How does one upgrade on the stock air suspension?

[ryanjl]

LR4 runs about 145 psi in the front air struts and 116 psi in the rear at "normal" ride height. I have a under hood compressor that's rated at 150psi, so normal height is attainable. You can also get into to tricks to make the compressor's job easier, such a as jacking a corner off the ground to get the corner you are working with at full extension. Alternatively, someone in your party could carry something like a Powertank. Those things are very handy for several different tasks.

I think you might be thinking of the earlier LR3's, which I understand used to run at something like 248 psi.

Whoa. Why the massive difference in psi? Given the suspension in the 3 and 4 is pretty much identical, is it just the air tank that's holding a lot more pressure, or is there actually more pressure in the air springs?

 

[avslash]

Yeah, I forget which vehicle forum I’m entering when I click the email link. I’ve got a 3, the AMK programming shuts off the compressor at 255psi. Even at 175psi it’ll have a hard time lifting the truck. It doesn’t matter that the 4 front struts run at 145psi, it needs more than that to raise the vehicle. I can’t imagine the 3 and 4 differ significantly in the psi they run in the bags.

I don’t ask because I doubt, I’ve looked at that system and have wondered how you get enough pressure into the system.

It's all in the manual. In addition to the corner strut numbers above, the max pressure from the compressor is 243 and reservoir working pressure is 253. Not sure how they reconcile those two numbers....seems like the compressor would at least output the standard reservoir pressure..Maximum reservoir pressure is listed as 333. So basically, your valve block system regulates pressure to the individual struts at the pressure posted above. Obviously higher for offroad/extended and lower for access settings.

You can get the weight off the affected corner by jacking the truck to extend the suspension. That way your compressor isn't fighting the weight of the truck. This could be done sequentially around the truck as well.

Or, as I mentioned, you can use something like a Powertank. I guarantee that will get it back to whatever height you want. Those cylinders are charged to something like 800-1000 psi.

 

[avslash]

Whoa. Why the massive difference in psi? Given the suspension in the 3 and 4 is pretty much identical, is it just the air tank that's holding a lot more pressure, or is there actually more pressure in the air springs?

I have heard, anecdotally, that it was be to address a high failure rate on early LR3 compressors, but that could just be internet folklore.