Extended airbags vs rear coils (1 Viewer)

[grassfed]

Howdy all, 2006 268K

I’ve installed the front eibach stage 2s and tricked the rears with washers to get a little more lift in the rear.

In short, the ride doesn’t feel very balanced. I have searched and seen a member or two reference this problem. The rear is pretty stiff compared to the front. The auto level function is nice to have as an option moving forward though I rarely put heavy loads in and or pull with the GX.

For those of you that have gone to the extended airbags in the rear (airbag man etc) how has the ride compared to stock (non tricked) airbags? I’m debating either putting the eibach coils in the back which I by judging off of the fronts will ride very well and likely be more of a balanced feeling front to back. The coils will be cheaper, but will undoubtedly sag once road-trip camping stuff is loaded in.

I guess in short how is the ride quality of these extended airbags compared to tricked airbags for those of you that have gone that route?

Thanks in advance gurus

 

[Rednexus]

I have not tried extended airbags myself, and went straight from airbags to coils when lifting. I've never looked back. My GX gets loaded up with gear all the time and pulls a camper too. If you get adjustable coil rear lower perches, like the Ironman kit, you can fine-tune your ride height to account for that. I have mine set to 1" of rake unloaded and it drops to 0-0.5" of rake when the back is totally loaded up (for the camper we used a WDH and also set the rig to be close to level). I've never really missed the bags and it rides excellent with coils.

 

[rommelrommel]

I made spacers for the stock air bags, and it rides just like it did at stock height.

Extended air bags also solve the problem of the bags being at too high of a PSI and being too stiff.

 

[Jetboy]

I ran GX airbags on my 5th gen 4runner for a while. One consideration with spacers is that there's no internal bumper in the GX bags. So if you do bottom out, it's a very harsh bottom out of metal on metal. Not good. Extend the bumps to match if you're going to play hard.

There isn't going to be much difference between the bags extended a bit and longer airbags. With convoluted bags it's not much pressure difference to change height with the same load. It's mostly just adjusting the volume of air not the pressure. The poor ride is probably from the kdss more than the springs.

Good luck

 

[captainva]

I ran GX airbags on my 5th gen 4runner for a while. One consideration with spacers is that there's no internal bumper in the GX bags. So if you do bottom out, it's a very harsh bottom out of metal on metal. Not good. Extend the bumps to match if you're going to play hard.

There isn't going to be much difference between the bags extended a bit and longer airbags. With convoluted bags it's not much pressure difference to change height with the same load. It's mostly just adjusting the volume of air not the pressure. The poor ride is probably from the kdss more than the springs.

Good luck

The GX has different bump stops that are longer compared to the 4runner on springs. There is no metal on metal but bottoming out is less comfortable.

 

[Jetboy]

The GX has different bump stops that are longer compared to the 4runner on springs. There is no metal on metal but bottoming out is less comfortable.

Yeah - the GX bumps are longer and softer. They're a somewhat common mod for lifted 4Runners to swap over because most extended travel shocks will bottom out before you stop on the OEM bumps as well. The problem is if you add a spacer to the OEM airbag - you'll potentially bottom out the air spring before the OEM bump stop. That's why I was suggesting a comparable spacer for the bumps if you put a spacer under the air spring.

It's interesting that Toyota never sold a 5th gen 4Runner with air springs. All the brackets are on the frame and they share the same coil bucket with the mounting locations for the air springs as though it was originally planned to add them at some point. It makes converting super easy for a 4Runner to air springs.

The reason I ultimately removed them was because I couldn't find the right shock valving to work well with them. The air springs are highly progressive and almost all shocks are valved to match better with linear rate coils. I had fox suspension that I could adjust the valving, but I never had enough time to spend to go to a desert and spend a long weekend re-valving via trial and error to try to match up the two components. The result with the fox factory valving (that is also pretty highly progressive) was a soft highway ride that was also pretty uncomfortable in a car sick feeling sort of way. I think the frequency of the system was off. If it's too fast or slow it tends to lead to motion sickness. I wouldn't do it again without externally adjustable shocks that I could dial in easily to get a nice ride. Either OME BP51 or Bilstein 8100s or something similar. Matching with Fox rear shocks was not a good combo.

Slow speed trail performance was very good though. And I loved the ability to adjust height from sitting on the bumps to full shock top out at the push of a button (I had a custom manifold and compressor pump setup). Especially things like towing a trailer it was nice to never use the tongue jack. I really like air suspension when it's properly setup. I just never sorted it out well enough.

I had daydreamed for a long time about air/coil combo up front as well. I called every air spring manufacturer I could fine online and none of them could build a bag-over assembly to fit over a 2.5" shock body. Half of them thought I was just mis-measuring the outside diameter of the shock body because "no shock are that big". Lol. They're all fit for low rider tuner cars. But that would be my ultimate setup to have adjustable height front and rear so I could keep the great stock height highway manners and then jump up 3 or 4 inches for the trail when I needed it.

 

[HomersCanyonero]

Yeah - the GX bumps are longer and softer. They're a somewhat common mod for lifted 4Runners to swap over because most extended travel shocks will bottom out before you stop on the OEM bumps as well. The problem is if you add a spacer to the OEM airbag - you'll potentially bottom out the air spring before the OEM bump stop. That's why I was suggesting a comparable spacer for the bumps if you put a spacer under the air spring.

It's interesting that Toyota never sold a 5th gen 4Runner with air springs. All the brackets are on the frame and they share the same coil bucket with the mounting locations for the air springs as though it was originally planned to add them at some point. It makes converting super easy for a 4Runner to air springs.

The reason I ultimately removed them was because I couldn't find the right shock valving to work well with them. The air springs are highly progressive and almost all shocks are valved to match better with linear rate coils. I had fox suspension that I could adjust the valving, but I never had enough time to spend to go to a desert and spend a long weekend re-valving via trial and error to try to match up the two components. The result with the fox factory valving (that is also pretty highly progressive) was a soft highway ride that was also pretty uncomfortable in a car sick feeling sort of way. I think the frequency of the system was off. If it's too fast or slow it tends to lead to motion sickness. I wouldn't do it again without externally adjustable shocks that I could dial in easily to get a nice ride. Either OME BP51 or Bilstein 8100s or something similar. Matching with Fox rear shocks was not a good combo.

Slow speed trail performance was very good though. And I loved the ability to adjust height from sitting on the bumps to full shock top out at the push of a button (I had a custom manifold and compressor pump setup). Especially things like towing a trailer it was nice to never use the tongue jack. I really like air suspension when it's properly setup. I just never sorted it out well enough.

I had daydreamed for a long time about air/coil combo up front as well. I called every air spring manufacturer I could fine online and none of them could build a bag-over assembly to fit over a 2.5" shock body. Half of them thought I was just mis-measuring the outside diameter of the shock body because "no shock are that big". Lol. They're all fit for low rider tuner cars. But that would be my ultimate setup to have adjustable height front and rear so I could keep the great stock height highway manners and then jump up 3 or 4 inches for the trail when I needed it.

Interesting post. I had a similar experience not being able to match the valving of shocks to the valving of the rear airbags. Never thought of it in this context…but Bilstein 6112s in the front and stock factory rear shocks in the rear with tricked airbags…ride felt harsh and too firm in the rear.

I switched to basic OME rear shocks and the ride got worse. Bobble head effect in the front. Super bouncy upfront on some streets and some highways

I eventually converted the rear airbags to dobinson 675V coils with icon 56550 rear shocks to match the digressive front Bilsteins and the ride did get better for me.

I do miss the ability to adjust the rear height with the press of a button.

And interestingly enough…Scott Brady from Expedition Portal built up a GX470 for overlanding and he went with new rear airbags with a spacer, BP51 shocks all around, and timbren rear bumpstops. He has a YouTube video on his build.

But your point on using progressive shocks to match the air bags might be spot on. I just never got around to trying progressive shocks all around with the airbags

 

[grassfed]

Definitely a lot to consider. I got a little turned around when you stated that the volume of air is increased but the pressure is not changed that much with convoluted airbags. The idea is that the extended airbags don’t need more psi to get the same amount of lift. Same idea as stiffer springs (oem tricked) vs longer springs (airbagman extended airbags).

In any case with the progressive vs digressive vs linear I’ll likely not be able to achieve the desired result without going to coils. The ability to load it down and or pull something and not sag is definite win though.

Which spacer would be the best to use for this application? The idea of the bottom of the airbag sitting higher up off of its perch definitely gives the impression of instability and possibility of it slipping off of the perch when extended.

Thanks for the time everyone. It has been fun figuring out the different ways to go about this.

 

[Tywrap]

I have not tried extended airbags myself, and went straight from airbags to coils when lifting. I've never looked back. My GX gets loaded up with gear all the time and pulls a camper too. If you get adjustable coil rear lower perches, like the Ironman kit, you can fine-tune your ride height to account for that. I have mine set to 1" of rake unloaded and it drops to 0-0.5" of rake when the back is totally loaded up (for the camper we used a WDH and also set the rig to be close to level). I've never really missed the bags and it rides excellent with coils.

This. I did the ironman kit. Less worry about something failing in the airbag pump as well.

 

[grassfed]

This. I did the ironman kit. Less worry about something failing in the airbag pump as well.

Seems like the more bomb proof solution. Less fancy as far as “always” getting the correct ride height when loaded down, but I won’t be failed on the side of the road riding on bump stops because the system malfunctioned. Like I said I’m not loaded down very often so I should be honest with myself and do the practical solution.

 

[kerner]

I did Dobinsons IMS all around with springs set for 1.5" of lift in the front and tricked Arnott airbags while waiting on a set of extended bags from Airbagman. The spacers in the back have the rear with about 1/2" of rake and it rides great, with towing a teardrop I really love the adjustable/leveling air suspension. My experience with ride quality with spacers is that the Arnott bags were better than the stock bags (although mine were original), the Airbagman extended bags are better still. The difference between the extended bags and the new bags wasn't as extreme as replacing the original factory airbags, but it did make a difference.

The ride is great on and off-road with IMS and extended bags.

 

[kody472]

I did Dobinsons IMS all around with springs set for 1.5" of lift in the front and tricked Arnott airbags while waiting on a set of extended bags from Airbagman. The spacers in the back have the rear with about 1/2" of rake and it rides great, with towing a teardrop I really love the adjustable/leveling air suspension. My experience with ride quality with spacers is that the Arnott bags were better than the stock bags (although mine were original), the Airbagman extended bags are better still. The difference between the extended bags and the new bags wasn't as extreme as replacing the original factory airbags, but it did make a difference.

The ride is great on and off-road with IMS and extended bags.

Do you have a link to the Airbagman bags you purchased? I’m in the same boat with tricked bags, but would like to get taller bags. I tow with mine also and that feature is really nice.

 

[grassfed]

Do you have a link to the Airbagman bags you purchased? I’m in the same boat with tricked bags, but would like to get taller bags. I tow with mine also and that feature is really nice.

Last time I checked you have to inquire through their website and get a quote. What are you using for spacers in the rear? I had to get aftermarket bags but I went with cheapies at the time knowing that I would be going a different route at some point.

 

[centerisl]

And interestingly enough…Scott Brady from Expedition Portal built up a GX470 for overlanding and he went with new rear airbags with a spacer, BP51 shocks all around, and timbren rear bumpstops. He has a YouTube video on his build.

I am having Mule Expedition Outfitters do the exact same conversion (BP51, spacers, Timbren jouncers, new OEM air bags) - so I'll be able to report back on a before / after in about a month. I'm not looking for huge off-road gains but after 230k miles one of my (original) shocks is leaking and I expect the air bags to fail at some point. I am not - yet - replacing the steering rack as Scott did but I could see doing that at some point as well.

 

[kody472]

Last time I checked you have to inquire through their website and get a quote. What are you using for spacers in the rear? I had to get aftermarket bags but I went with cheapies at the time knowing that I would be going a different route at some point.

I'll check it out .

I replaced the factory bags with Arnott and right now I have washers under the height sensors giving me about 2" of lift.

 

[kody472]

I am having Mule Expedition Outfitters do the exact same conversion (BP51, spacers, Timbren jouncers, new OEM air bags) - so I'll be able to report back on a before / after in about a month. I'm not looking for huge off-road gains but after 230k miles one of my (original) shocks is leaking and I expect the air bags to fail at some point. I am not - yet - replacing the steering rack as Scott did but I could see doing that at some point as well.

I'm curious about the spacers they will be using. I'd love to buy a set if someone made them.

 

[centerisl]

I'm curious about the spacers they will be using. I'd love to buy a set if someone made them.

Air Lift 52420 (20 is the 2") - $75 on Amazon. They had me source the spacers and airbags, they are sourcing the OME and Timbren.

 

[Couve Cruiser]

I recently posted this on another airbag thread. Thought I'd repost here since the other thread hadn't seen recent activity.

I fabricated some rear airbag spacers fairly easily from some high strength ABS 2"x 4"x 12" bar stock. The minimum bar length was 12" from Mcmaster-Carr. I used a 4x4x2 piece and left it square to provide a more solid base for the spring to seat on. I drilled a circular channel using a 3 7/8 then a 3 3/4 hole saw on a drill press. I went about 5/16" deep. I beveled the inside corner of the channel to accommodate the weld bead on the inside of the air spring base. In the center i used a 7/8' spade drill bit to make a hole for the locating nipple in the center of the air spring base. I drilled the 7/8 hole deep enough to accommodate the nipple with room for a bolt head below it to bolt to the axle pad. On the bottom of the spacer i used a 75mm forstner drill bit to create a circular indentation to seat on the circular raised portion of the axle mounting pad. I used a dremel to bevel the outside edge of the indentation, to match the angle of the slope that descends from the flat center portion of the mounting pad. I'll include some pics to clarify things a bit.