Suspension advice for F250 6.7

[bwag]

I have a 2020 F250 6.7 diesel superduty with the camper package. Installing a lift/level kit up front and leaving the rear alone since it has an extra leaf which is part of the camper package.

I'm hoping the rear won't sag at all by sliding in a new Hawk weighing 1679 lbs. It's not getting installed until September.

Anyone running a similar set up that can advise if you had to do anything to your rear suspension prior to sliding in the new camper?

 

[patrkbukly]

2017 F250 Gas. Stock suspension and camper has never been off.

 

[bwag]

2017 F250 Gas. Stock suspension and camper has never been off.

Nice set up! Gas has the bigger payload. The extra leaf in the rear of my 6.7 which is included in the camper package will help, I'm hoping enough for no sag.

 

[patrkbukly]

Nice set up! Gas has the bigger payload, the extra leaf in the rear included in the camper package will help, I'm hoping enough for no sag.

I didn't know that.
I think you will be perfectly fine.

 

[SuperDutyFWC]

The extra leaf doesn't provide lift, it provides less sag under heavier weights. That may sound counter-intuitive, but what it means is the the overload only comes into play when there is significant weight in the back, causing sag to the point the frame begins to rest on the overload. You'll still get the same amount of sag or squat in the rear as if there were no overload though because your camper will cause the rear to sag just enough that it doesn't touch the overloads. There is a couple of inches of sag before the overloads come into play, and you'll still get that amount of sag. So, you'll notice it, it will sag, you'll squat in the rear compared to the front with a leveling kit.

I fought this same issue. I put the camper on my F250 and it sat almost level, with the camper in the bed. I thought I'd like a little more lift in the front, a leveling kit. It gave me between 2" and 2.5" of lift in the front, which ended up putting me nose high by about 1.5". Now I need to lift the rear by 1.5" to get it level again.

Consequences, my lights need to be adjusted driving at night, it looks weird, if I hook up a trailer it really sits nose high. If I wanted it level with stock sized tires, and were to do it over again I'd definitely not have lifted the front at all. It rode "right" and with the stock F250 suspension with the camper installed. I want a little lift though for my taller tires, so lifting the rear is probably exactly where I want it to be, with what I will end up with.

BTW, I'm using all Old Man Emu suspension parts to lift it, an advertised 2" lift.

 

[bwag]

The extra leaf doesn't provide lift, it provides less sag under heavier weights. That may sound counter-intuitive, but what it means is the the overload only comes into play when there is significant weight in the back, causing sag to the point the frame begins to rest on the overload. You'll still get the same amount of sag or squat in the rear as if there were no overload.

I fought this same issue. I put the camper on my F250 and it sat almost level, with the camper in the bed. I thought I'd like a little more lift in the front, a leveling kit. It gave me between 2" and 2.5" of lift in the front, which ended up putting me nose high by about 1.5". Now I need to lift the rear by 1.5" to get it level again.

Consequences, my lights need to be adjusted driving at night, it looks weird, if I hook up a trailer it really sits nose high. If I wanted it level with stock sized tires, and were to do it over again I'd definitely not have lifted the front at all. It rode "right" and with the stock F250 suspension with the camper installed. I want a little lift though for my taller tires, so lifting the rear is probably exactly where I want it to be, with what I will end up with.

BTW, I'm using all Old Man Emu suspension parts to lift it, an advertised 2" lift.

Thanks for the response. That's the way I understood the rear springs added in the camper package, no lift just help with the load. I'm doing a carli 2.5 commuter lift in front, I spoke with the Carli rep and he said I could consider 3-4 inch block in the rear as the commuter lift will bring it in his words "dead nuts level". I'm going to run 35" tires so I wanted the lift.

I'm also going to ask the lift shop if they can leave a little rake in also going to check to see if they have blocks. I've also heard super springs are an option.

Are you running a Hawk in your super duty and is it a diesel with the camper package?

 

[SuperDutyFWC]

You know what I forgot all about the rear block, so my first post was a little off-base. Sorry. I have an F350 block in the rear, meaning a 4" block in the rear (stock is 2") and it still squats with the Hawk.

More specifically, details: F250 4x4 crew cab with camper package, gas. I added F350 rear blocks and 2" springs in the front. So, the way it really works out is I have a 2" lift front and rear, over the stock suspension. BTW, there is more than enough room for 35" tires, and I'll probably go to 37" tires next.

However, loaded with the Hawk, it squats in the rear by 1.5". I measured fender to hub and it's 1.5". I'm installing 2" springs, with the 4" F350 rear blocks and hope it'll sit almost level, just a little rake so that when I pull my boat or put my motorcycle on the rear hitch carrier that it'll sit level.

With the Hawk loaded, right now, the frame "almost" rests on the overloads, and it does hit the overloads when I'm going over any sort of bump, driveway approach, or off road.

 

[bwag]

SuperdutyFWC, what 2" springs are you looking at? I called CJC offroad, they do a lot of installs including some with four wheel campers, guy on the phone basically said my best option would be air bags since I'm not leaving the camper on full time. He also said no matter what, I'm going to get some sagging in the back if only springs/blocks are used which I understand, I don't think I was clear enough with him as to how much in terms of inches/blocks or springs I would need to counter that.

He seemed against going the spring/block route to compensate for sag. In his words the ride quality of my truck would be the same with the airbags installed and no camper on vs putting more spring/block in which would affect ride quality with no camper in the bed.

I had airbags on my Tacoma, I just didn't like how much that truck swayed and felt soft however it was way overloaded compared to what my new set up will be. So maybe airbags wouldn't be as bad?

 

[SuperDutyFWC]

I bought Old Man Emu (OME) components. In my opinion they are the best suspension products, mass produced "kit", in the world. They (used to) only offer a 2" lift, max (for the US-market they've added taller lifts for certain vehicles), because in Australia your vehicle would be considered "off road only" if it was lifted more than 2". So, they produce the highest quality parts, with just about the least amount of lift. They manufacture shocks that work with the springs to provide the absolute best ride of any suspension company. Also, they will ask whether you have a medium load or heavy load because their springs are manufactured depending on whether you're driving a next-to-stock vehicle, or an overlanding rig. They are not a piece-meal kind of off the shelf, what works for one works for all, kind of company. Yeah, I think pretty highly of them.

So, I purchased stock F350 blocks. Basically, my F250 has F350 suspension. I then added, or will add, OME suspension. I've got the front springs and shocks installed and will install the rear leafs and shocks when I've got a free weekend.

Airbags and springs are two different things, designed for two different outcomes. I think the shop you called gave you some insufficient advice. Springs don't worse the ride, necessarily. It's just that most US buyers are buying crappy aftermarket springs designed solely for ride height and not ride quality. A good spring and shock combo increase ride quality, and may provide additional height. He probably sells "lift" kits.

 

[Stan@FourWheel]

bwag


We see a lot of trucks come through here.

I have seen a lot of lifted trucks with campers on them.

Seems like the lifted trucks also sag (squat) more with a camper on, than a truck with stock ride height.

A fully loaded Hawk, on a stock Ford F-250, CrewCab, Short Bed Diesel will most likely squat.

Especially if you lift the front.

Adding set of Firestone Ride-Rite Air Bags might be a good idea to keep the truck level and looking good when the camper is on.

We bagged all of our trucks here, even the lifted trucks. Has been working out great.

Hope this helps.

 

[bwag]

bwag


We see a lot of trucks come through here.

I have seen a lot of lifted trucks with campers on them.

Seems like the lifted trucks also sag (squat) more with a camper on, than a truck with stock ride height.

A fully loaded Hawk, on a stock Ford F-250, CrewCab, Short Bed Diesel will most likely squat.

Especially if you lift the front.

Adding set of Firestone Ride-Rite Air Bags might be a good idea to keep the truck level and looking good when the camper is on.

We bagged all of our trucks here, even the lifted trucks. Has been working out great.

Hope this helps.

Thanks Stan, I appreciate your input, you likely have seen more suspension setups related to Four Wheel Camper's than anyone else. I'm going to have the Firestone Air bags installed at the same time I do the lift.

 

[bwag]

SuperDutyFWC, thanks for your input! After making a phone call to another reputable shop and Stan providing his input, I'm going to do the air bags. What I like is that I can air them down when the camper is off the truck and get the normal driving characteristics out of the truck.

I did run old man emu add a leaf's on my Tacoma along with firestone airbags. I only drove it unloaded (no camper) for a week then had my Swift on full time. I do remember the rear of my truck was raised by the springs and it was a noticeable stiffer ride. I don't doubt the information you provided but can only pull from my experience.

The above being said, it's not an apples to apples comparison, a Tacoma with a payload of 1200 pounds is not an F250 Superduty 6.7 with a camper package. There's no doubt I was pushing the Tacoma at it's limit and beyond at times which was a known factor prior to my purchase. The F250 6.7 although having a less of a payload than an F250 gasser, is leaps and bounds above my Tacoma. I suspect the airbags won't be doing near the work on the F250 6.7 as they did on the Tacoma.

 

[mrpeepers74]

so im curious how air bags affect the suspension in rear.

I have a dana 80 on older ram 2500 with camper leafs. it still squats some with the airbags inflated. grandby mounted on flatbed.

so, with stock suspension, do you feel airbags make it bouncy or dampen the load on forest roads?

might be an amateur question, but i really dont understand how air bags affect ride quality with leafs.

 

[SuperDutyFWC]

Air doesn't compress very well, so you put a balloon between your frame and axle (spring) and adjust the amount of air in that rubber balloon to keep the frame from moving. You can increase the (air) pressure in the balloon and make it as hard as you want. The harder it is, the less your bed will move (squat). So, you put a load in the bed and increase the pressure until you have the ride height (or lack of sag) that you want.

 

[bwag]

so im curious how air bags affect the suspension in rear.

I have a dana 80 on older ram 2500 with camper leafs. it still squats some with the airbags inflated. grandby mounted on flatbed.

so, with stock suspension, do you feel airbags make it bouncy or dampen the load on forest roads?

might be an amateur question, but i really dont understand how air bags affect ride quality with leafs.

I can only speak for my Tacoma, but the Firestone bags inflated to 40psi would easily put a forward rake in my truck when I was headed for a trip. When the camper was dry I'd run about 15psi, I had Dakar OME add a leaf heavy duty springs in the rear along with fox suspension. I never took the camper off and the ride was fine going down the road, what I didn't like was the bounce over something like a speed bump or the sway if taken at an angle, dirt roads with some pot holes were fine bigger bumps not so much in terms of bounce.

My F250 has a camper package so it has an additional leaf spring in the rear as well as sway bar and some stuff up front. The load on this truck compared to my Tacoma is significantly less in terms of payload/GVWR to camper ratio, my hope is there will be less bounce/sway, if not then I'll have to look at other options.

Air doesn't compress very well, so you put a balloon between your frame and axle (spring) and adjust the amount of air in that rubber balloon to keep the frame from moving. You can increase the (air) pressure in the balloon and make it as hard as you want. The harder it is, the less your bed will move (squat). So, you put a load in the bed and increase the pressure until you have the ride height (or lack of sag) that you want.

That's a good description.

 

[CoreyTrevor]

I'm curious too about the ride with airbags when loaded. Do they have a really fast rebound once compressed, that overwhelms the shocks rebound damping? I've heard that airbags have a progressive spring rate vs leaf springs or single rate coil springs that have a linear rate.

So the airbag ramps up in stiffness at a faster rate than the springs? Or is that not correct?

Is that what the bounce over speed bumps is like?

 

[SuperDutyFWC]

I can't speak to the progressiveness of air bags except to say the rubber in which they are manufactured stretches, so that it may be "progressive". It may stretch in a progressive manner, as opposed to a linear one, but I don't know that.

Depending on the leaf springs, they can be multi-stage, although most probably aren't.

OME Dakar springs are usually dual-stage leaf packs. When unladen, the vehicle is largely riding on the primary stage. So, around town, unloaded you have a softer ride. Add weight and you get into the second stage that is load carrying.

Stock Super Duty leaf springs are dual or three-stage by the way. The stiffest, teeth-jarring, rear leaf springs come on the diesel model. If you have the diesel, your springs are three stage and STIFF.

 

[ntsqd]

The biggest problem with air springs is that they are not linear in spring rate. Say it takes 500 lbs. to compress them the first inch from ride height. I linear spring with compress a further inch from a second 500 lbs. being added. With an air spring it could take 700 lbs to compress it the next inch, and 1250 lbs added for the third inch. Linearity is actually not desirable, but the rate of the rising spring rate should be low, say less than 10%

Where this becomes a problem is damping the suspension, particularly in rebound. Damping that worked well with a 500 lbs/in spring rate will likely be under-damped with a 1250 lbs/in spring rate.

My own preference is to not lift a truck carrying a camper. We fit 35's on our stock ride height Ram. At one point I had wheels with the wrong offset on the truck, and that allowed the front tires to make occasional contact where they shouldn't have. It also went down the road like a drunken sailor. Getting the right offset (i.e. back to stock) on the truck cured both problems.

 

[CoreyTrevor]

That's what I was picturing. When the bags are really compressed they will rebound so fast that the shocks won't be able to control it.

A correctly designed and set up bypass shock would be a solution, being position and velocity sensitive, unlike normal shocks just being velocity sensitive.

That solution would get expensive just to deal with a cheap pair of airbags.

 

[bwag]

I only drove my Tacoma 2 weeks before sliding the camper in for 2 years and not taking it off. The rear end was too stiff unloaded. With my Tacoma which had fox shocks in the rear, Dakar extra leafs and firestone bags, when the camper was on, it didn’t bounce back too fast, in fact for me I felt it was too soft. That being said, I didn’t try different air pressure settings on the bags so maybe it was related to that but I felt like I was riding on marshmallows!

I’ve read on some forums about the camper package on the F250 6.7 making the unloaded ride unpleasant, call me crazy but I think it’s great. It’s stiff but not too stiff which is how my Tacoma was unloaded.

The lift is definitely give and take, regardless of the 2.5 Carli lift I’m doing bags or some other measure we’re going to be needed bottom line is payload on a diesel isn’t the same as a gasser.

I had my tires run on my Tacoma, I dealt with it but it got old real fast! My new rims will be 9” wide with 35x12.5 tires, and a 1mm offset, I think rubbing issues on F250’s with a 2.5” lift start at the -19 or greater offset, I don’t want my wheels sticking out that far or the rub which is why I went with a +1mm offset.