clarehills

I have a 2003 GT and about half the time when I turn on the a/c I hear a clunk coming from the rear sounding like a heavy shoe being dropped into the trunk (I know). Any similar experiences or ideas?

Dan04COBRA

From the rear? There is nothing in the rear related to the A/C.

Anyone who uses their A/C hears a thunk from the dash occasionally. It's normal noise..

yoteehunter

Sometimes when the clutch on the compressor kicks in it will clunk but all A/C stuff in in the front of the car.

clarehills

Ya, thats what I thought but the noise is deffo coming from the back. Is is possible that it is causing some sort of backfire in the exhaust - that is like where the sound seems to be coming in... Thanks for the input lads.

Dan04COBRA

Your A/C couldn't cause any backfires. If it were seized it would shut your car off.

There is nothing in the back of your car related to the A/C.

Derf00

Check your motor mounts and tranny mount for wear, check exhaust for proper clearance. A/C will put a strain on the motor as it kicks on. Loose mounts or exhuast hangers (poor clearance) may cause the exhaust to whack the body and give you the 'thud'. Not likely but who knows.

Normally though...usually...A/C has nothing to do with the trunk. That's the only explanation I can come up with that would remotely link the two.

Dan04COBRA

The A/C will put a small strain on the driveline like Derf said. However if the A/C is enough to make a tranny mount or exhaust hanger clunk, I would imagine any amount of throttle would make it clunk too.

I think you just need to accept the sound as normal.