14 replies to this topic

[ntsqd]

Reason that I asked where the O/L's are located is because there is a trick with under-rider types to bring them into play earlier, that is easily reversed for when the camper is not in the bed.

 

I still don't understand needing air bags on a 3/4t truck. We have one such, no air bags, and the O/L's are deliberately very late in coming into play. No issues, no exaggerated sway, truck sits level with the camper in the bed. As far as I know they are OEM rear springs.

[Advmoto18]

 

 

I still don't understand needing air bags on a 3/4t truck. We have one such, no air bags, and the O/L's are deliberately very late in coming into play. No issues, no exaggerated sway, truck sits level with the camper in the bed. As far as I know they are OEM rear springs.

 

Interesting comment regarding your O/L springs.  I wonder if they are after-market?

 

I'm on my 4th Super Duty and all have squat some under a heavy load, camper, gravel, etc..  And all have had the enhanced payload (O/L spring) option or the OME suspension upgrade with overload spring installed.  And as springs age, with a camper in the bed full time, the springs will eventually take a set to that weight and sag even when the camper is removed.  With my Hawk wet and fully loaded, my overload springs (and I have the heavy payload option on my F-350) will just touch the spring's frame mounted rubber bump pads, front and rear.  The air bags simply allow me to return the spring tension to the unladen position which is the most comfortable ride.

 

I've emailed/discussed spring pack ideas with Dan at Carli Suspensions quite a bit.  It has been an education.  Sadly Carli does not offer spring packs designed for heavy laden trucks 24/7/365.  But there are vendors who CAD spring packs based on a payload figure.  If your payload varies substantially (camper in bed a limited amount of time), then you will have to seek a compromise solution with a custom spring pack.

 

I opted for the 4x4 package (not FX4) so I could install the Helwig sway bars F/R and a few other more robust after-market accessories compared to the FX4 offerings.  Sway without the rear bar was very noticeable.  After installing the Helwig, no sway, at all.

 

My Wells Cargo trailer is a tandem wheel 7000# GVWR trailer.  While I don't push trailer GVWR, a total weight of 4000# loaded for a trip would not be an unrealistic guess.  When loaded with my BMW R1200GS and KTM 350 (BMW in more forward chock) the tongue weight is 440#.  

 

Must I use air bags?  No, but I much prefer the truck riding level at all times, so, I use air bags.

Edited by Advmoto18, 01 April 2018 - 03:21 PM.

[ntsqd]

As best as we (that being myself and my friend & local 4x4 shop's owner Ruben) know they are all OEM springs. When he had the truck in to re-gear it and & add a rear LSD I asked him to do his mod to the O/L's. They now don't start to do much until the 'normal' springs are very close to being flat and the tips of the O/L's won't touch until the mains are slightly inverted. Dramatically reduced the "buckboard-like" ride.

EDIT: This is not a Ford, it is a '95 CTD. And the cliche' about nice body too bad it comes wrapped in a Dodge is mostly true; given the time I'd scrap the body and install a Ford '77-'79 SuperCab

Edited by ntsqd, 01 April 2018 - 05:19 PM.

[Advmoto18]

I should have mentioned, I (and I pretty sure SMLOBX as well) installed the Bilstein 2" front leveling kit (Bilstein coils springs and Rancho RS9000XL shocks).  This kit levels the front of the truck to the rear, unladen.  Thus, if any load is added to the bed, the rear will squat a bit relative to the front.  But I added a Trail Ready front bumper and a Warn 16.5 Ti-S winch so the rear squat is about an inch lower than the front with the Hawk camper loaded out for an adventure.  40 psi in the air bags puts the rear ~.5" higher than the front, pretty much the deflection of the spring packs if the truck were unladen.

[klahanie]

I'm on my 4th Super Duty and all have squat some under a heavy load, camper, gravel, etc..  And all have had the enhanced payload (O/L spring) option or the OME suspension upgrade with overload spring installed.  ...

 

....Sadly Carli does not offer spring packs designed for heavy laden trucks 24/7/365.  But there are vendors who CAD spring packs based on a payload figure.  If your payload varies substantially (camper in bed a limited amount of time), then you will have to seek a compromise solution with a custom spring pack.

 

For a load of gravel or a big heavy camper the single oem top overload leaf will help but imo it won't do a whole lot. Just as a fwiw, a spring shop should be able to make or acquire a multi leaf overload pack (the F350 dually has 2 leafs for eg). this can be set to mostly only come into play for when that big load is being carried, effectively giving a two stage rate. Actually a bit better than that because I think the overload contact pads are designed to contact in series (ie say, front first, then front and rear) And I guess if you also had a bottom overload that ntsqd mentioned that could make three stages.

 

 

btw that 9 leaf main pack was oem for srw cab and chassis, plus originally had a single top O/L.

 

Of course our trucks have the top O/L contact pads, a design for heavier loads I believe. The F150 and down don't (I think) but then again our little pop ups are pretty light weight...

 

If I was 24/7 I'd want to eliminate any top O/L's and have the main pack reworked to be rid of any possible contact pad slap when off highway