Need Suspension Mods

[cheftim]

I've got the rig in my sig: 2017 F350 with and Arctic Fox 990. It's me the wife and the dog. Don't haul much liquid. Figure I'm around the 4000 lb mark.

I've put in the Rancho adjustables front and back, Firestone Air bags, and the larger bump stops that engage the overload spring earlier.

Not loving the air bags on this rig. I've tried anywhere from 10 to 60 lbs.

At 10-20 lbs, I hear something banging when I hit a bridge expansion or frost heave in the road, like something's bottoming out.

Above 20-25, I lose the banging but it's way too bouncy side to side.

I'm thinking maybe a Big Wig might help out on the side to side but I feel the issue is probably the air bags and something like helper springs are the most appropriate solution.

Hoping to get some feedback from folks that have the same truck and similar weight camper to get a more solid ride that isn't compromised when camper is off.

[Grit_dog]

Tri-beard. If you have 5500lbs ish in a short bed camper, you should not let the wife pack it.
Are you carrying rock collections like some of the folks here?

[Grit_dog]

BigfootBill wrote:

billtex wrote:

towpro wrote:
it sounds like you must have over load springs, that work as the truck body drops the springs come into contact with the overload spring perches on the frame.

Your not loaded enough to make them come into play full time so they BANG every time the springs hit them
As you crank up the air bags they you are raising the back so they never hit again.

This.

Ditch the airbags and add lower Stableloads . You’ll be all set.

I'm not convinced that this is true with a 4000 pound camper. The lower pressures he was experimenting with should have allowed the weight to compress the suspension enough to get full engagement out of the various parts of his OEM suspension.

I was having issues and called airlift who makes my bags and tech support recommended running up to 95 psi. I find I like the ride around 75 psi so consider trying out higher pressures. Air it up and see how high you can go before those extensions you talk about lose contact and you may find that you can go higher pressure and still be comfortable with the suspension.

In addition to raising the vehicle as the pressure increases, the "firmness" also increases. It's a dance between the vehicle springs and the airbags and the goal is to find the sweet spot where they work together the way you want.

This is a very interesting statement and I’d like to try it. Guess I figured the more air the bouncier.
But what I don’t understand is how do you drove around with the rear end up in the air?
Unless you’re really heavy on a lighter duty truck.
I’ve got 4500lbs ish on an old 2500 and 60 psi levels it , full. 70 is about stock ride height. 90-100psi would look like it put a lift kit in the back.
Like to know more about your setup bill.

[Bedlam]

You may be able to SumoSprings or Timbrens in parallel with your bags if you do not want to change out the spring pack.

[TriBeard]

You really should try and get to another scale. Those weights seem off to me, either that or mine are just crazy. I’ve weighed my truck and camper twice (af811 and 2018 ram 3500 srw) and I’m at 9k loaded on the rear axle. I’m heavier than everyone else online seems to be and I’m not sure why, but you may be as well. I just upgraded to 19.5 wheels and tires to handle the load and they’re a huge improvement for stability even when just in the camper when the truck is parked.

Check your compression on your airbags when the camper is loaded. Mine was less than 3 inches between the top and bottom metal disks for the bags and so I’m having to move up to the 7500xl series to handle the load. I have stableloads also which help but didn’t solve any of my issues on their own. I can only have the lowers cause rams don’t have upper overloads so if you have those too maybe they’re helping, not sure.

AFs are heavy and I honestly don’t know how someone can carry one safely and be under fire ratings and whatnot without a dually or 19.5s. Not saying that it’s impossible or that people don’t have combinations that work, but it hasn’t been my experience and I have what is supposed to be one of if not their lightest units.

[Bert_the_Welder]

noteven wrote:

cheftim wrote:
Buzzcut1,

Yeah, tires are rated at 3415 each so that will need to be upgraded. Thanks for that feedback.

Anyone have E or F tire suggestions that are decent on the highway and are around 4k load range?

I'm leaning towards Supersprings as well.

Take a look at Nitto Dura Grappler tires.

Those look promising. Had Terra Grap's on my current truck. They were just OK. found they wore faster then others and rain grip wasn't as good. Those ones look like they'd be a nice middle ground tread for forest roads and pavement.

[billtex]

cheftim wrote:
Thanks for all of the feedback from you all.

I'll be ready for new tires in the spring so I'll be upgrading both the wheels and tires to be better suited to the weight I'm carrying. Decision now is stay with 18" or go with 19.5". Haven't found a compelling reason for either one yet.

I'll also be adding a Superspring. Looks like I'll have to get rid of the air bags altogether as it looks like they can't coexist.

Heading up to one of my kid's house next week and will use the camper for social distancing. There's a Cat scale nearby and will jump on with all tanks empty for another reading.

I ran SS’s and bags on my last 3/4 ton truck.

Not sure The advantage of adding SS’s to a 1 ton. Why not take full advantage of the OE spring pack?

[noteven]

cheftim wrote:
Buzzcut1,

Yeah, tires are rated at 3415 each so that will need to be upgraded. Thanks for that feedback.

Anyone have E or F tire suggestions that are decent on the highway and are around 4k load range?

I'm leaning towards Supersprings as well.

Take a look at Nitto Dura Grappler tires.

You need tires that are load index 128 ish to get 4000lbs

I had good service from a set of Firestone H somethings, 18's rated at 3920(?)lbs I think. They were Oh My God new takeoff stock OEM tires from a new Ram truck. $600 for 4 and ran them doing lots of towing and hauling for 2 years...then they went on a pilot truck for another 25,000 - but they don't carry much weight.

[cheftim]

Thanks for all of the feedback from you all.

I'll be ready for new tires in the spring so I'll be upgrading both the wheels and tires to be better suited to the weight I'm carrying. Decision now is stay with 18" or go with 19.5". Haven't found a compelling reason for either one yet.

I'll also be adding a Superspring. Looks like I'll have to get rid of the air bags altogether as it looks like they can't coexist.

Heading up to one of my kid's house next week and will use the camper for social distancing. There's a Cat scale nearby and will jump on with all tanks empty for another reading.

[Bedlam]

My 2005 F250 was at 7000 lbs on the rear axle with a 2012 Arctic Fox 811. Adding my tongue weight of an 8000 lb trailer made it 8000 lbs on the rear of the truck. To ride level and safe at that weight, I added the following:

Vision Heavy Hauler 81 rims rated 4500 lbs each
245/70R19.5 LRH PR16 tires rated over 5000 lbs each
Ford OEM rear stabilizer bar
Upper Torklift StableLoad pads
Lower Torklift StableLoad wedges
Firestone Ride Rite airbags rated at 5000 lbs and plumbed individually
Rancho RS9000XL adjustable shocks

This combination crossed the Rockies on three round trips and was solid for 30,000 miles before I upgraded to my current truck and camper. It handled the Midwest winds well and had no problems with windy mountain roads.

If had to this again, I would not hesitate but would probably replace the entire rear spring pack rather than build it up with with bags and StableLoads.

[JIMNLIN]

Buzzcut1,
Hit the local dump scale today. Mind you, they use the scale to charge contractors for dumping.

Front: 4440
Rear: 7540
Total: 12000

Curb weight of the exact truck on nada guides says curb weight is 6600. Not sure how accurate that is but even if it was 7k, that'd mean the camper was nearly 5k.

We know your F350 SRW weighs much more than 6600 lbs. However thats not the important number for carrying a heavy TC unless your state requires some kind of weight for registration purposes.

The '17 F350 has a 7320 RAWR. RAWR = the lessor of a tire/wheel and rear spring pack. 18"-20" tires can be upgraded for more load capacity however OEM Ford wheel have a 3590 lb load rating according to Fleet Ford specs so your truck will need higher rated wheels.

And of course the rear spring pack will need help also. Lots of different options out here in that area....some good some not so good for carrying a top heavy TC.

That 4331 payload sticker is a gvwr based sticker (front and rear axle) and cannot all go in the bed of the truck over the rear axle. CAT scale axle weights show many one ton SRW trucks empty rear axles can weigh in the 3300-3400 lbs range. Simple math say 3400 lbs less the trucks 7230 rawr = around 3800 lbs max weight.

I 'spect that 7540 rear axle weight is darn close....yer overloaded on tires and wheels.
I see higher rated tire/wheel combo and a better overload system for the back of that SRW truck.

[cheftim]

Buzzcut1,

Yeah, tires are rated at 3415 each so that will need to be upgraded. Thanks for that feedback.

Anyone have E or F tire suggestions that are decent on the highway and are around 4k load range?

I'm leaning towards Supersprings as well.

[Oregun]

I agree with Buzzcut check your tire rating. My F350 fully loaded is similar with 4000lbs on the front axle and 7600lbs on the rear axle carrying Adventurer 910FBS camper with 19.5 Tires.

[Grit_dog]

That weight looks about right. Nothing magical. Actually encouraging as it’s not maxing anything out.

[Grit_dog]

I’ll trade you my 860 for your 992. That should help with weight and center of load!
Seriously though, your truck is big enough, unless you expect it to drive like it does empty.
You have a 2 ton white whale on the back. And sounds like either your expectations aren’t in line with how it’s going to handle or you don’t understand why it’s acting the way it does.
It’s fine. Go camping. Yes overload springs will slap if their not engaged. EngAge them.
And if you can reasonably drove it around with very little help from air bags then you again don’t know how it should ride or it’s hauling the weight about as well as it should.

[towpro]

Yes, I recall our 2016 990 was no where near what your saying. Truckcamper mag shows wet weight 4,781 pounds. my Ram 3500 2wd dually was just a couple lbs under 14,000 GVW with camper on headed to beach for a week, including a couple hundred lbs of tung weight, empty waist tanks and maybe 10-20 gallons of water between cold and hot.