Removing LMTV suspension compression system

Recently acquired my first LMTV. Looking at the possibility of removing all of the hydraulics and air system connected to the suspension compression system to improve reliability and remove a little of the complexity.

Dont think I will ever use any of the suspension capability since I recently sold my C-130 and my C-17. (Crashed my C-141 last year so it is gone too)

Are there any reasons not to remove the suspension compression system??

All you can remove is two cylinders and some hoses, the contol valve and air-hydraulic power pack has to remain to lift the cab. Then you have to go buy appropriate caps to keep dirt out of the unused ports on the valves. Sounds like a lot of work with no benefit.

I have just joined the ranks of LMTV owners. I also foresee no need for the suspension kneeling system. One device I want to add is a hydraulic hoist to make loading the bed a little easier. Of course there was one made for these trucks but they seem a little hard to find.

My plan is to use the suspension control valve to power the hoist. Seems that would be easy to do, simply removing the hoses from the kneeling cylinders and route to the hoist cylinder. The kneeling cylinders themselves seem a little short on stroke but might be usable in a small home-made hoist.

Instead of remove, recycle!

Bob

Reuse is good!

If the hoist is not located very close to the pump panel it could be a challenge to control and place the load safely.

If you tee'd into the air circuit that powers the aux hydraulic pump you could turn the pump on easily but not reverse the hydraulic flow.

It might also be done on the hydraulic side at the control panel if the pump ON push valve was locking, similar to the cab bleed down valve. You could use a local hydraulic control valve at the hoist then.

I haven't looked at the auxiliary hydraulic system pressures or flow rates yet but may get a chance this weekend.

All in all, nice electric winch could be the simpler solution!

Cool idea though. Might need to modify the hand crank hoist I have already acquired.

My plan is to split the lines to control them individually then use them as "suck down winches" (parlance of the rock crawler crowd). When the truck is on a side slope, activate the cylinder on the high side to "suck down" the suspension on that side. It might be just enough to avoid a tip over, and aid traction.

olly hondro said:

My plan is to split the lines to control them individually then use them as "suck down winches" (parlance of the rock crawler crowd). When the truck is on a side slope, activate the cylinder on the high side to "suck down" the suspension on that side. It might be just enough to avoid a tip over, and aid traction.

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Twas exactly my thoughts too. but note... it appears they are not attached to anything until you stop and do that manually. ... then you can suck her down. Another words to do what we are thinking.... will take some additional mods.

NDT said:

All you can remove is two cylinders and some hoses, the contol valve and air-hydraulic power pack has to remain to lift the cab. Then you have to go buy appropriate caps to keep dirt out of the unused ports on the valves. Sounds like a lot of work with no benefit.

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It's worse than that, the hydro manifold uses a common return, so if a plug is missing fluid will dump even if that is not the circuit selected.

coachgeo said:

Twas exactly my thoughts too. but note... it appears they are not attached to anything until you stop and do that manually. ... then you can suck her down. Another words to do was we are thinking.... will take some changes.

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Yeah, something clever with limit straps perhaps.

aleigh said:

It's worse than that, the hydro manifold uses a common return, so if a plug is missing fluid will dump even if that is not the circuit selected.

Click to expand...

Now that's a horse of a different color....the thought was to have the control in the cab just for that circuit.....will have to burn a few more grey cells.

To do what you are thinking I dont think those cylinders will have enough travel to allow you to hook them up before entering rough terrain and still have full suspension travel and the ability to suck down one side to a useable ammount.

The other factor is how valuable will this really be. What rolls a vehicle over on a hill? The CG(or associated momentum) moves outside the points of lift on the downhill side and the triangle with the CG at the top rolls over. Compressing the suspension on one side(and only at the front) is not going to really extend it on the other so I dont think it is going to move the CG very much in relation to that downhill side contact point.

It might get you a degree or two more side angle tollerance? You could probaby achieve the same effect by altering tire pressure side to side. If it is down to traversing a hill within a degree or two of my rollover angle, well I am probably not going. If I was setting up a vehicle to squeek by places like this, I would probably build a re-enforced triangle structure that goes above the CG and run a winch cable up thru a roller fairlead to be pulled out to a ground anchor on the highside to get past the bad spots...IMO I think it would be more effective...


As for using the AOP for a load handling crane, the AOP is really low volume and was only intended for occasional use. look at how long it takes to raise the cab... You could probably make one work, but I would not want to have to use it every day You could fab up a A frame and electric winch that would probably work a lot better and have more capacity at a faster speed...

As always my .02

to ressurect an old thread...my suspension raise/lower rotory valve is leaking more fluid than Joe Biden's head... can the valve be bypassed/disabled by simply plugging the hydraulic lines that go into the manifold?

BERZERKER888 said:

to ressurect an old thread...my suspension raise/lower rotory valve is leaking more fluid than Joe Biden's head... can the valve be bypassed/disabled by simply plugging the hydraulic lines that go into the manifold?

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Have you tried converting it to electric or other green energy? Because YOU VILL BE!!!

/snork

BERZERKER888 said:

to ressurect an old thread...my suspension raise/lower rotory valve is leaking more fluid than Joe Biden's head... can the valve be bypassed/disabled by simply plugging the hydraulic lines that go into the manifold?

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No, it gets fluid internal to the valve block. It shouldn’t be getting any fluid if the 3way selector isn’t switched to that position, so maybe that valve is also leaking internally…

Anybody want to sell your suspension compression hydraulics LMK.

GENX said:

Anybody want to sell your suspension compression hydraulics LMK.

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Cant u just swap the lines on the selector manifold

chucky said:

Cant u just swap the lines on the selector manifold

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I am looking for two kneeling cylinders and the shackles.

GENX said:

I am looking for two kneeling cylinders and the shackles.

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i thought yout selector valve was leaking so to just swap lines to an unused valve

GENX said:

I am looking for two kneeling cylinders and the shackles.

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Just took off the passenger side one, will have the driver side off by mid-next week. Are you still looking?

RandomThinker said:

Just took off the passenger side one, will have the driver side off by mid-next week. Are you still looking?

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Maybe the drivers side is the hard one, I had to make a tool to reach the bolts on that side…

Yea I'm waiting for my crowfoot wrenches to come. Hopefully they make it.