Air Conditioning Repair

I have a 1999 Lexus GS 300 with 107000 miles. The air conditioning just failed and the problem was diagnosed by a dealer as a failed compressor clutch. The difference in price between a clutch and an entire replacement compressor assembly is less than $200. I’m guessing replacing the clutch is more labor intensive than changing the compressor unit. Is it better to change the whole compressor assembly rather than the clutch alone?

It’s far more labor intense to replace the entire compressor. Replacing the clutch is simple and will not open a big can of worms like replacing the compressor. I would just replace the clutch.

Get a second opinion/estimate at an independent shop but often changing the AC clutch requires discharging and removing the compressor, making it relatively more economical to replace the compressor. I wouldn’t replace an AC clutch on my own vehicles these days and the labor is real cheap.

Also, when the clutch fails many independent shops will forego replacing the drier and expansion valve with a new compressor.

What he said. If the clutch can be replaced separately, without having to evacuate the system, that is by far the preferred option.

If the compressor clutch failed where it didn’t damage the clutch bearing mounting boss on the compressor, it’s far cheaper to just replace the compressor clutch assembly.


The clutch only is much cheaper but there’s the issue of the compressor shaft seal. Given the age and mileage it would not be unheard of for a shaft seal leak to develop at any time; say a week after the clutch is replaced.

Changing the shaft seal kit then leads to the discharging and recharging of the system though.

Is it the clutch pulley bearing that is getting noisy or failing? Usually the clutch plate and the pulley do not have problems. There is the clutch coil behind the clutch pulley that can open or burn out.

In any case, it is fairly simple to remove and install the clutch assembly if there is clearance to work and the shop has the special tools.

If you have to change the shaft seal, the only repeated work that has to be redone is popping the clutch disc off that shaft. So replacing the shaft seal is not a prophylactic change at this time.


I vote for replacing the complete AC compressor

Your car is 14 years old . . . the compressor will have some wear by now

Those Denso compressors sometimes have a worn “snout” . . . the part the bearing rides on

If you’re determined to save money, make 100% sure the snout isn’t worn, and make 100% sure the compressor seals aren’t leaking

I would get a second opinion to make sure its not just the compressor clutch relay. Its a $15 part from an parts store like Advance auto Parts (AutoZone doesn’t carry it) or $107 from the Toyota dealer. It takes about 5 minutes to change. It is located in the underhood fuse relay box.

The underside of the relay box cover has a diagram identifying each relay. Just pull up on the one marked AC until it comes out, then plug in the new one. almost as easy as replacing a light bulb.