Anyone have any suggestions on disconnecting the top AC line on 04 mustang. Replacing heater core but can't get the quick disconnect tools to work on that larger AC line. Hope I'm posting to the proper place. First time on the site. Thanks
Those fittings can be a bear. Try pushing the line together and then fully inserting the disconnect tool. Pull the line apart while keeping the disconnect tool fully inserted.
On very difficult lines I have had some success using better metal disconnect tools.