I have a California King Simmons BeautyRest mattress.  I got it in 2005 so it's 4 years old now.  For the last year, it has been hurting my back because it sags.  If I sleep more than 6 hours, I have back pain.  And I'm in good shape and have never had back pain before.  it's terrible.  I looked at Simmons website for their warranty process and it seems to be bogus to me.  They make you measure the depression with two rules, it's just a stupid thing.  It's a pillowtop, first of all, so if I measure it without "applying any pressure" like they say, that's ridiculous.  My back hurts and it's because of the sag, for sure.  So measuring the fluff of the pillowtop is useless.  I don't know how many inches my body sags, but it's way more than 2 inches.

So I'm wondering what is the best strategy to use here?  The place I got the mattress doesn't really have any kind of cooperative return policy, so that's not helpful.  I'm going to get a new mattress for sure, but I'd like to get a little cash or credit from this one.

I will never get pillowtops again.  The underlying support of the mattress may be fine, but when the pillowtop gets depressed, it doesn't matter what's under it.  I can't wait to sleep well again.

You are probably out of luck their.  Most companies warranty against 2" of depression.  A mattress is not designed to provide 0" sag.  There will be an impression eventually no matter what your warranty says.  Even if you do get an accepted warranty claim, you will most likely be responsible for shipping cost to the factory.  Can you measure the depression?  It may be working properly.  You could have just picked a mattress that does not suit your body type?  I wish i could help you more.  If you shop online, alot of places offer sleep trials to try and alleviate things like this.

Not unusual at all.  Good luck on the warranty thing.  Chances are they won't but you can try.
You can cut open the pillowtop and do your own cushy stuff inside.  Don't waste your money adding toppers because they only make things worse.
Kait

I think you guys are right.  I won't get anything for it.  I will never never never get pillowtop again.