SouthernSS – Combo Spring and Air Bag Setup (1 Viewer)

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From what I understand, he has the standard rear springs that come with the kit.
THESE

Unless he has the upgraded springs which are rated for 250 or 400lbs according to their website.

LOAD-LEVELING SYSTEM (Rear) (For +250lbs of Added Weight)AK31-59-005-02-02Height Adjustable Rear Spring from 1.8" to 3.2" with 250lbs of added rear weight.+1.8-3.2 in$499.00
LOAD-LEVELING SYSTEM (Rear) (For +400lbs of Added Weight)AK31-59-005-03-02Height Adjustable Rear Spring from 2.0" to 3.5" with 400lbs of added rear weight.+2.0-3.5"

Which makes me think if it’s worth it for me upgrade to the 250 or 400lbs.

On a daily basis, I think I’d have around 100lbs or slightly less of weight in the back (basic tools and a low-pro jack) and maybe other few items, I doubt this would make an impact on the standard springs since I assume they’re good for stock weight to 250lbs- and if I have more than 250 and I’m getting some sort of sag, then that’s when it’s time for some air.

Make sense? You guys think MD springs are worthy?

Edit: Scratch that, I might just go with 250lbs or higher as I’ll be adding some more weight like sliders, roof rack, and I always have my 1up bike carrier.
After looking at that kit, it might be the way to go, can't beat that price for everything you get honestly. Wonder how long the back order will take though.
Great find, curious to see how you like it if you decide to go that route!
 
Great info here!

Alright, definitely not the 4135 as it’s too short and does not fill in from top to bottom completely, like seen above in post #30.
4108 seems to be a great fit for the original eibach rear springs and Im sure other similar springs as well.

Couple screenshots from another fella on YouTube that also used the 4108 kit and shows how well it fits the eibach springs.
HERE for the video (@6:34).

I’ll be getting my suspension at the end of the month and will also purchase the 4108 kit and try figure out a way to use the oem compressor. I’ll come back with some install photo's and feedback!

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Thoughts on these after the install? I did the spring conversion with a lift, which is carefree. However, I would like to have a firmer rear spring and be able to "level" heavy rear weight when I need to. This seems like the best solution.
 
Thoughts on these after the install? I did the spring conversion with a lift, which is carefree. However, I would like to have a firmer rear spring and be able to "level" heavy rear weight when I need to. This seems like the best solution.

I actually haven’t installed the airbags just yet, but I did install the eibach stage 2 kit which is great so far. Great on streets and highways, especially with taking bumps and potholes. I had the pro lift kit, but on a 3rd gen taco and I know it’s 2 different chassis, but the front end definitely absorbs everything much much better.

I opted for the medium duty 250-400lbs, and at first it was it was pretty bumpy, bouncy, and springy but as soon as I put my normal stuff in the trunk and my 5th wheel on 285’s in (just to see how much of a difference it’ll be) and it’s much smoother. So I figure once I put my tire carrier and other items it’ll be pretty damn great!

Waiting on SPC UCA’s to come in so once I get that, I’ll install both the airbags and the UCA’s.
Front end feels a bit off when one side is extended and then compresses down again and I believe its due to the stock UCA’s. we’ll see.

Edit-
The photo attached is with 4 stock wheels and the one FJ wheel with 285/70/17 K02, so a good amount of weight in the trunk and it was sooo smooth and held up well with no droop or sag.

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Can anyone with the 4108 bags post a shot of the bags with pressure in them at ride height? And what's the ride height?

I'm curious if they are folded over on themselves at all inside the spring, or of they fill the shape of the spring nicely.

The 4135 bags expand to fill my springs reasonably well but again, my rear suspension is only about 1" over stock.
 
Can anyone with the 4108 bags post a shot of the bags with pressure in them at ride height? And what's the ride height?

I'm curious if they are folded over on themselves at all inside the spring, or of they fill the shape of the spring nicely.

The 4135 bags expand to fill my springs reasonably well but again, my rear suspension is only about 1" over stock.

I might install mine this weekend and I’ll post up pictures and measurements with and without air.

I’ll have to see how creative I can get with the air fittings since I'm not gonna be using the factory air compressor.

For the people that used the firstone fittings (or anything else) where did you guys put the fittings?
 
I might install mine this weekend and I’ll post up pictures and measurements with and without air.

I’ll have to see how creative I can get with the air fittings since I'm not gonna be using the factory air compressor.

For the people that used the firstone fittings (or anything else) where did you guys put the fittings?

I ran mine up through the top spring perch, back along the frame rails, and to a bracket I mounted alongside my trailer wire plug.
 
I might install mine this weekend and I’ll post up pictures and measurements with and without air.

I’ll have to see how creative I can get with the air fittings since I'm not gonna be using the factory air compressor.

For the people that used the firstone fittings (or anything else) where did you guys put the fittings?

Found a pic!

The bracket is made from one of the old levelling sensor brackets. 😁

I should probably make a thread one of these days for all the crap I did...


PXL_20210709_164843389.jpg
 
By the way, this is not my setup. I'm just documenting in a separate thread @SouthernSS – Combo Spring and Air Bag Setup

My goal is to keep questions and additional information on this combo setup on its own thread, so I can learn more.

Parts:
  • AirLift 1000 Air Bags for 4Runner
  • MetalTech Spring Conversion Kit
  • Radflo 2” Lift, Rear Springs and Rear Shocks
  • Re-use Lexus OEM Compressor
  • Re-use Lexus OEM air lines
Notes:

  • Installed air bags with nipple facing up (instead of downwards)
  • Connected the OEM air lines into the AirLift lines (had to remove some OEM clips)
  • Don’t cut the isolators as much as AirLift recommends

Seems like other rear springs from FJ Cruiser or 4Runner would work too. It would be great to document others who have done this combo setup with different parts.

Here's the original post: GX470 Suspension suggestions and overall height question

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Wish I would have seen this, I trashed all mine
 
Found a pic!

The bracket is made from one of the old levelling sensor brackets. 😁

I should probably make a thread one of these days for all the crap I did...


View attachment 2907191

Ahh! I like it! I definitely want it hidden. I’ve seen others place them on the hitch, which doesn’t seem like a very good idea…
I like how the 4th gen T4R’s guys do it and place them below the trunk door/in-between the trunk door and bumper.

Let’s see what I do.

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Well…but then it also doesn’t seem like a good idea. lol
I just imagined myself or someone else loading/unloading stuff and damaging them.
 
Ahh! I like it! I definitely want it hidden. I’ve seen others place them on the hitch, which doesn’t seem like a very good idea…
I like how the 4th gen T4R’s guys do it and place them below the trunk door/in-between the trunk door and bumper.

Let’s see what I do.

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Well…but then it also doesn’t seem like a good idea. lol
I just imagined myself or someone else loading/unloading stuff and damaging them.

I'll have to get another pic, these are tucked up nicely behind the bumper but just accessible enough to air them up by feel.

I like being able to check the bag pressure when I check tire pressure so needing to open/close the hatch might get old. I'm also not sure if there's even room with the GX style hatch. That does look really nice though on that 4R.
 
Can anyone with the 4108 bags post a shot of the bags with pressure in them at ride height? And what's the ride height?

I'm curious if they are folded over on themselves at all inside the spring, or of they fill the shape of the spring nicely.

The 4135 bags expand to fill my springs reasonably well but again, my rear suspension is only about 1" over stock.

20220404_095603.jpg
 
Here is the spot I put my air . I liked the 4runner idea but don't want to have to open back door. Weather ,tight spot etc.
This works because I'm here anyway if I'm towing

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Is anyone using the factory onboard air pump with a simple switch and/or pressure gauge? I would like to keep it as simple as possible.

I have a 2" lift in the rear. When I go offroading with buddies and gear, I would like to be able to pump up the rear a little to clear rutted out spots and hazards. Also, when I have a hell of a lot of heavy stuff in the back or a trailer, it would be nice to bring it up to "normal" ride height ........ and also not blind everyone with my headlights.

Are the 4108 bags tall enough for mildly lifted trucks?
 
Is anyone using the factory onboard air pump with a simple switch and/or pressure gauge? I would like to keep it as simple as possible.

I have a 2" lift in the rear. When I go offroading with buddies and gear, I would like to be able to pump up the rear a little to clear rutted out spots and hazards. Also, when I have a hell of a lot of heavy stuff in the back or a trailer, it would be nice to bring it up to "normal" ride height ........ and also not blind everyone with my headlights.

Are the 4108 bags tall enough for mildly lifted trucks?

I have about 2" to 2.5" lift in the rear and the 10"x4.75" bags fit perfectly. I also am using the stock pump with the sensors adjusted to keep pressure in the bags. I'm sure you could bypass the automatic sensors and just use the existing hi/low switch to adjust them manually. If you figure out how to do this please share, that would be excellent info!
 
It looks like a guy on Youtube shows his install



go to 6:20 because their first part is just about installing a hitch


Nice find! I didn't use super glue and its been fine for 70k but in hindsight I think it's a good way to go...time to find the super glue lol!
 
I finally installed the airbags. Pretty straight forward even with springs already on the vehicle. As long as the springs are unloaded you will be able to squeeze and finesse them in.

I actually do not like how the hose is off to the side. Looks like there can be a kink in the line once loaded and especially driving and going through dips, humps, or anything that makes the car bounce. If the hoses are GOOD hoses and can take a flex then it might be ok, but I suspect they won’t last long. Time will tell!

Just curious, has anyone had issues with the hoses? Seems like everyone has done it the same way so if no one has then I should be fine.

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I’ll try and get a shot of the hose “kink” later and see how it’s doing.

Don’t mind them worn out bump stops 😂
 
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I drilled a hole through the top spring mount/puck and ran it straight down. I’m not exactly sure how you ran yours. If you don’t do this that line will definitely get pinched or break. There a hole in the frame where the puck mounts to, next to the bolt hole. The line feeds straight down to the air bag.
There video somewhere with same set up (Eibach/Firestone) on this forum.
 
If you search this on YouTube you’ll find it. Sorry, don’t know how to copy link! GX470 Firestone Helper Bags using Factory Air System
 

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