Towing... air bags or helper springs?

manley · April 25, 2012

I'd like to improve the ride quality UNDER LOAD on my 2010 Silverardo. I have a non-NHT 6.2, and tow a Keystone Cougar 29 RLS travel trailer. It weighs in at 6,462 (UVW) and has a GVWR of 7,800. When the weight is distributed using my Hensley Arrow hitch, I only squat 1" in the rear, and the front is at unloaded height.

I don't really need additional carrying capacity, or "help" from the helper springs or air bags. However, I would like to improve the ride quality when towing. Specifically, I'd like to eliminate the "bounce" that you get from expansion joints on concrete highways and bridges, as well as from just general highway disrepair.

What does the forum knowledge recommend? Are Hellwig helper springs the "gold standard," or is one brand just as good as another? What about Firestone / Ride Right air bags? (I really don't want to spend a lot of money, but if I can easily / quickly / cheaply improve the ride, am willing to spend SOME money.

Thanks in advance.

scott

nht mike · April 26, 2012

First I would call Hensley to see if they have any sugestions. What is the weight rating of you hitch bars as compaired to your hitch weight? Used bars are pretty inexpensive and easy to swap around. You may just need to move more load in the trailer forward then tighten the hitch bars.

manley · April 28, 2012

Thanks, Mike.... I probably ought to do that as well!

Another question:

If I were to swap out the crappy OEM shocks, which is better, the Bilsteins or the Rancho.

Not needing/wanting to add lift, as it is already leveled with a 2" Fat Bob's kit... so I assume that I am talking about the Rancho RS5000 or the "blue & yellow" Bilsteins like I had on my '97, right?

music · April 28, 2012

A few questions:

Are you sure the spring rate is the issue?

Does it sit close to level when engaged?

Are you sitting into the overload springs when traveling?

What pressure are you running in your tires?

The "porpoising" you describe is a harmonic between the trailer balance & spring rate, truck springs, tires & pressure, and shocks.

manley · April 28, 2012

Music... wow! I'll try to answer:

Spring rate? Nope, don't know what the issue is, but know that it could be "better"

I've only got 1" of squat in the rear, and the front is at unloaded height.

Don't have overload springs, and probably wasn't clear enough up front... I am considering how to improve the ride.

Tires pretty much stay at 35 PSI all the time, they are Goodyear P265/70R/17 (yeah, I know that LTs would help with stability, but that also hurts unloaded ride quality and fuel mileage!)

Are what you are suggesting that the porpoising might be eliminated by changing speed (the balance?)

Thanks again!

music · April 28, 2012

Are what you are suggesting that the porpoising might be eliminated by changing speed (the balance?)

I'm suggesting that any one of these can help/hurt. First, I'd bump the tire pressure when towing to at least 40 (or the max allowed of 44). You should have a stock overload spring... it's the bottom (heavy) spring on the stock spring set. If you're sitting down ~1", then you should be into them. You *want* to be on the overloads, since they're very stiff, and dampen the spring rate a *lot*. Adjusting tension on the hitch system is the next thing to try (other than tires), and even adjusting the trailer load to put more or less on the tongue. I'd rather be over GVWR on the truck a little, rather than too light of tongue. I'm a little over myself, but a few hundred lbs under the axle rating... which is fine with me.

Don't get me wrong, a helper spring may "help", but not if it keeps you from sitting into the overloads (which is very possible). I see helper springs, add-a-leafs, and airbags as devices for direct loading/hauling. A WD hitch system shouldn't need them, if the bars are the right size. Do your spring bars match the tongue weight?

Edit: and yes... driving a different speed over the joints *will* change the response. When looking at this exact same issue a couple of years back, I looked at the Bilstein HD shocks, but didn't do it.

manley · April 28, 2012

The spring bars are 1,000#'ers, and they are cranked all the way...

The specifications of the trailer say that tongue weight is 620 pounds.

+ 100 pounds +/- for the LP & tanks

+ 50 pounds +/- for the battery

+ 190 pounds for the Hensley Arrow

+ (probably) 250 or 300 pounds of crap in the front pass-through storage

Yeah, it's likely that I'm a little heavy.

By the way, the trailer GVWR is 7800 pounds, and the truck is rated for 9,400 tow capacity. It might be interesting to take a trip to the scales...

music · April 28, 2012

I'm pretty sure I'll go w/ a good LT tire when I change. It will hurt unloaded mpg and ride, but I feel it's worth it for the safety upgrade when hauling a family down the road w/ the camper. I'm pretty sure that one change will also do more to eliminate squirm, and firm up the "bounce" over expansion joints. Bilstein HD shocks may help too, and may even be needed to handle heavier tires when unloaded, but I'll wait and see. If I push around on the truck/camper when hooked up, most of the "motion" is in the tires.

manley · May 1, 2012

Ranch RS5000's installed this morning... we'll see if that helps some!

Thanks again for the recommendations, music & NHT Mike!

scott

dave_benn · May 3, 2012

I have the Firestone ride-rite air bags, i also have a Jayco travel trailer with weights similar to yours. I left the air pressure at the min. 5 lbs when i towed it last time, and it sat like your describing, 1" squat in the back end. I think it rides better with a little more air in the bags but thats also cause it isn't nose high going down the road. I also have bigger tires, 295/70R17 Load D i attribute this to being the biggest help when towing.