A/C Vibration

[jman]

My A/C compressor seems to cycle on and off very hard. I get the same "clunk" when I first turn it on after is sets, but I can feel it cycle on and off when driving. If I am idling at a stop light it feels like you are starting and stopping a PTO on a tractor as you can feel the truck sort of torque when it engages.



It really gets annoying at about 2100 rpm as you can feel it kick on and off by the vibration in the throttle and steering wheel. It is bad enough that I think I could plug my ears and still be able to tell you when the compressor is engaging. I already had the TSB done that involves the steering hose, but it was done during the winter so I wasn't using the A/C much so who knows how bad it would be without it.



Just wondering if anyone else has had this problem or has any idea what it is.



Sorry so long.



TIA



jman

 

[rbattelle]

My truck has always behaved this way. I, too, can tell you when the compressor engages on the highway. It's the worst between 1800 and 2200 RPM at highway speeds. If you drive up past 2200 RPM you no longer notice the A/C cycling.



Many others on here have reported exactly the same thing, and I believe it is completely normal. In my opinion, the compressor is either very powerful or very poorly designed. Sometimes I'm embarrassed by it since my wife's little civic makes no announcement that the compressor is running.

 

[jman]

Well I guess I'm glad I'm not the only one. Is this something that Dodge is aware of and is working on a fix? My boss has an 03 auto and I have never noticed it in his, but with an auto it usually shifts before the bad rpm range so you wouldn't notice it as much since high rpm wouldn't normally be sustained except on the highway.



Hopefully enough of us will complain and a TSB will be issued.



Riiiiiiggggghhhhttt!

 

[rbattelle]

I don't think there will every be any fix for this. Since there's really nothing wrong with the compressor, per se, and there's no harm in a noisy compressor, Dodge doesn't have much incentive to issue a fix. Probably the only real fix is a whole new compressor manufactured by someone else. Personally, I think it's just a poorly balanced compressor caused by shoddy manufacturing and materials. Just my opinion.

 

[rscurtis]

I believe the fix for this is to have the updated power brake booster hose installed which contains a metal weight clamped to the hose. I believe there

is a TSB on this but I don't recall the number. Or, you can do what I did on

my '03, simply tie wrap the two hoses together(thereby changing their

individual mass) and the problem will be virtually eliminated.

 

[Bill Stockard]

It really gets annoying at about 2100 rpm as you can feel it kick on and off by the vibration in the throttle and steering wheel. jman

I took my truck to the dealer with the same complaint. I could feel the compressor vibration when it cycled on and was running in the accelerator pedal and the steering wheel in the 1,800 to 2,200 RPM band. The dealer’s tech found the bolts on the compressor weren't tight. After tightening the compressor mounting bolts up to proper torque specification, installing the replacement brake booster hydraulic hose, and tying the hoses together, the vibration is gone.



Bill