not particularly a diesel question. but when thinkning of the summer to come,. i think i need to recharge my a/c.. now the part store said i need this and that and will come to about 3-400 bucks.. but could i just recharge it with the newer freon? i have heard somebody say that u could just plug it in, but make sure the old freon is all out first.. any advices would be appreciated.

ned