Rear Suspension Mod's For Big Blue?

[Gary Lewis]

That was my thought too. They do not ride badly at all and wear seems fantastic, I will get a picture of the front tread later today. One item I found in the past, DRW tire ratings are lower per tyre than SRW, probably due to greater heat buildup with the tyres so close together.

Better more rather than less.

I didn't realize that the same tire used in DRW applications is rated less than in SRW app's. Perhaps that's the 115/112 bit?

[85lebaront2]

I didn't realize that the same tire used in DRW applications is rated less than in SRW app's. Perhaps that's the 115/112 bit?

Don't know, my last set (Sears) had the load ratings as xxxx single and xxxx dual. As long as I have a minimum of 1850 lbs per tyre on the rear I am fine. These were actually a good price and readily available and the company has the equipment to handle the Alcoa rims without damaging them and can balance them.

[Nothing Special]

Coming a little late to this party. I had Firestone Ride-Rite air bags on my '95 F-150. After I bought that truck I got a slide-in camper and the truck didn't handle that weight very well. Rather than get the right truck for that load I put air bags and load range E tires on a half-ton. Note that I do not recommend that (that would be Wrong). But it did work out pretty well. The truck handled the weight quite well. So I'd say that overall you have a good plan.

I never noticed any significant wear from grit or anything (not that I did any off-roading with that truck). But the bags did have sort of an accordion pleat to them that could have trapped grit when the suspension was compressed a bit.

Lack of suspension travel was a bit of an issue in my F-150, but I don't know if it would matter in an F-250HD. I tried to set mine where the air bags would bottom about where the bumpstops hit, and set like that the air bags were the limiting factor in droop. that never seemed like a good thing, but again, without taking the truck off-road it wasn't really an issue.

You can set up air bags do work differently based on how you plumb them. I really wanted roll stiffness in my 3/4 ton F-150 so I didn't connect them together. That meant I had to inflate them separately, but it also meant that air couldn't transfer from one side to the other, which was good in my situation. On the other hand, I've thought about using air springs on a dual axle trailer with BIG air lines connecting the front and rear bags on each side together (but still having right separate from left). That should give the same sort of effect as the equalizing shackle set-up on leaf sprung trailers. By connecting right and left air bags you could get more or less roll stiffness by changing the size of the air lines. Just some rambling thoughts.

[Gary Lewis]

Coming a little late to this party. I had Firestone Ride-Rite air bags on my '95 F-150. After I bought that truck I got a slide-in camper and the truck didn't handle that weight very well. Rather than get the right truck for that load I put air bags and load range E tires on a half-ton. Note that I do not recommend that (that would be Wrong). But it did work out pretty well. The truck handled the weight quite well. So I'd say that overall you have a good plan.

I never noticed any significant wear from grit or anything (not that I did any off-roading with that truck). But the bags did have sort of an accordion pleat to them that could have trapped grit when the suspension was compressed a bit.

Lack of suspension travel was a bit of an issue in my F-150, but I don't know if it would matter in an F-250HD. I tried to set mine where the air bags would bottom about where the bumpstops hit, and set like that the air bags were the limiting factor in droop. that never seemed like a good thing, but again, without taking the truck off-road it wasn't really an issue.

You can set up air bags do work differently based on how you plumb them. I really wanted roll stiffness in my 3/4 ton F-150 so I didn't connect them together. That meant I had to inflate them separately, but it also meant that air couldn't transfer from one side to the other, which was good in my situation. On the other hand, I've thought about using air springs on a dual axle trailer with BIG air lines connecting the front and rear bags on each side together (but still having right separate from left). That should give the same sort of effect as the equalizing shackle set-up on leaf sprung trailers. By connecting right and left air bags you could get more or less roll stiffness by changing the size of the air lines. Just some rambling thoughts.

That's my thinking as well - separate fills so it gives as much roll-prevention as possible. And, that allows for inflating/deflating one side when crossed-up on the trail to get traction. But, for that to be effective you have to have soft suspension. As it is, Big Blue's suspension is so stiff there's little movement.

The bags I'm looking at have bump-stops in them, but that might be a limitation as it minimizes the available travel. So, if I could rely on the stock bump-stops then I wouldn't need the top-of-the-line bags.

And, there's the stock spacer that comes on the 4x4 trucks, which I might take that out depending on how much the truck sits down with softer springing. I say that because Air Lift says there needs to be 5 - 7" between the brackets, and 7" is better than 5". I'll have to check, but right now I'm sure there's more than that.

[85lebaront2]

That's my thinking as well - separate fills so it gives as much roll-prevention as possible. And, that allows for inflating/deflating one side when crossed-up on the trail to get traction. But, for that to be effective you have to have soft suspension. As it is, Big Blue's suspension is so stiff there's little movement.

The bags I'm looking at have bump-stops in them, but that might be a limitation as it minimizes the available travel. So, if I could rely on the stock bump-stops then I wouldn't need the top-of-the-line bags.

And, there's the stock spacer that comes on the 4x4 trucks, which I might take that out depending on how much the truck sits down with softer springing. I say that because Air Lift says there needs to be 5 - 7" between the brackets, and 7" is better than 5". I'll have to check, but right now I'm sure there's more than that.

As discussed earlier, further tyre pictures:

[Gary Lewis]

As discussed earlier, further tyre pictures:

Yup, 2680 SRW vs 2470 DRW. But you still have 620 lbs/tire of reserve.

[85lebaront2]

Yup, 2680 SRW vs 2470 DRW. But you still have 620 lbs/tire of reserve.

FWIW, here is the left front after 3 1/2 years and quite a few round trips to Newport News VA and Pittsville MD.

[Gary Lewis]

FWIW, here is the left front after 3 1/2 years and quite a few round trips to Newport News VA and Pittsville MD.

Looks like it is wearing quite evening, Bill. But, what are those curly things in the pic? Doesn't a "real truck" have the buckboard style leaf springs?

Seriously though, why did Ford think a 4wd F250/350 needed leafs and a 2wd could use coils? I've never understood that when that wasn't the case in the F150's. Was the radius arm not up to the task of keeping a heavier front axle in check?

[85lebaront2]

Looks like it is wearing quite evening, Bill. But, what are those curly things in the pic? Doesn't a "real truck" have the buckboard style leaf springs?

Seriously though, why did Ford think a 4wd F250/350 needed leafs and a 2wd could use coils? I've never understood that when that wasn't the case in the F150's. Was the radius arm not up to the task of keeping a heavier front axle in check?

First, in 1986 the crew cab DRW trucks could not be ordered as a factory 4WD, In fact I am not sure any 1986 F350 DRW truck could be factory 4WD, Ford did sell a number of cab & chassis 4WD models, but they have the Dana 60 rear and a narrower track.

Second, if I had wanted 4WD, I would have opted for a mono-beam front end with the Dana "king pin" style as it has cone roller bearings top and bottom so no ball joints.

As for "real trucks" lets not talk about Blue Jeans, with its FWD sedan front end, or "dad's" with the twin traction beam coil spring system.

I like the ride the coils give up front having driven 4WD F250s and my 1958 F100, the scout camp cornbinder, and any number of Mxx USMC trucks from the old Jeeps to a 5 ton wrecker.

If I really wanted a 4WD truck, I would try to find an old M37 Dodge built 3/4 ton, either build a bigger MOPAR flat head for it or shove a 318 Polyshere head in there, power steering and better brakes. Those things I think could climb a wall straight up if you could get traction.

[82F100SWB]

Looks like it is wearing quite evening, Bill. But, what are those curly things in the pic? Doesn't a "real truck" have the buckboard style leaf springs?

Seriously though, why did Ford think a 4wd F250/350 needed leafs and a 2wd could use coils? I've never understood that when that wasn't the case in the F150's. Was the radius arm not up to the task of keeping a heavier front axle in check?

Looking at the shape of the end cut and the thickness of the leaves, I would be inclined to believe that those springs in big blue aren't factory pieces at all and that may well explain your ride issue.