for a family trailer vehicle (although it comes with a lot of downsides for an offroad trail vehicle). This isn't a main deal, but I'll be curious of anyone going from a crew to mega and how it was daily driving. This thing is already a beast to park in some places, a mega is gonna be even worse.

Potential truck options
So, I've come to a bit of a crossroads, and I'd love any first hand experience from anyone.

1) Add airbags and cradles, potentially also adding stiffer Carli R2 rear coils to help support the load and reduce sway.

2) Change to a 3500 SRW. This gives additional legal payload, but more importantly, changes to leafs which should be better at negating sway and hopefully reducing porpoising.

Open questions on trailer
Do 5ers have less sway than tow behinds? I think the overall length of the 5er is a big selling point, because even a 40' 5er is going to be notable shorter than a 38' tow behind.

Do 5ers have less porpoising than travel trailers?

The other option would be that we could go all the way to a dually, and basically treat it like a dedicated tow rig. That's nice because of the added stability and all that, but it would be the most expensive option by far.

My ideal would be keeping the tow behind, primarily because I could continue using my truck as a daily, as well as keeping the cap and putting in a bed slide system for added non-rv camping awesomeness. That said, I get that a dedicated tow rig will perform better than something that I'm trying to make the jack of all. A dually with a jeep would give me the best of all worlds, at the literal financial cost of all things.

Any feedback on similar setups, especially those who treat their rigs as both off road rigs and tow rigs would be awesome. I'd prefer to keep my 2500, as I've already spent a bunch of cash on it and I really love it. I'm happy to spend the cash on airbags, coils, new WDH, etc. to make it work, but I'm worried that I'll spend all that cash and then still have a system that is giving me crazy sway and porpoising which makes long trips very annoying.

Thanks for attending my ted talk.

 

[H3LZSN1P3R]

I have none of those issues but i have a LB which the longer WB makes the ride better. I know some people have had those issues with timbrens which is where the bags prove better…. But biggest issue is light tongue weight thats going to cause all kinds of problems towing

 

[davidh1329]

That is a lot Out of all that, what caught my eye was, "....a little light on the hitch." Trailers hate that and too little weight on the hitch will induce sway. There is a video out there (youtube?) that shows a model car on a moving belt pulling a trailer with moveable weights. The difference in behavior (sway) is extreme when they move weight to the back of the trailer. All those other variables can likely improve sway, but putting more weight on the hitch will make a huge difference. From personal experience - a 5th wheel tows better than a TT, a 5th wheel does not sway, moving weight in the trailer makes a huge difference, a 3500 tows better than a 2500. The worst sway I ever had was pulling an empty 28' car hauler.

 

[tchur1]

I can speak to some of your thoughts/questions/concerns because we are going through a similar calculus right now so ill share my ideas and what I have come up with based on research up to this point.

My 3500 SRW is rock solid/stable towing our boat. I know its not a 32' TT but our boat when hooked up is about 28' from hitch to the end of the swim deck and just shy of 10k pounds. I experience zero sway/porpoising/swap when towing at any speed. Im also running 37s on 18s. I think as a baseline no matter how much you do to the 2500, its not going to tow like a 3500 w/ leafs. I used to have a 2500 w/ firestone bags that we loaded an artic fox on it and towed a different boat with, it couldnt hold a candle to the 3500. So I guess the first question for you to answer is how much you want to keep your 2500 and be OK with the compromises that come with towing with that truck.

We are also considering buying a 5th wheel and traveling/working from the road next year and thus have started looking at pretty big premium 5th wheels (39-42 feet). From everything I have read, 5th wheels tow significantly better then bumper pulls because you are placing that weight over the rear axle vs the rear bumper. My truck has 4k payload rating which is right on the edge capacity wise for the 5th wheels we are looking at, so if we do this ill probably upgrade to a dually because trade in values on my truck are still crazy high and I can come out in a wash.

I cant answer your questions but I think the equation you are solving here is how much you care about off road capability vs towing performance vs living with the compromises of your current truck. Based on what youre looking for, I dont think youre going to be able to check every box, your best bet is probably a 3500 SRW but thats not a cheap option.

Idk if this brain dump helps but figured I would type it out.

 

[rudyyoko]

Trailer hitch weight will determine your ability to tow properly. I pulled a 30 foot bumper pull and with the weight balanced properly I did not have porpoising or sway problems even when I was towing the same trailer with my 1500 ram crew cab with the 6.4 bed. I pulled the same trailer with my 2022 cummins ram 2500 4x4, crew cab, 6.4 bed with no issues. The difference between my 2500 and yours is I have have stock height, stock 18 inch tires and wheels. Good luck.

 

[jsalbre]

The trouble is, as you've laid out, you have a heavy, low payload truck which you've softened the suspension on, and then attached a very long very heavy trailer. Timbrens can help, but even though they're soft they're still just a bumpstop, so you're already sagging a good bit before they come into play. If your WDH is set up properly you're probably not even touching the timbrens.

The sway could be because your WDH isn't tight enough and/or because your trailer loading has the tongue weight too low. You'll need to scale it to be sure.

Putting an even larger trailer on there is going to make it worse, and a 5th wheel is going to kill that poor thing. If you don't want to change trucks your best options are airbags, which may or may not be enough to help, or going back to stiffer rear springs, and maybe still airbags. I'm sure you enjoy the softer ride with the Thuren springs, but if you change to a 3500 you're going to lose that anyway. If your plan is truly a big 5er then I'd go 3500 for sure. The inboard springs on the 2500s, plus the fact you don't have much payload available makes it a no brainer there.

 

[H3LZSN1P3R]

Throw a set of bags on there and run the trailer a bit tongue heavy

 

[gimmie11s]

Can someone explain porpoising? Maybe we call it something different out here, but I don't know what that is.

 

[UglyViking]

If your WDH is set up properly you're probably not even touching the timbrens.

The sway could be because your WDH isn't tight enough and/or because your trailer loading has the tongue weight too low. You'll need to scale it to be sure.

My WDH is setup properly, at least according to the instructions from Husky, but it's probably not 100% due to the issue with the WDH connection to the trailer. The issue is that I can't fix that unless I cut and weld a battery holder in a different spot. I suppose there isn't a ton of harm in doing that, but I was a bit nervous about resale.

I was riding on the Timbrens though, confirmed on that.

Can someone explain porpoising? Maybe we call it something different out here, but I don't know what that is.

It's basically a up and down motion that seems to be most visible in your hood area. Your front and rear go over a bump, and the trailer follows, but basically takes a while to settle down so it transfers front to back and sort of feels like you're on a small boat on the ocean. I am not sure if there is another term, always heard it referred to as porpoising.

I think my main concern overall right now is that I love how my 2500 handles on and off road, but I'm less enthused about the towing. I can stick bags under it, then swap coils to the R2, but at that point I'm over 2k more into it, and may end up switching it out anyway. I guess it's not a huge loss, but it's there.

I'm also curious on the 5er vs travel trailer. I'd prefer the 5er while using it, but basically the tt outside of that because I can setup the bed for camping. I am prob trying to do too much with a single truck, which is probably my answer.

The one thing I know is that I can make a 3500 less stiff by going with softer springs. That won't change how it tows, but it will change the squat. I can add airbags to get up to max payload without sacrificing much travel either, which is nice.

 

[MEGA HO]

To answer your mega cab question, before ordering my mega I spent quite a bit of time in CC and in MC trying to decide between a CCLB or a MCSB. Mega cab won. If there was a MCLB I'd probably get it instead. MCSB is slightly longer than CCSB but slightly shorter than CCLB so it ain't too bad and we really enjoying all the extra leg room and behind the seat storage.
I have a 4 yo boy who sits in a car sit and there's plenty of room for him to stretch his legs without moving the front seat all the way forward.
My wife is 5' tall and she has no issues driving this thing, we live out in a country but go to city every day.
My RAM 3500 is our DD for the warmer months of the year, we have a smaller SUV with studded set of winter tires for the winter while RAM hibernates in a garage.

 

[MEGA HO]

Can someone explain porpoising? Maybe we call it something different out here, but I don't know what that is.

Yup it's front to back rocking rather than side to side. Imagine 4 fat 400 lbs guys standing on your rear bumper and jumping up and down in unison.

 

[Sam 15]

Can someone explain porpoising? Maybe we call it something different out here, but I don't know what that is.

Porpoising is front to rear bounce; the front hits a bump, then the rear hits the bump, and they both bounce independently of each other, creating an oscillating motion. I believe it's due to incorrect trailer setup...google is your friend.

 

[Jacob]

Your truck can be an offroad vehicle and a tow rig but I wouldn't expect it to do both perfectly.

 

[flan]

I just installed airlift 5K bags and Daystar cradles about 2 weeks ago. I have a 27’ TT and just did my first trip with them from CT to NH, about 230 miles each way.

I have a equalizer WDH and it does a very good job of eliminating sway. Also a decent job of transferring weight back up to the front axle. When I had the suspension setup from the factory I was pleased with how the truck sat and towed with just the hitch.

I went ahead and put in a 2” thuren leveling kit which left the front only 3/4” lower than the rear. When I dropped the trailer on the back it sat a bit lower than the front and I don’t like that look. Also if towing at night the headlights are in oncoming traffics eyes. I “tightened” the hitch up a bit and got it a bit more level but just couldn’t get it to where I wanted it to be, about 1”+ in the back higher so I got the bags.

I’ve towed my camper with just the wdh thousands of miles, and now after this trip with the bags I’m happy I went with them. It eliminated the minor porpoising on bridge expansion joints that I had, and even after dropping the trailer at the campground I left the bags inflated (30psi) and didn’t mind the ride quality on the state highways we rode on during the week. The rear end seemed a lot more planted. We did do some dirt forest roads and the ride was a bit rough so I pulled over and let the air out of the bags. Strangely enough the ride was almost better with air in the bags. With air in the bags my hitch didn’t rattle on bumps, with the air out of the bags it did. Can’t tell ya why, I’d think the opposite. I may try letting half the air out in the future.

I know it’s not an identical setup to yours, but similar so I thought I’d share my experience with you.

 

[gimmie11s]

Porpoising is front to rear bounce; the front hits a bump, then the rear hits the bump, and they both bounce independently of each other, creating an oscillating motion. I believe it's due to incorrect trailer setup...google is your friend.

Google is my friend eh? thanks cool guy!

 

[jetrinka]

OP was your Husky hitch installed by the dealer? If so I’d be going over their install with a fine-tooth comb.

I had an identical hitch installed when we bought our TT and I started going over their install and found numerous things wrong. I can go into details about it if you’d like but after I got done reinstalling it and torquing everything to the manuals spec discovered the hitch to be quite defective and causing all sorts of problems - the largest being the trunnions wouldn’t pivot which would literally steer the back end of the truck after taking a turn resulting in lots of countersteer being needed to keep the truck going straight down the road.

Lemme know if you want more details but you won’t find any love from me regarding my trailer dealer or the garbage Husky hitch they installed.

I now tow the trailer on a B&W drop hitch and some airbags and it’s a world of difference.

 

[Bcrouse]

Im currently towing our 34’ TT with our 2021 Ford Expedition with max tow. Its right on the edge of hitch weight. We cant fill the fresh water tank as itd add too much hitch weight. Its got coils all around like the 2500s and I have not been a huge fan. Its very sensitive to weight placement in the TT as well as making sure the hitch is set correctly. I have a Weigh-Safe WDH and its been pretty easy to dial in. I can get the Expo pretty flat. All that said, its a very active driving experience. Exhausted after driving 8hrs.

Ordered a 2022 3500 Megacab SRW for longer trips and easier stops at truck stops for fuel etc. would also give us the ability to travel with some freshwater in the tank. A better driving experience too. I told myself I wasnt going to order a dually. Been there done that.

Then we started looking at larger trailers, 5th wheels etc and canceled the SRW and ordered a DRW. Its a vicious cycle.

 

[Brutal_HO]

More WD and add bags. Reevaluate.

The tires aren't helping, but tend to manifest their behavior more in (truck) sway/roll than what you have going on.

Though leaf sprung, I added bags to my 04.5 2500 to reduce porpoising with my 5th wheel which was exacerbated by double towing a 4K boat. It absolutely changed the towing experience. I never once contemplated Timbrens or SumoSprings as I consider them softer versions of a bumpstop.

RE: WD "adding weight to the front (steer) axle." Keep in mind that it also transfers some of the weight to the trailer axles. That "tighter" WD connection between truck and trailer will help reduce not only the RAW, but also help reduce the porpoising.

Towing with a 3500 vs 2500 is a whole different experience, so much more stable and relaxing.

 

[henrys]

Have you considered downsizing your RV to a truck camper? They get really roomy inside with slides and it leaves the back of your truck open for towing anything you want. They are heavy though so you definitely want a 3500. Take a look at arctic fox campers.

 

[MEGA HO]

Have you considered downsizing your RV to a truck camper? They get really roomy inside with slides and it leaves the back of your truck open for towing anything you want. They are heavy though so you definitely want a 3500. Take a look at arctic fox campers.

That's the route I went but I didn't want a huge one with slide outs. For some Arctic Fox, Host, Lance larger models with slide outs even a 1 ton DRW is getting too small.
It sounds like OP is considering to upsize though and ANY slide in camper will be a downsize irrespective to how easy it is to drive with one + being able to tow something else.
I know of some folks however that went from a 5er to a larger slide in camper and they're perfectly happy. I love boondocking so I'd never ever get anything large, definitely no 5er as they'd be terrible off the pavement.