F350 Suspension with Flatbed and Fulltime Camper

[montypower]

You have no rear sway... is there one in the front?

I don't have any sway bars.

 

[montypower]

How is locating the lower rear shock mounts up a couple inches working out? Seems like a great idea on the Superduty.

Massive improvement!!! Haven't hit the shocks or towers... LOVE IT. Should be the 1st modification when taking one of these truck off road.

 

[montypower]

I've located a very experienced, brand agnostic suspension guy, relatively close to home. YEA! He's a dealer for all the big names, including Carli and Deaver. So, If you were building a Super Duty ala carte, knowing it would carry 2000ish pounds 99.9% of the time, how would you do it? I like the idea of adjustable shocks, because we take time to adjust the air pressure anyway. I don't know who offers adjustability. I'm a noob/newbie to all this so I appreciate the guidance!

Check out my build thread for ideas... I'd build our truck exactly the same. We have 1.5years off road adventures with it so far. Really works well.

Fox DCS 2.5 Resi Shocks - From Accutune (they will tune for your suspension / load / use)
Deaver Leaf Springs (order directly from Jeff for what your load / lift)
Carli Offers many good parts (front springs, brake lines, shock resi mounts, track bar, etc)

Here's the deal... there is no "off the shelf" kit or product (one size fits all solution). It needs to be customized to perform well. Otherwise... it's like installing Honda Civic Shocks on a dump truck and expecting it to work well.

 

[eyemgh]

I don't have any sway bars.

Admittedly, I don’t know much about suspension. I do understand that higher speed roll mitigation and slow speed articulation are at odds with one and other. How does your setup work for high speed swerves, say avoiding an animal, with no sway bars.

 

[montypower]

Admittedly, I don’t know much about suspension. I do understand that higher speed roll mitigation and slow speed articulation are at odds with one and other. How does your setup work for high speed swerves, say avoiding an animal, with no sway bars.

I would NOT remove the sway bar with stock suspension!! However, if you have proper suspension built for the weight of your truck with performance 2.5" shocks properly tuned... then you would be surprised at how composed it will ride and handle (on/off road). Please note you need to drive for the weight/size of your vehicle. There's no way a 10k lb (11ft tall) truck will handle like a sports car... but with that limitation in mind this has been my experience:

The truck is well composed on road. Cornering lean on road is progressive and predictable - no problem exceeding speed limits on corners. We had a situation driving @ 65mph on the hwy with the camper (fully loaded) and pulling our 14ft (2 axle) enclosed trailer (4,000+ lbs). There was debris blown into our lane (high winds) at night (limited visibility) and required swerving onto the shoulder. Missed the debris which was great. Afterwards, I reflected on how composed the truck was. Rather surprised due to how quickly I had to react.

Here's the problem with HD sway bars.... you will "feel" the truck corner with less "lean" in ideal conditions. However, in emergency type situations you'll be more likely to lift a tire which could be extremely difficult to recover from. And any "uneven" terrain on/off road will induce sway. I prefer a more progressive and predictable handling experience. Hope that helps!

 

[eyemgh]

I would NOT remove the sway bar with stock suspension!! However, if you have proper suspension built for the weight of your truck with performance 2.5" shocks properly tuned... then you would be surprised at how composed it will ride and handle (on/off road). Please note you need to drive for the weight/size of your vehicle. There's no way a 10k lb (11ft tall) truck will handle like a sports car... but with that limitation in mind this has been my experience:

The truck is well composed on road. Cornering lean on road is progressive and predictable - no problem exceeding speed limits on corners. We had a situation driving @ 65mph on the hwy with the camper (fully loaded) and pulling our 14ft (2 axle) enclosed trailer (4,000+ lbs). There was debris blown into our lane (high winds) at night (limited visibility) and required swerving onto the shoulder. Missed the debris which was great. Afterwards, I reflected on how composed the truck was. Rather surprised due to how quickly I had to react.

Here's the problem with HD sway bars.... you will "feel" the truck corner with less "lean" in ideal conditions. However, in emergency type situations you'll be more likely to lift a tire which could be extremely difficult to recover from. And any "uneven" terrain on/off road will induce sway. I prefer a more progressive and predictable handling experience. Hope that helps!

Very much so. Thanks!

 

[rruff]

How does your setup work for high speed swerves, say avoiding an animal, with no sway bars.

You probably know this... but first thing to do is slam on the brakes! Then take your foot off the brakes when you turn the wheel. With a camper on, all these rigs will be poor at cornering. If you get the Accutune Fox setup like montypower, they will custom valve them to your specs and you also have adjusters. Shock compression damping makes a big difference in composure during sudden maneuvers. Stock shocks usually have very little.

 

[Ninelitetrip]

Same question but a slightly different platform from the original basis. Baseline is a 2014+ F350 Supercab SRW Chassis cab. 60 inches from cab to axle and another 47 inches to the end of the rear frame. Rear frame width is 34 inches vs the 37.5 inches of the pickup frame. No FX4 or camper package. Has a flatbed with a flatbed camper on it, Hallmark, FWC, Bison, OEV, etc. so well within the approximate 4700 payload capacity if the truck is stickered at the full 11,500 GVWR for the F350 SRW. Max tire would be 37's.

Do anything different or the same as previous replies?

 

[rruff]

Same question but a slightly different platform from the original basis. Baseline is a 2014+ F350 Supercab SRW Chassis cab. 60 inches from cab to axle and another 47 inches to the end of the rear frame. Rear frame width is 34 inches vs the 37.5 inches of the pickup frame. No FX4 or camper package. Has a flatbed with a flatbed camper on it, Hallmark, FWC, Bison, OEV, etc. so well within the approximate 4700 payload capacity if the truck is stickered at the full 11,500 GVWR for the F350 SRW. Max tire would be 37's.

I think the biggest thing to address is that you have a very torsionally flexible frame vs the fully boxed ones in the newer pickup models. You'd want pivots or a spring loaded interface between the flatbed and frame.

I think 2017 was the first year that F350 pickups had a boxed frame. If you get one of those you can hard-mount it which is much simpler and probably better over all.

 

[eyemgh]

On suspension I can't help much. I've only ever done stiffer springs and a modest shock upgrade (well, mostly). On the F350 we used to run the current Tremor size tire. Its larger size and higher than stock load index meant I could air down a bit for comfort, which really helps off highway for a rig heavily loaded and with a necessarily high spring rate.

For the 2,000-2,400# weight I think you've quoted, I don't think the SD will have any problem. Though I do understand you are looking for a more ultimate type set up.

Anyway it's not just the camper, it's all the"stuff" we bring along (incl the mods). With a replacement deck and loaded storage boxes, I wouldn't be surprised if you are indeed heavier, maybe a lot heavier.

For both these reasons (oem capability and possibly unknown final weight) myself, I'd try it all out first before making any desicions.

Except the tire, that I'd do straight from the dealer. 35s should fit clear with an oem or similar rim.

I’ve learned about that animal collision technique from a MC riding friend. I’m not sure though I could do it, not for lack of thought, but for habituated reactive responses. I need to practice!

As for the wheels and tires, 17” Method 701s with Toyo Open Country A/T IIIs in 35 12.5r17E will be swapped at the get go. ??

 

[Ninelitetrip]

I think the biggest thing to address is that you have a very torsionally flexible frame vs the fully boxed ones in the newer pickup models. You'd want pivots or a spring loaded interface between the flatbed and frame.

I think 2017 was the first year that F350 pickups had a boxed frame. If you get one of those you can hard-mount it which is much simpler and probably better over all.

Good points. I ask because one possibility is that with fleet sales and service trucks used chassis cabs are always a possibility for the budget minded. Although the last time I was really looking at these they were coming out of the oil fields and we’re just beat to a pulp. Most were being sold on to landscaping businesses.

 

[eyemgh]

Good points. I ask because one possibility is that with fleet sales and service trucks used chassis cabs are always a possibility for the budget minded. Although the last time I was really looking at these they were coming out of the oil fields and we’re just beat to a pulp. Most were being sold on to landscaping businesses.

I know this isn't on the budget lines, but I considered ordering a new cab and chassis before I ordered a complete truck. There were options I wanted that I couldn't get that way, but more importantly, the money I would have saved, would have been eaten to make it road legal to drive to CO for the bed.

I think if I was going to buy from a used fleet, I'd look for a government rig. They have mileage limitations and their service is usually good.

 

[eyemgh]

Nice !
We've used the 285 and 295 size on oem 18s so got the 4080# @ 80 tire rating. But are likely a lot heavier than you will be - just watch your rear axle weignt.

Had two sets of the A/T IIs, liked them but found they chunked out with our weight and all the gravel we used to drive. The A/TIII should be an all round improvement. We've stuck with Toyo and are running their C/Ts now and like them for our use.

btw I had never paid attention to liquid spring until you posted about it. Pretty nteresting. I see Buckstop is developing with them / offering it now for their F550 conversions.

I'll be watching you progress. Good luck with it !

edit for clarity

Even though the C/T might have been the better choice, we ski a lot. Having the snow rating keeps us from having to unnecessarily chain. We ran Wildpeaks in the past. Like that tire too, but the supply chain is empty right now.

Liquid Spring...well if a F350 conversion is anywhere close to what Buckstop is asking, we'll be doing a Carli/Deaver combo.

 

[Ninelitetrip]

I know this isn't on the budget lines, but I considered ordering a new cab and chassis before I ordered a complete truck. There were options I wanted that I couldn't get that way, but more importantly, the money I would have saved, would have been eaten to make it road legal to drive to CO for the bed.

I think if I was going to buy from a used fleet, I'd look for a government rig. They have mileage limitations and their service is usually good.

I went on the Ford build site. 2022 F350 Supercab XLT SRW Chassis cab with the stuff I would like. It was slightly cheaper then the low mile 2018 F350 SC pickup I came across.

Good point on the municipal stuff.

 

[Ninelitetrip]

Our '10 is the same in a diesel and factory snow plow front spring, deck and slide in Granby.

At that time (2010MY) C&Cs differences to PUs included: reaf leaf pack (shorter length, more leaves - 10 on ours), rear shock orientation (same, not bias and a bit shorter) and incl'd rear sway bar. All that should make a difference, esp the rear spring pack.

Gotta say for us, highway and FSR, stock was fine at max gvw. I only had springs reworked after added a front winch (was bottoming out) and for lift. And tires for well, tires.

Again, depends on application and wants. But for us, was worth trying out of the box first. Shocks you know you'll prob change out eventually.

Thanks for that.