Shaz430

Hi guys I've had my LS430 for about 9 months now and loving it, however in the last month I've had issues with the rear suspension. Couple of months ago my battery went totally flat and the rear went right down. Once battery was charged it returned to normal. However in the last month the rear has been sitting very low. The normal setting the arch is right at the tyre and rubs over speed bumps. I've currently got it set at high and is now sitting where the normal should. So the suspension is going up and down, just not to the positions it should be. Front sits exactly where it should, any ideas what could be the issue with the rear? It's a 99 model, thanks in advance.

Hi guys, thought I'd post a quick intro. Anyway I'm shaz from kilmarnock, Ayrshire. I've had Jap or rwd nearly all the time. Previously had a couple of mk3 supras and then an r33 gtst skyline but now due to family I've a lexus LS430 and I must say it's been impressive as I was always scared anything after the skyline and supras would feel sluggish. But the lexus not only has the power and the comfort and reasonable on fuel, well as much as a v8 can be. Car has been a dream, well minus the current fault on ride height. Will post pics later but it's a standard LS430 99 plate. Future plans are just a nice set of wheels and tints, maybe a respray in the future.