So just this weekend the reverse went out on my tahoe. I didnt notice any signs of slipping or anything before this happened. I can hear and feel the transmission shift into reverse, but it seems to just barely move and I have to help it by pushing off the ground with my foot. I did check the tranny fluid and it was kind of gray and a little low so I topped it off. I did change the filter about a month ago. Any help would be appreciated.