Rear Suspension Airbag install questions? (3 Viewers)

[2021 LC200]

Bought Rear Suspension Airbags from Australia (Airbag Man - CR5051HP) for my 2021 LC200 purchased in the US.

Have two questions:
1) Without installing an onboard build in air compressor, what is a good location at the rear of the vehicle for the two inflation valves allowing manual inflation, i.e. using a 12v handheld air compressor? My LC200 is stock base model, so standard rear bumper etc.
2) Following the LC200 project website by Jamie Benaud (Project 200 - Toyota LandCruiser 200 touring build) and video on the air bags installation

I am getting ready to install myself (excluding the onboard compressor and ability to control from the driver seat...). When he gets ready to lower the axle 1) he removes the rear sway bar connected to the KDSS actuator, 2 ) the shocks, 3) the diff vent hose and 4) the brake line bracket. On my 2021 model, is there anything else i need to take care off before lowering the axle with the jack? I was thinking for example the headlight leveling mechanism.

Appreciate your insights. Also any pictures of your install of the two inflation valves would be great.

Thanks a lot and Happy Holidays!

 

[scottm]

Subscribed, I need to do this. I'll tow my boat twice a year, manual inflate will be plenty good. Looks a bit more challenging than it was on my 80.

 

[kcjaz]

I’ve not installed air bags but I did add spacers. It was not necessary to disconnect the sway bar for the drivers side but is to get the passenger side spring out. I disconnected the sway bar on the passenger side because I thought it would be easier and used a bottle jack to lower and raise the bar. I don’t think it really matters which side you do.

 

[FrazzledHunter]

Subscribed, I need to do this. I'll tow my boat twice a year, manual inflate will be plenty good. Looks a bit more challenging than it was on my 80.

We're in the same boat...pun intended although I don't have an 80 or a boat LOL. I'm working on getting ready for towing, however.
I'd love to hear about a good installer in the Baltimore Maryland area.

 

[scottm]

One thing I will do is have the lines open when not in use, with some filter breathers. On my 80 I figured out the air bags still had air in them to compress, even when no pressure was in them. There was no way I'd get full articulation unless I could let more air out as the spring and bag compressed.

 

[2021 LC200]

Searching this morning I found the following examples of inflation valve imstalls. One showing it beside the 7 pin is not the same setup as my stock LC 200 (7 pin is more under the vehicle and at a slight angle). In any case, will look today a bit at the rear of the vehicle to find a good place. I can see getting some aluminum angle material as a bracket to hold the valves.

Anybody who has done a nice install and is willing to share some pictures, please do!

 

[TeCKis300]

I've been debating this. I have bags left over from my 100-series that also fit the 200-series.

I don't particularly have a need for this as my rig tows great. AHC hasn't complained a bit with ride and damping on point. But then the scale has told me my rear axle is at 5000lbs when towing so I can't help to think it may be good augmentation or backup.

Airbags are cheap and easy to install anyhow with practically no impact when deflated.

 

[2021 LC200]

One thing I will do is have the lines open when not in use, with some filter breathers. On my 80 I figured out the air bags still had air in them to compress, even when no pressure was in them. There was no way I'd get full articulation unless I could let more air out as the spring and bag compressed.

I understand they recommend min 5psi to keep the bags and sleeves in place. I would expect articulation at 5psi and the bump stops cut off is going to be about the same or basically not seriously affected. Anybody with experience on an LC200, I am interested.

 

[Sandroad]

You can inflate the airbags easily with just a bicycle pump. No need for power or high tech. I mounted my valves in holes in the bumper created by removing a couple of clips. Bad idea......the valves face down and over time salt and mud and fine sand find their way past the seal and mess up the valve. Install them where they are protected at least a bit from road crap. The Firestone airbags I used need a few psi all the time to keep them in place and from moving around. Since the install requires removing most of the jounce rubber, I would be not be comfortable with deflated bags. I did one side at a time and was able to get the springs out without removing the sway bar but I did open the KDSS valves 3 turns.

 

[2021 LC200]

You can inflate the airbags easily with just a bicycle pump. No need for power or high tech. I mounted my valves in holes in the bumper created by removing a couple of clips. Bad idea......the valves face down and over time salt and mud and fine sand find their way past the seal and mess up the valve. Install them where they are protected at least a bit from road crap. The Firestone airbags I used need a few psi all the time to keep them in place and from moving around. Since the install requires removing most of the jounce rubber, I would be not be comfortable with deflated bags. I did one side at a time and was able to get the springs out without removing the sway bar but I did open the KDSS valves 3 turns.

Thanks a lot for the tips. The air bags I have are Firestone with in addition bags/sleeves to protect them. Re the debris, I may look at some kind of plastic junction box facing rear and/or some valve covers as used on tires to keep them debris free. Do you mind sharing a picture of your valve install?

 

[Cruiser17]

Not the best pictures but included because we all love pictures. I installed Firestone airbags while keeping stock rear springs. Rear shocks are icon 2.5 with remote resi. Fronts are the matching icon 2.5 coil overs without the remote resi.

It’s been 2+ years so I don’t recall exact install, however, I did use the OP Airbag Man video as a reference and remember it to be super easy install. I ran the lines to a tee and mounted the fill valve in rear bumper. I just keep a valve stem cap on it to keep dirt out. Additionally I use the Milwaukee m12 compact inflator when I tow to inflate and deflate. I tow a 25‘ airstream and quickly inflate to 25psi when towing and deflate to 5 psi when I unhitch. My cruiser pulls like a dream with this set up. 20,000 miles with absolutely zero issues. No issues with the bags tee’d for me.

 

[Sandroad]

Thanks a lot for the tips. The air bags I have are Firestone with in addition bags/sleeves to protect them. Re the debris, I may look at some kind of plastic junction box facing rear and/or some valve covers as used on tires to keep them debris free. Do you mind sharing a picture of your valve install?

Mine look exactly like that of @Cruiser17 above , except I have 2 because I did not "T" the line. I did buy valve stem caps with a neoprene seal inside to prevent the corrosion I mentioned earlier.

 

[scottm]

I understand they recommend min 5psi to keep the bags and sleeves in place. I would expect articulation at 5psi and the bump stops cut off is going to be about the same or basically not seriously affected. Anybody with experience on an LC200, I am interested.

I guess you are right, forgot about needing pressure to keep them in place.

I can't help think they will limit articulation though. If you keep 5psi above atmospheric pressure, about 20psi absolute. Compress then halfway, you have about 40psi absolute, about 25psi on a gauge. Cross-section of about 6" diameter is 28 square inches, 25psi X 28 = 700-lb of force to compress the bag half way. About 1,820-lb to compress the bag to 1/4 height. That is in addition to force required to compress the spring.

How much spring compression until the bump-stop limits travel? If it is half the spring length from at-rest compression, maybe 700-lb won't limit it a lot. If it is 1/4 spring length max-travel, that would take a lot more force to articulate fully. I never really noticed a big difference in my 80, but my offroading in Michigan was mostly construction sites with a construction trailer.

I'm also interested in hearing if anyone has checked their articulation before and after installing airbags? I still need to install them, just wondering.

Thanks for the links and pics.

 

[2021 LC200]

I guess you are right, forgot about needing pressure to keep them in place.

I can't help think they will limit articulation though. If you keep 5psi above atmospheric pressure, about 20psi absolute. Compress then halfway, you have about 40psi absolute, about 25psi on a gauge. Cross-section of about 6" diameter is 28 square inches, 25psi X 28 = 700-lb of force to compress the bag half way. About 1,820-lb to compress the bag to 1/4 height. That is in addition to force required to compress the spring.

I'm also interested in hearing if anyone has checked their articulation before and after installing airbags? I still need to install them, just wondering.

Thanks for the links and pics.

Remember now that the bump stops are almost entirely removed which creates quite a bit of space. In addition I understand the traction control system of the LC is so good that one wheel in the air at extreme articulation is a non issue. In any case, I am installing mine to tow a travel trailer also because I prefer not to use a weight distributing hitch (which mechanically makes me shiver when you consider what it does).

 

[scottm]

Remember now that the bump stops are almost entirely removed which creates quite a bit of space. In addition I understand the traction control system of the LC is so good that one wheel in the air at extreme articulation is a non issue. In any case, I am installing mine to tow a travel trailer also because I prefer not to use a weight distributing hitch (which mechanically makes me shiver when you consider what it does).

I agree, love how well airbags work, even for loading the vehicle heavy. I used to load up my grown kids and all their luggage on the roof, seven of us and a golden retriever, and drive four hours north. I couldn't believe how stable the 80 handled on the highway with the airbags aired up with that load.

 

[TeCKis300]

Remember now that the bump stops are almost entirely removed which creates quite a bit of space. In addition I understand the traction control system of the LC is so good that one wheel in the air at extreme articulation is a non issue. In any case, I am installing mine to tow a travel trailer also because I prefer not to use a weight distributing hitch (which mechanically makes me shiver when you consider what it does).

Depending on the size of the travel trailer, particularly if it's over 4-5k lbs, I would encourage you to reconsider the WD hitch. If I may offer my 2 cents..

Air bags can work great with heavier tongue weights, but are not a replacement for a WD hitch. They do completely different things. You can run safely without airbags as all they do is support the rear suspension with added spring rate. But it is arguable if one can run safety without a WD hitch particularly at higher loads and higher speeds, or in a dynamic situation. WD hitches restore front axle weight for better control and overall stability against sway, and is an important safety device particularly as our rigs have shorter wheelbase and relatively long rear overhangs.

 

[scottm]

Depending on the size of the travel trailer, particularly if it's over 4-5k lbs, I would encourage you to reconsider the WD hitch. If I may offer my 2 cents..

Air bags can work great with heavier tongue weights, but are not a replacement for a WD hitch. They do completely different things. You can run safely without airbags as all they do is support the rear suspension with added spring rate. But it is arguable if one can run safety without a WD hitch particularly at higher loads and higher speeds, or in a dynamic situation. WD hitches restore front axle weight for better control and overall stability against sway, and is an important safety device particularly as our rigs have shorter wheelbase and relatively long rear overhangs.

Is this hitch built to transmit the forces from a weight-distribution hitch to the frame? 80 and 100 hitches didn't have a lot of structure for those kind of forces.

 

[2021 LC200]

Depending on the size of the travel trailer, particularly if it's over 4-5k lbs, I would encourage you to reconsider the WD hitch. If I may offer my 2 cents..

Air bags can work great with heavier tongue weights, but are not a replacement for a WD hitch. They do completely different things. You can run safely without airbags as all they do is support the rear suspension with added spring rate. But it is arguable if one can run safety without a WD hitch particularly at higher loads and higher speeds, or in a dynamic situation. WD hitches restore front axle weight for better control and overall stability against sway, and is an important safety device particularly as our rigs have shorter wheelbase and relatively long rear overhangs.

Thanks for pointing this out. I believe I understand what a WD hitch does and the benefit in downward force on the front axle improving overall control. I just personally can not get around the idea to transfer through some push rod system enough torque to compensate for the 500 to 800 lbs or so hitch downward force. All that force (torque) is put on the hitch and the rear chassis beam, not even considering any dynamic loads as you drive over bumps at speed or go through corners. Well, my plan is not to use it and see how it goes. With a heavy truck like a LC200 I expect no issue with road handling and control. In the land down under they tow with LC200's big off road capable caravans with full articulating hitches (like the Black Series HQ19 and HQ21). Obviously after trying I may change my mind and get a WD hitch.

 

[TeCKis300]

Thanks for pointing this out. I believe I understand what a WD hitch does and the benefit in downward force on the front axle improving overall control. I just personally can not get around the idea to transfer through some push rod system enough torque to compensate for the 500 to 800 lbs or so hitch downward force. All that force (torque) is put on the hitch and the rear chassis beam, not even considering any dynamic loads as you drive over bumps at speed or go through corners. Well, my plan is not to use it and see how it goes. With a heavy truck like a LC200 I expect no issue with road handling and control. In the land down under they tow with LC200's big off road capable caravans with full articulating hitches (like the Black Series HQ19 and HQ21). Obviously after trying I may change my mind and get a WD hitch.

Rather than convince you as you do seem to understand this with good consideration... I'll add some insight that I've learned over the years, towing at the upper end with the 200-series with an ~8,300 lb trailer. It's wholly possible that performance is different at lighter weights.

- Agreed that WD forces at the hitch can be tremendous to transfer those kind of weights. Saving grace is that the structure is designed for it and the manual calls out the need to use a WD hitch with trailer weights above 5000lbs. Other variable is the amount of WD tension that is dialed in is under user control to ultimately dictate how much force is applied.
- Tweaking my WD hitch, the rig is okay with minimal tension. It's notably better and great with appropriate tension (~50% FALR, front axle load restoration). With too little tension, the rig can be squirrely with passing rigs, cross winds, particularly around mountain passes, etc. It becomes absolutely stable and resolute with proper setup, well into higher speeds, making towing long distances much more relaxed
- With heavier trailers, without WD, it's easy to exceed the 4300lb rear axle weight rating. Sharing that load between the axles may be worthwhile for longevity of the axle and tires
- AUS trailer designs are different and generally utilize longer draw bars/tongues. This minimizes tongue weight, increases tow vehicle influence on the trailer, and increases stability.

 

[Eric Sarjeant]

Skip to 4:53 in this video. This does exactly answer your question “manually”. But it does give an alternative way how we do this for customers.