Relocate batteries and fuel tank inboard

[scottmandu]

So I've got this hair brained idea to relocate all the outboard equipment (batteries, fuel tank, and air tanks) between the frame rails, or in the case of the air tanks, fabricate a roll bar from steel pipe that also functions as air reservoirs.

The space is there however my concern is the amount of frame flex experienced when off roading. Does anyone know if frame movement is appreciable in off roading situations. My attempts to demonstrate frame movement all have failed.

 

[coachgeo]

my only experience with large truck chassis is older Unimogs and that's a different animal so take below with big grain of salt. Hopefully it will help somehow.

Are you going to have stock troop/cargo bed on it? I'd think the frame rail of that bed adds substantial stiffness to the chassis.

Having not looked at the Chassis design of these...... is it a typical Ladder frame? If so the far ends are what gets twisted the most and the center the least.


Is the cab or engine and tranny mounts designed for chassis to flex below them or to flex along with chassis? If not there is a hint that you'll have no issues with inboard mounting.... especially if you attach to only one rail of chassis as was done when mounted outboard. (or fixed one rail and floating/hinged on other)

Are there any in action or construction vids/images of Expedition Rigs based on Steyr or LMTV that might offer a hint or two?

 

[Lmtv772]

Of all the money I have seen some people throw at their FMTV and projects they have started, you come with with the wonkiest ideas and oddest things to do.
Maybe you should start with the more obvious things to fix on a FMTV. Which reminds me...

 

[Shark Bait]

So I've got this hair brained idea to relocate all the outboard equipment (batteries, fuel tank, and air tanks) between the frame rails, or in the case of the air tanks, fabricate a roll bar from steel pipe that also functions as air reservoirs.

The space is there however my concern is the amount of frame flex experienced when off roading. Does anyone know if frame movement is appreciable in off roading situations. My attempts to demonstrate frame movement all have failed.

Please elaborate on the reasoning for relocating?

Dave

 

[Ukraine Train]

Please elaborate on the reasoning for relocating?

Aerodynamics.

 

[scottmandu]

Please elaborate on the reasoning for relocating?

Dave

I nearly ripped off the battery box and fuel tank going over some tall and narrow berms. Luckily the ground was soft and the truck just plowed through the dirt. You can see where the air tank bracket was shifted over on the mounting bolts.

I'd also like to use the outboard space for bolt on accessories like aux fuel/water tanks or cargo compartments.

 

[Shark Bait]

Not much flex at all.

Dave

 

[dilligaf13]

Of all the money I have seen some people throw at their FMTV and projects they have started, you come with with the wonkiest ideas and oddest things to do.
Maybe you should start with the more obvious things to fix on a FMTV. Which reminds me... Do you own an LMTV now and is it in your possession?
Otherwise I can think of a couple of cool projects one could do on a Saturn V platform. But what's the point? I will never own one.

DaveI nearly ripped off the battery box and fuel tank going over some tall and narrow berms.

So I guess the answer would be yes, he does own one....

 

[mkcoen]

So I guess the answer would be yes, he does own one....

His response was to the 2nd poster coachgeo who I believe just purchased a truck and hasn't picked it up yet.

 

[Lmtv772]

His response was to the 2nd poster coachgeo who I believe just purchased a truck and hasn't picked it up yet.

That's correct.

 

[Ukraine Train]

In response to the original question, an option might be to make a sub-frame of sorts for the tanks, batteries, etc., and mount it with large, squishy, isolators to the main truck frame. Or even use links with heim joints that allow the truck to twist around the subframe but not let the subframe bounce around... kind of like an axle, I guess.

 

[Terrh]

Mounting the air tanks elsewhere doesn't seem like a bad idea, but mounting the batteries inboard sounds like a bad time when you need to access them.

 

[aleigh]

View attachment 618174Not much flex at all.

Dave

Is that with the anti-sway bar attached? Because...

 

[Overdrive]

View attachment 618174Not much flex at all.

Dave

is that with or without the rear sway bar connected... If you want flex your going to have to uncouple the sway bars (Offroad only). Jeep tip

OD

 

[Shark Bait]

Is that with the anti-sway bar attached? Because...

Attached.

 

[dubblosvn]

So I've got this hair brained idea to relocate all the outboard equipment (batteries, fuel tank, and air tanks) between the frame rails, or in the case of the air tanks, fabricate a roll bar from steel pipe that also functions as air reservoirs.

The space is there however my concern is the amount of frame flex experienced when off roading. Does anyone know if frame movement is appreciable in off roading situations. My attempts to demonstrate frame movement all have failed.

Did you end up making this work out? I'm looking to do something similar for the same reasons.

 

[Third From Texas]

Did you end up making this work out? I'm looking to do something similar for the same reasons.

There's a used here who did this I think. He's got the truck with the CAT yellow rool bar and cage (name escapes me at the monemt..."Olihondro" or something?)

 

[coachgeo]

There's a used here who did this I think. He's got the truck with the CAT yellow rool bar and cage (name escapes me at the monemt..."Olihondro" or something?)

he moved the tanks...(air and fuel).. dont recall if he used his roll system (ROP) for any kind of tanks. I doubt you could ever drive one on the road if you used ROP for tanks cause you would never pass DOT.

 

[Third From Texas]

he moved the tanks...(air and fuel).. dont recall if he used his roll system (ROP) for any kind of tanks. I doubt you could ever drive one on the road if you used ROP for tanks cause you would never pass DOT.

I've thought about some sort of skid plate/protection for the fuel and air tanks. That's about as fancy as I'd care to get, personally.

I mean at some point when you talk enough about "Cummins swap", "re-gear", "disc brakes", "lockers", "frame alterations", "axel swaps", "relocating this-and-that" etc, etc you really start talking about a different truck. And at that point you should have just purchased a different truck that comes with all those features.

I'm not sure that adding some slider bars or skid plates would violate DOT, though. Never really looked into it.

ymmv

 

[coachgeo]

I've thought about some sort of skid plate/protection for the fuel and air tanks. That's about as fancy as I'd care to get, personally.

I mean at some point when you talk enough about "Cummins swap", "re-gear", "disc brakes", "lockers", "frame alterations", "axel swaps", "relocating this-and-that" etc, etc you really start talking about a different truck. And at that point you should have just purchased a different truck that comes with all those features.

I'm not sure that adding some slider bars or skid plates would violate DOT, though. Never really looked into it.

ymmv

move the spare tire and put the tanks where they are on some of the commercial Brazos versions of the FMTV. Think a few military MTV variants put them there too?