wierd rpm drop while rolling

[deadbird]

When I'm driving and I take my foot off the gas, I can sometimes watch the rpms drop from about 1400 to 1100. When this happens the car jerks a little, slows down a little and lasts about a second before it jerks back up. It seems to only happen in 3rd. I have a 08 Sport automatic. I need a few ideas on how to tackle this problem.

[cobalt123]

dirty MAF um...clean your filters....