Is it possible to change the OEM air suspension for the 2001 ls430 UL to an aftermarket air suspension with little to no change?

 

*edit* - link is for coil springs

Yes. There's lots of into on here about it. Here's a good place to start:

https://www.clublexus.com/forums/ls-...onversion.html

 

I think he's asking about aftermarket air suspension, not aftermarket coil spring suspension. Converting to coilovers or coil spring suspension is straight forward, but I have never heard of anyone using aftermarket air suspension pieces along with the OEM air ride bits. I think there are, or were, aftermarket air shocks available for the LS430, but they are/were a direct OEM replacement, not the kind of the stuff you find with custom aftermarket air suspension kits that people use to retrofit air suspension to their car.

 

Whoops... My bad. Didn't see that second "air" in the sentence

 

My 04 Ls430UL , 115k is in the garage. We heard a loud noise from inside the house, went out to look and found the car with its rear end almost on the floor. I’m assuming an air bag probably ruptured. At first it was sagging on the right side - then I started the car and the left side sank as well.

I may want to convert to standard suspension. Referring to the post above, does someone know the correct rear spring to maintain ride height for the UL model given the extra weight in the rear?

thanks.

 

Unfortunately there is no specifically "correct" coil spring for the UL model since they all came with air springs. Any coil springs out there are designed for the base, ML and CL versions. If you're worried about the car sitting level, you might want to consider a set of coilovers since they're adjustable. You could set the ride height to whatever you want and probably get a more level appearance than stock air ride since the factory air ride tended to have the front sitting higher than the rear. Certain companies will customize the spring rate and damper valving for the coilovers they make so you don't have to end up with a harsh or sporty ride like most coilovers have. However, any suspension other than the factory air springs will be "less soft" than what you're used to. Just my 2 cents.

 

Thanks. I see some posts that suggest KYB shocks and OEM springs are the way to go and that many of the coil over kits are suboptimal.

any suggestions as to where to look for coilovers?

 

A set of acceptable coilovers starts at $1000 and goes up from there. There are many coilovers priced below that and they are generally garbage for ride quality and longevity, sold mostly to just lower a car to make it look cool while sacrificing virtually everything else. As you go over $1000 things usually get better. The only experience I have with coilovers on an LS430 are from BC Racing. They are good value for money at $1200 for the set, and probably the cheapest/lowest quality I'd put on a car. My friend had them on his first LS430 and they rode very nice. The company will also customize them with any spring rate you want and match the valving to the spring rate, so you can request a spring that is comparable to the stock spring rates. There are other companies that will do the same.

For coil springs, I've also heard that KYB struts and OEM springs are a good match, but I don't have any personal experience with them. You can also get OEM struts. However, there are two different part numbers for OEM springs and struts, and I don't know what the difference is. Maybe someone else here knows? For example, 4813150120 and 4813150130 are both listed for front springs for an 01-03 car. Both can be used on the left or right. The same goes for rear springs, front struts, and rear struts. Each have two different part numbers with slightly different prices.