I bought a SLX on Black Friday last year.  I have only fished with it maybe 10 hrs or so.  Honestly the heaviest action it has seen has been a tree snag and a snagged carp.  I'm getting quite a bit of gear grind and noise when there is any tension on the spool.  With slack line and the spool tension knob backed off it's much smoother.  I have disassembled, cleaned and lubed twice now and I'm still getting gear vibration and noise.  At this point I'm thinking there must be some play in the gears.  I'm open to suggestions on what I should do.  Could this be repaired?  Should I see if tackle warehouse or Shimano will take care of it under warranty?

Sounds like you have problem.  I fished mine for 5 hours on the Potomac yesterday and it was flawless.

Yeah I'd send it in. I have several and have had no issues.  It "feels" a little different with a load on it and I figure this is the lack of bearings in places and bushings instead of bearings.  Nothing that I've felt alarmed about tho I've been blown away by these little reels

Anybody know if tackle warehouse will let me upgrade?  Been eyeballing curado 70s anyway.

I'd say you're way outside the return period.  I'm sure shimano will fix it tho. Honestly dont think ur gaining anything with the 70. From my experience the slx is a smoother reel and u could upgrade it considerably and still be way under the price of the 70