My LS460 (2008) rear air suspension is not working properly. I have replaced both rear struts and the ride sensors but the LHS is riding low - about 1” lower than the other side - and there is a loud knocking sound when I hit a bump or pothole. The knocking is coming from the rear LHS only. I’ve adjusted the ride sensor without any success. Not sure what to do next? Any suggestions would be appreciated. Many thanks.

 

I would guess is that the left strut is faulty.

 

Yes, the left strut could be the problem.

Are they new oem struts or aftermarket, is the LR strut 1" lower than the front struts or just the RR, does the LR strut raise when in height high, did you have any problems with the installation of the struts or height sensors and are the sensors new or used?

 

Thanks Gerf and Angfanger,

The struts are brand new but not OEM. The side that was knocking before I changed the struts is the side that’s knocking now so I suspect it’s not the new LR strut that’s faulty. It’s just the rear left that’s riding low - it appeared to improve slightly when I selected ’High’ on the height adjustment but I will check if the height adjustment lifts the LR fender. It feels like air is not getting to the strut so maybe it’s a faulty pneumatic line?

 

I think if it was an air supply problem then the LR sensor would never hit its target and the compressor might not stop running just like if there was a leak. I would try going to both extremes on the ride sensor and confirming there was a good range of motion up and down to decide whether its the shock or just the adjustment and go from there. You can make a scribe mark on the rear adjustment if you want, there are some existing ones there from factory.

 

Thanks Gerf - I will move the ride arm to the maximum position and see if that helps. Do you know if I would hear the air pump running (without lifting the bonnet) - if it is leaking? Would there be an indicator on the driver console?

 

I don't think 1-inch difference would cause the strut knocking. I would be looking at control arms if the strut is actually working.

 

I can't hear my compressor running when I change heights even when I stand by the front passenger wheel well, I've read it gets louder when the mounting bushings go bad. There haven't been any success stories with swapping to aftermarket air shocks that I've read of even if it's only the fact that you lose the avs function.

I like them a little lower to avoid the hovercraft look

 

Hello Gerf - I’ve read further on the subject and it appears the new ride sensors need an electronic handshake with the air pump before they can be activated. I need to find someone with the Lexus software who can get the new parts talking to the car’s computer.

 

If your car moves up and down in response to the height high switch then the handshake has happened and the only thing left to do is set the ride height manually. I’ve never seen any calibration for the sensors and I have spent some time in that area of techstream.
It seems like you’re on the right track and I hope you get it figured out soon.

 

Recommendation is is replace the air suspension with Strutmaster Ride Glide and take the air suspension out of the equation.