this started about the last month and a half or so, but it's very sporadic. When it does happen, this is how it goes: put the car in Reverse, and step on the gas-the car goes very slowly in reverse and kind of sputters as it's in reverse. All other gears consistently engage just fine. I haven't found a common thread for when it happens, it's very random. Am I looking at a new tranny or perhaps something as simple as replacing the filter, and adding new fluid? The car as just under 149K miles on it. Any insight is greatly appreciated! Thanks in advance.