LMTV Cab Suspension Airbags Alternative

[Awesomeness]

That's not correct for the combo unit. Jeff was very patient about getting this clarified: PP997900 is for the bag only. It was ~$500 for a shipped pair. He had a separate number for the shock (PP954900) and it is definitely NOT included with the PP997900. The combo unit was something like $439 each, it was ~$900 with freight if I had pulled the trigger.

Ohio Hydraulic even list the two components together on the same page with their individual prices:

Search Results for: PP997900

I called Jeff, and the current price PP997900 air bag is $246/ea, 1-2 week lead time.

The part number for the whole "combo unit" is PAS259. 10+ week lead time.

 

[tennmogger]

There is a replacement air bag that works. I have one installed on a truck for a couple of weeks to verify ok. It may be for a Volvo and is very slightly different, hence the different part number. The part number is KA-5066. There's no "PP" number associated with it and that may explain why searches have not found it before.

Look on the epay place and search for KA-5066. One hit you will get is a cab suspension bag, complete assembly, with shock absorber. It looks exactly the same as the original LMTV assembly with the exception that the cross link that secures the upper end of the shock is about 90 degrees different. Makes no difference to our installation. The air feed hole, for the hardline input, is located correctly too.

I will make this disclaimer: I found the first KA-5066 from a mom-and-pop store and they had only the one. That's where the KA-5066 number came from. This is the one I have been running. Found another couple, all that source had, then this epay source showed up. I have not bought from this current epay source but they seem to have plenty.

I would post the direct link but I think there's a rule against that. Sorry.

 

[coachgeo]

well this looks interesting..... So interesting I just canceled my order for the ones just above and purchased below kit instead with thoughts that any future repairs needed will be significantly less costly. ...

2909A000 made by cabmate

BUTTT it is sold as being for a sleep cab so I do not know if it will be heavy duty enough. Suggest adding limit strap so if in an accident you for sure have extra security that this wont pull apart, ripping the cab off the chassis. Then again... hmm... might be better to let the cab come off and the heavy truck keep rolling away..... Maybe put an ejection system to just jettison the cab away from the big heavy truck that just wants to crush you lol

found this for about 400 bucks on both fleabay and an air suspension truck supplier

 

[coachgeo]

well this looks interesting..... So interesting I just canceled my order for the ones just above and purchased below kit instead with thoughts that any future repairs needed will be significantly less costly. ...

2909A000 made by cabmate

BUTTT it is sold as being for a sleep cab so I do not know if it will be heavy duty enough. Suggest adding limit strap so if in an accident you for sure have extra security that this wont pull apart, ripping the cab off the chassis. Then again... hmm... might be better to let the cab come off and the heavy truck keep rolling away..... Maybe put an ejection system to just jettison the cab away from the big heavy truck that just wants to crush you lol

found this for about 400 bucks on both fleabay and an air suspension truck supplier

an issue occurred to me... both OEM bag setup and maybe this one too ..... sticks out enough from chassis that larger tires (14's maybe... and 16's for sure) can rub them. hopeeeeefully it has a shorter bag since the shock is outboard. shorter bag should raise the widest point of the whole shebang (air bag base) up more giving more clearance for taller tire

 

[Third From Texas]

an issue occurred to me... both OEM bag setup and maybe this one too ..... sticks out enough from chassis that larger tires (14's maybe... and 16's for sure) can rub them. hopeeeeefully it has a shorter bag since the shock can be outboard. shorter bag should raise the widest point of the whole shebang up more giving more clearance for taller tire

I was looking to mod my A1R with a cab air system that would also have some adjustment (a stock cab vs a fully radio/turret cab vs an armored cab vs a luxury RV cab all have *very* different contents and weights). I had spoken to the fellow who put together the LMTV aftermarket kits (not the point_of_compass who simply copied the design and sell them, but the guys who did the initial design). I never followed up on it with him, though.

Not all cabs weigh the same, so an adjustment to accommodate for such would be a worthy addition. But after reports of the aftermarket kits rubbing in a number of circumstances I decided to stick with the A1R rigid design.

My theory is that with no air bags to break...one less system to fail.

 

[coachgeo]

''' number of circumstances I decided to stick with the A1R rigid design.

My theory is that with no air bags to break...one less system to fail.

for everyone else (A0, A1) the tires rub the OEM..... aftermarket uses same bag base on the chassis. How do the A1R mount? are they a coil over shock or is the hoop just on a solid pivot pin mounted to the chassis?

 

[Third From Texas]

for everyone else (A0, A1) the tires rub the OEM..... aftermarket uses same bag base on the chassis. How do the A1R mount? are they a coil over shock or is the hoop just on a solid pivot pin mounted to the chassis?

It's...different. I mean, there is no airbag to rub and the coilover is where the shock is (obviously).

 

[coachgeo]

It's...different. I mean, there is no airbag to rub and the coilover is where the shock is (obviously).



View attachment 848095

thanks..... knew there was coil over on the axle shock. Didnt know if they copied the Steyr where they have a coil over on the cab hoop where we have airbags for A0, A1. so how is the cab hoop that back of cab locks too attached to chassis with out sitting on airbag?

 

[chucky]

I was looking to mod my A1R with a cab air system that would also have some adjustment (a stock cab vs a fully radio/turret cab vs an armored cab vs a luxury RV cab all have *very* different contents and weights). I had spoken to the fellow who put together the LMTV aftermarket kits (not the point_of_compass who simply copied the design and sell them, but the guys who did the initial design). I never followed up on it with him, though.

Not all cabs weigh the same, so an adjustment to accommodate for such would be a worthy addition. But after reports of the aftermarket kits rubbing in a number of circumstances I decided to stick with the A1R rigid design.

My theory is that with no air bags to break...one less system to fail.

When i get around to it i will find the perfect coil spring to replace each air bag with a coil spring bing bam boom to never be looked at again !

 

[chucky]

It's...different. I mean, there is no airbag to rub and the coilover is where the shock is (obviously).



View attachment 848095

Does this coil over fit the AO fmtv the shock top towerl looks wider than the AO shock tower !

 

[Third From Texas]

How is the cab hoop that back of cab locks too attached to chassis with out sitting on airbag?

Heh, there is no floating hoop. The A0 system is deleted completely. There is a brace that is hard-mounted to the back of the cab and the cab latch meets that rigid brace. Too dark out now to get a proper pic.

Does this coil over fit the AO fmtv the shock top towerl looks wider than the AO shock tower !

I suspect that it's wider but my A0 truck isn't here at the moment to compare. But the coilover is like 6" diameter. Pretty sure that the mounting holes are all the same (the air ride system holes are still present in the frame, of course...)

 

[chucky]

Heh, there is no floating hoop. The A0 system is deleted completely. There is a brace that is hard-mounted to the back of the cab and the cab latch meets that rigid brace. Too dark out now to get a proper pic.

View attachment 848097



I suspect that it's wider but my A0 truck isn't here at the moment to compare. But the coilover is like 6" diameter. Pretty sure that the mounting holes are all the same (the air ride system holes are still present in the frame, of course...)

Misunderstanding im wondering will that coil over shock on the front axle picture fit as a shock absorber on a front axle for fmtv AO like a 1083 ?

 

[Third From Texas]

Misunderstanding im wondering will that coil over shock on the front axle picture fit as a shock absorber on a front axle for fmtv AO like a 1083 ?

No, I track. Can't say until I look at my A0, though. I know all the holes in the frame are identical but the shock tower may be different. I'm pretty certain that it is different as the coil over is 2x the diameter. But I could be the same....will a A0 tower hold a 6" diameter shock (vs the OEM 3")?

 

[Ronmar]

Yea, thats a different shock tower. And unless you add half a ton+ of armored cab mass for that extra spring to work with, I am going to guess that the ride will be a little harsh…

 

[chucky]

No, I track. Can't say until I look at my A0, though. I know all the holes in the frame are identical but the shock tower may be different. I'm pretty certain that it is different as the coil over is 2x the diameter. But I could be the same....will a A0 tower hold a 6" diameter shock (vs the OEM 3")?

Copy that ! That shock looks bad ass but Ronmar probably hit a bullseye on it was for the the armored cabs extra weight ! but that sise spring but not as heavy is what i want to replace the airbags with maybe a little smaller around than your pinky finger maybe!

 

[Third From Texas]

Copy that ! That shock looks bad ass but Ronmar probably hit a bullseye on it was for the the armored cabs extra weight ! but that sise spring but not as heavy is what i want to replace the airbags with maybe a little smaller around than your pinky finger maybe!

If you think it thru, the coil over really has no bearing in the discussion of cab air (and visa versa). The cab air was deleted because it would have exploded the bags under the added weight of the armor. The coil over was simply added to accommodate the extra weight of the armor. They are actually separate and unrelated (beyond that).

The coil over is NOT a cab air replacement. It's merely there to handle the added weight of the armor on the suspension. I could run A0 shocks and likely have a far smoother ride (since my cab has no armor).

If you want to do away with cab air, just delete the whole works and mount the latch in a rigid configuration. That's all they did for the A1R. The coil over is unrelated.

 

[Third From Texas]

Here's a better pic of the cab air delete on the A1R trucks.

The "floating hoop" is gone as are the bags and mounts. A brace is mounted to the back of the cab and the same cab latch mechanism is used.

The cab is rigid to the frame (the suspension seat upgrade provided any "kush ride" and they actually did as good a job as the air ride, IMO).

*You'll note that my cab latch has a set of bushings and they are pretty crusty...

 

[Third From Texas]

Now if you really wanted to have some engineering fun, ditch the cab latch bushings shown above and incorporate a single, centrally located air bag at the latch.

 

[Third From Texas]

delete me

 

[chucky]

If you think it thru, the coil over really has no bearing in the discussion of cab air (and visa versa). The cab air was deleted because it would have exploded the bags under the added weight of the armor. The coil over was simply added to accommodate the extra weight of the armor. They are actually separate and unrelated (beyond that).

The coil over is NOT a cab air replacement. It's merely there to handle the added weight of the armor on the suspension.

If you want to do away with cab air, just delete the whole works and mount the latch in a rigid configuration. The coil over is unrelated.

Put your helmet back on ! The reason the coil over shock was mentioned is 2 fold ! A. when i saw the picture 2 things came to mind that i wondered if that shock would fit on my AO truck and B. the circular sise of that coil spring looks close enough to use in place of a airbag but in a smaller gauge spring i want my cab to have some movement that a spring could do just fine instead of rideing around with the cab pinned and jarring your teeth out was my observation !