Is my battery toast?

[temccarthy1]

I have a 6 year old deep cycle battery for my TT. Has always worked fine even though we are always hooked to electric when we camp.. When I pulled the battery a couple weeks ago when I winterized the TT and put the battery in my garage to charge it ( haven't used the TT for several months) I noticed the water levels were low in several cells and the plates were not covered on 3 of the 6 cells . I added distilled water and filled them. On the charger I noticed it is making a bubbling noise and the battery is warm. Is this battery toast? Did the water levels get too low and the almost half gallon of water caused damage? Or am I kidding myself with a 6 year old battery?

[wkamper]

Take it to an auto parts store to have it tested but, it is more than likely 'toast'.