Rear suspension travel F350

[RLDSL]

Would anyone happen to know how far the rear axle travels from center on a 92 f350 dually , that would be center up and center down?
I just installed a set of air bags and I'm rigging an automatic leveler valve like semi trucks have and I'm trying to figure out how to rig the linkage.

Thanks----Robert

 

[LCAM-01XA]

IIRC mine is about 4-5" in each direction, at least this is what the shocks allow for. I use 4x4 shocks cause the 2wd ones are too short for me, and with the truck empty the axle sits right in the middle of the shock stroke.

 

[RLDSL]

THat seems like a pretty fair allowance. That ought to work for figuring purposes
Thanks

 

[LCAM-01XA]

Rob, the 2wd shocks are shorter than the 4x4 ones and IIRC they also have a a bit less stroke, so methinks that if you plan for linkage travel of 8" you should be good. I ain't familiar with the big-truck self-leveling setups, is there some sort of electronic control module for the air bag solenoids? A while back I was thinking of using the factory air-ride system off a Lincoln only with larger solenoids to match the heavy-duty truck air springs...

 

[RLDSL]

Rob, the 2wd shocks are shorter than the 4x4 ones and IIRC they also have a a bit less stroke, so methinks that if you plan for linkage travel of 8" you should be good. I ain't familiar with the big-truck self-leveling setups, is there some sort of electronic control module for the air bag solenoids? A while back I was thinking of using the factory air-ride system off a Lincoln only with larger solenoids to match the heavy-duty truck air springs...

It's a big lever operated mechanical valve, no electronics. You attach it to the frame and then attach a pivot point to the axle somewhere , then hook them uop with an adjustable linkage armthat you can screw to a neutral position when it is where you want it at level. You need to have a compressor rigged on a pressure switch for shutoff with an accumulator tank and then the valve if the axle compresses too far will let more air in, and if it drops too far it exhausts air off.

 

[pybyr]

Would anyone happen to know how far the rear axle travels from center on a 92 f350 dually , that would be center up and center down?
I just installed a set of air bags and I'm rigging an automatic leveler valve like semi trucks have and I'm trying to figure out how to rig the linkage.

Thanks----Robert

Could you please provide/ share all the photos that you possibly can on what you did and how you did it?

I am very interested in what you developed and installed for linkages, places you tie into the frame (or were you able to use original spring hangers?) and anything else that shows design and install details.

In addition to wanting to see/ understand the layout of your main links/ bags, etc., I'd be really interested in seeing photos or sketches of where you plan to put the leveler valve (physical location) and how/ where the leveler valve ties into the air lines. I know only a little about how leveling systems work in this application (I understand them better in other applications) so I'd like to get a better understanding of what you are up to/ how you will make it work.

Thanks very much

Trevor

 

[RLDSL]

The way mine is going in won't be tha same as a regular truck because I'm welding the leveler bracket to the subframe for my Western Hauler bed ,I'm connecting the lower eye to the bracket that the spring ubolts go through
The bags are just helper bags so they are top mounted, but not the usual kit jobs because that setup wouldn't work with my bed. I'll try to get some pics later

 

[LCAM-01XA]

And how sensitive is that valve? Cause the Lincoln electronic box is programmed to ignore axle frequent oscillations such as those that occur as the vehicle drives over uneven pavement, the system can be made to work without this "brain" but then every time you go over a bump the height sensors would fire the compressor and dump valves, which is obviously not a good thing. The "brain" also accounts for doors opening and closing (ride height will not be adjusted if doors ain't fully closed), but for our purposes this is really not too important.

So with the mechanical valve, what if you happen to be driving over some bouncy dirt road - would that make the valve put air in and out of the bags constantly?

 

[RLDSL]

And how sensitive is that valve? Cause the Lincoln electronic box is programmed to ignore axle frequent oscillations such as those that occur as the vehicle drives over uneven pavement, the system can be made to work without this "brain" but then every time you go over a bump the height sensors would fire the compressor and dump valves, which is obviously not a good thing. The "brain" also accounts for doors opening and closing (ride height will not be adjusted if doors ain't fully closed), but for our purposes this is really not too important.

So with the mechanical valve, what if you happen to be driving over some bouncy dirt road - would that make the valve put air in and out of the bags constantly?

You would have to have some really bad shocks for it to be flouncing enough to start fluttering. I've had airride systems on washboard roads and they don't start dumping the tank

 

[LCAM-01XA]

So I guess then they are not too sensitive to height changes? How much you expect the rear will have to sink down when loaded before the valve catches it and brings it back up, like 1" maybe?

 

[RLDSL]

So I guess then they are not too sensitive to height changes? How much you expect the rear will have to sink down when loaded before the valve catches it and brings it back up, like 1" maybe?

I'll have to play with the adjustments basically but it shouldn't let it sink down more than 2" . There are 2 holes in the arm for different leverage adjustments and I can drill in different locations if needed or lengthen the arm any of which will change the rate . I just won't know how it reacts till I fire it up THis is a high pressure valve and it doesn't respond without some presssure to it so I can't just push a blow gun up and test and I don't want to ruin any compression fittings

 

[Goofyexponent]

The way mine is going in won't be tha same as a regular truck because I'm welding the leveler bracket to the subframe for my Western Hauler bed ,I'm connecting the lower eye to the bracket that the spring ubolts go through
The bags are just helper bags so they are top mounted, but not the usual kit jobs because that setup wouldn't work with my bed. I'll try to get some pics later

The only problem you might have here is if you only use one valve for the bags is this.

If you put the arm on only one side to adjust height, and your truck gets in an off camber situation, it won't self level like a big truck.

i would try and use two valves to control the bags independantly if possible.

 

[LCAM-01XA]

Goofy, excellent point!

 

[Goofyexponent]

Goofy, excellent point!

Thanks. I used to run a Western Star with Neway air ride......gerat system for the road, but put one axle on the curb and that's it unless you got an axle lock.

You can pull these valves from almost anything with air ride in it...tractor cabs with air ride cabs, suspension and lift/pusher axles.

The suspension valves are going to be larger, faster acting and flow a pile more air!!

I know for a fact that most Kenworth air ride trucks use an 8 bag suspension system in the rear tandems that you could pull stuff from if need be.

Ditch the push lock synflex connections for brass ferled connections for a good, permanent seal!

 

[RLDSL]

Stiff as my axle is already I can probably get away with the one valve. It just spent the last 2 weeks up in the air with the axle on a jack and you can jack one side and the other goes with it.. then the whole truck goes with it, still wouldn't be that big a deal to mount another. for twins. Just wish That would have come up before I put the wheels on.
Around here the darn things are cheaper new than at the boneyard. I got one for $44 brand new, boneyard wanted more than that. I'm going to go ahead and pickup a linkage rod with the eyes at the truck parts house.Was going to make one, but might as well just buy one to get the easy adjustment