Drivers Rear Sag-where to start

[Shes Mad]

I’ve worked on LC for years, but nothing newer.

So my daughter brings her GX470 with 200k over with rear sag and sway problems. Sway was easy-broken sway bar.

But I do not know anything about AHC or how it works.

The high normal low positions seem to work fine, but after a day or so, the drivers side rear sags way down, so something is leaking.

Just looking for what would be the most likely cause.

Thanks for the help!

 

[binaryaudax]

The airbag on the driver's side rear is probably leaking. You can either replace the airbag (there are some aftermarket options) or ditch the airbags and convert them to traditional coil springs.

 

[Shes Mad]

The airbag on the driver's side rear is probably leaking. You can either replace the airbag (there are some aftermarket options) or ditch the airbags and convert them to traditional coil springs.

Thank you. I’ll start there.

 

[Shes Mad]

I ordered new bags and sway bar and links. If this doesn’t fix it then it’s probably a line or connection somewhere which I’ll have to figure out

 

[Shes Mad]

I replaced the bags, which were pretty crusty. Original bags with 200k.

The drivers side still leaks down after a day. When I start the truck, It doesn’t automatically pump back up.
It is normally run in Normal. When I switch to High, then right back to Normal, its pumps back up to correct ride height.

I just want it at normal height and not leak down. I can’t find any leaks in the line from the bag to the accumulator.

Any thoughts? Can the accumulator leak just one side?

Anybody bypass the system and just put schrader valves and manually fill like a normal helper spring? Looks like the lines are 3/16, same as standard air brake lines. I can’t seem to find a 3/16 push in schrader valve though, so some adapting would be needed.

 

[Shes Mad]

Well I found the leak after spraying much soapy water on everything and just waiting. Tiny bubbles appeared on the backside of the Tee where the airlines connect to the accumulator. It’s in a plastic connector.

now I have to decide what to do next. It may be going to manual airline fills

 

[binaryaudax]

Should consider just ditching the airbags entirely and swapping over to coil springs instead.

Metaltech sells a complete kit: Metal Tech GX470 Rear Coil Conversion Stage 3 (Stock Height) - https://www.metaltech4x4.com/metal-tech-gx470-rear-coil-conversion-stage-3-stock-height/

Or you can piece it together yourself for cheaper (Moog springs, hockey puck and Energy Suspension bushings for the lower locator, junkyard for the isolators)

 

[Shes Mad]

Should consider just ditching the airbags entirely and swapping over to coil springs instead.

Metaltech sells a complete kit: Metal Tech GX470 Rear Coil Conversion Stage 3 (Stock Height) - https://www.metaltech4x4.com/metal-tech-gx470-rear-coil-conversion-stage-3-stock-height/

Or you can piece it together yourself for cheaper (Moog springs, hockey puck and Energy Suspension bushings for the lower locator, junkyard for the isolators)

That will probably be where I need to go. I see strutmasters also has a kit with shocks, but not much for keeping the springs in place like the Metaltech

 

[binaryaudax]

That will probably be where I need to go. I see strutmasters also has a kit with shocks, but not much for keeping the springs in place like the Metaltech

The shocks do not need to be replaced at the same time as the springs. The OEM electronically-adjustable shocks are a separate system from the ride height control.

If you're wanting to replace the shocks just because of age, look at the Bilstein 4600 series. You can get a set of all four on Amazon for ~$300. You'll lose the Comfort/Normal/Sport control on the center console, but you can replace that switch with a blank or a pocket (Toyota part number 58839-60040, about $23 on Amazon).

 

[Shes Mad]

Ordered Metaltech springs today.
thanks for the link

 

[Shes Mad]

Change of plans again. She wants a lift!

So now I'm doing more research

 

[Shes Mad]

I ended up putting in an Eibach stage one lift . Set the front shocks one slot from the bottom which should be 2.8 inch front and in the back should’ve been 3. The goal was just to get level. I actually gained 2 1/2 inches in the back and I didn’t have a pre-measure on the front but it looks pretty good. The rake looks a little different because it’s facing opposite directions on my driveway which has a slope to it. First picture is going up the driveway second picture is going down the driveway

 

[Shes Mad]

So now it really needs rims and tires. My daughter just bought these New Toyota four Runner Limited rims a couple years ago and new Michelin tires about a month ago.. They look really good on the GX but not so much with the lift. Somebody’s looking for a nice set of rims for the GX and brand new Michelin tires, here they are. This needs bigger tires now!

Michelin Defender LTX 265 60 18