2002 chevy trailblazer

I have a 2002 chevy Trailblazer that when you put it into drive there is a vibration.It does not do this in park or neutral.I have checked the engine mounts and transmission mount, and they look good.The vehicle has a little over 118,000 miles on it and the engine runs and drives great except for this vibration that i do not know where it id coming from.Anyone got any idea’s as to what may be my problem? Thanks

Well, its anything from bad motor or transmission mounts through to a poorly running engine at idle (even if you can’t tell while driving normally). On the former, I’m not sure what you did to check the mounts, but a mere static visual inspection will rarely tell you much about how the mounts are doing. On the latter the possibilities are endless - how old are your plugs & wires? Air & fuel filters? Check the fuel pressure. Check for vacuum leaks. Do you have a check engine light on?