Replace my 2006 Forester self-leveling (sls) struts and springs with non sls strut and springs?

I have a 2006 Forester 2.5X L.L. BEAN with 95K miles and my struts were just replaced at Mavis. After, we drove it about 800 miles and then noticed it looked low in the back. When I asked about it they said my rear springs must need replacing.

It turns out that the mechanic didn’t know that the LL Bean Edition has self-leveling in the rear suspension (sls) and requires a different strut (and spring) than those found on a regular '06 Forester.

Should I do what the Mavis mechanic is recommending and replace my sls-springs with standard ones to match the standard strut that was installed in error? Or should I have them do what Subaru is recommending and put in proper, new self-leveling rear struts (and the springs that go with them). A standard kyb strut and a stiffer spring (an oem non-sls spring) is quite a bit cheaper than those sls struts. I would have just done sls if I had been asked in the first place.

As I understand it, SLS struts “pump up” to increase the pressure and stop the back end from sagging with a heavier load. They use a weaker spring and use the strut to control ride height. If you replace the SLS struts with conventional struts without changing the springs to a stiffer version, the car will ride several inches too low. This is what is happening to me.

If I follow their advice I will save money but will I also be risking other problems? (like distended struts? tire wear?). Is it advisable to just put in the oem sls struts and springs?

Any advice here is appreciated. I am leaning toward returning the car to stock. Subaru has confirmed that the '06 Forester LL Bean is a self-leveling suspension off the lot.

Edit: Forget what I said. Sounds like they pump themselves up and is a common problem because the replacements are about $500. If you replace the struts then have to replace the springs too.

Seems to me if it had the air struts in it you need to replace it with air struts. It would be virtually impossible for an installer not to know they were air struts since they have plastic air lines attached to them. What else did they do? Disconnect or disable the ride height sensor? Throw the air lines away? Better find out first how much damage they did before having them put the correct struts in.

Bing, I believe these are self-contained units. My feeling is also to go back to stock.

Thanks for your help guys! Quick update. I ended up taking my car to my local mechanic. In the hopes that this information might help someone else I have posted some nice details below:

Excel-G is not a self-leveling replacement part

We confirmed that the struts placed in my Subaru Forster 2006 LL Bean were Excel-G, Part Numbers 339149 (rear right) and 339150 (rear left) struts. The kyb catalog ( or reveals these are "(Exc. Self-Leveling Rear) Recommended OE Replacement." The "Exc." means OE replacement "Except" in the case of self-leveling. It's not a self-leveling replacement part.

Transition from SLS to non-SLS

After reading on I opted to transition to non-sls. One forum member (ForesterMatte) posted an awesome step-by-step with pix of his transition. One photo clearly shows the difference between sls and non-sls struts and springs. I ended up getting oem, non-sls rear springs from Subaru and a new set of Monroe OESpectrum (72445). For some reason the OEM spring with the kyb struts Mavis put in did not fix the issue of sag. The Monroe strut did. Perhaps my riding around on the kyb damaged it? (I wouldn't have thought so). The sagging is gone now. Having non-sls saves a bit of money but it was a very frustrating experience.

One detail I forgot to include. The step-by-step sls to non-sls post by ForesterMatte is here.