Been experiencing the rear of the car dropping as low as it could get when parked and engine off. Once started and on the move, it does come back up to normal ride level. What would cause it to drop? Thanks for any help.

 

Keith- The short answer is, you have an air leak. The bigger issue is, it can be a number things. It can be a leak in one or both of your air springs. It can be a leak somewhere in your air tubing that feeds your air springs. Or, it can be your air suspension compressor leaking down once you switch the car off. Your compressor has check valves inside of it that can fail over time and can vent off the system pressure, causing the air springs to deflate. The way that you can troubleshoot the system is to elevate the car SAFELY. This means using ramps or jack stands, NOT just using a floor jack. But make sure that the wheels remain under load. Then take a squirt bottle with soapy water and shoot your air lines, air springs, compressor and all components that are related to your self-leveling system. When you find the leak, you'll see it. It will start producing bubbles like crazy. I find that those "Bubbles in a Bottle" that kids play with work great. You probably won't hear it. Those leaks are rarely strong enough to produce that much volume to hear them. Good luck with the chase.

 

Is there a replacement for the DTS like Monroe has for the 2003 and older STS?

 

Arnott is one of the best options for Cadillac suspension systems. They re-engineer the parts the way they should have been designed the first time around. I just installed a new air compressor on my XTS and it while it was painful to have to do it on a 2013, they made the job almost easy with their ultra detailed instructions. The compressor is SO quiet, I need to get out of the car to make sure it's running. Awesome stuff! Here is a link for their DTS stuff:
https://www.arnottindustries.com/pro...n?condition=19
Looks like they offer everything you need for the 2003 STS as well, including the compressor. Here's the link for that:
https://www.arnottindustries.com/pro.../sts-only/2003

That should cure that saggy rear end. At least on your Cadillac...

 

OK, that first link did something weird. Here's the correct link for the DTS stuff:
https://www.arnottindustries.com/amf...de-2006-238125