With all the threads about the known air suspension issues I am wondering what is normal (as designed)? What is the normal height one should see at each corner from wheel center to wheel arch immediately after the car is parked on a flat surface? After sitting for a period of time, should the car hold the same height or should some sinking be expected? If so, how much would be considered normal? How do these values change with temperature? I do have some sinking on my 08 XJ8L and would like to know when I need to do something about it. Thanks

 

Hi jagcrue1,

Your questions about the factory specification for ride height are answered in this post:

Air Suspension & ECATS Summary: Components & Operation


It is normal for the ride height to vary slightly with changes in ambient temperature, but if your car is sinking as it sits, you have a leak somewhere in the system. The most common leak points are the air hose fittings at the compressor, the tops of each air spring/damper unit, and at the valve block and reservoir in the trunk/boot; and the top seals in one or more air spring. You can test for leaks by applying a small amount of soapy water to the fittings and top seals, taking care to not wet the electrical connectors for the ECATS solenoid valves. Bubbles indicate a leak. Carefully wipe everything dry after your tests.

Leaks at the air hose fittings can usually be repaired unless someone has overtightened the fitting and damaged the threads in the compressor, air spring, valve body or reservoir. Thus far, no one has developed an easy do-it-yourself remedy for a leak at an air spring top seal, so that usually requires replacement of the entire unit, or just living with the leak (as I have done).

Cheers,

Don

 

Thanks for the response Don. I do believe I have a leak that I can't seem to find in one of the air springs. I have tried the soapy water to no avail. I may just switch both of them out. Has anyone had any experience with RMT (Rebuilt Master Tech)? They have a 10% off special this month and can get both for $550. I do like the air ride and would like to avoid the coil spring swap.