capage58

Hello to everyone, I am a new diesel owner having just purchased a 2005 Ram 2500 4x4 with auto transmission. I have been lurking here for some time and trying to gain as much knowledge as possible. I do have one question.

When I first turn on my a/c after a couple of days of non-use, it makes one heck of a "clunk" in the compressor area, subsequent cycling does not produce this sound. This is not a daily driver for me so it may not be used for a few days at a time. Currently it only has about 400 miles on it.

Has anyone noticed this on theirs?

Many thanks, this is a great forum and I have learned quite a lot so far.

Regards,

Chris

Cat Cracker

Hello, and welcome! My truck does this also, it has approx 42k miles on it now. I asked my dealer about it, and ofcourse got the "thats normal" response. Hopefully others will chime in with their expierences also.

Cat Cracker.

tfarmer96

Same here mine has done it from day 1. I have had mine just over a year it has 21k on it. I have just gotten use to it.

scopedoctor

My truck is guilty too. After some time, not always, when the A/C is turned on, it will make the loud clunk sound.

Haulin_in_Dixie

My truck did it from new and still does it. It now has 340,000 on the original compressor. Guess it does not hurt it much.

phox_mulder

I've found if I can hold off turning the A/C on for a couple miles, it decreases the clunk quite a bit.

I guess letting everything turn for a bit lubes everything up enough, it still clunks though, just not near as bad.


phox

Hounddog

Mine does it also.When I bought mine I test drove several trucks,It was middle of the summer.They all did the same CLUNK with ac was flipped on.

capage58

Thanks for the reply's. I guess the "clunk" is nothing to worry about.

quantrill88

same here, although mine just started doing it. I used the A/C last summer right after I bought it but never noticed a "clunk"

capage58

As a follow up, I tried what Phox does and drove the truck until it warmed up and when I turned the A/C on the first time, no "clunk". I wonder why?

BlackSunShyne

My '05 (1900 miles) has the same "clunk". I have not tried waiting a few miles to hit the A/C, but I will have to give it a try. I dont recall my '98 having this "clunking" noise.

yycguy

same here 0ne heck of a clunk this AM

Cummins600

Mine just started to do the same thing. Didn't see this thread and started this one https://www.dieseltruckresource.com/...threadid=69518

by2005

It is the sound of the cold or fresh air doors opening under the dash. It is normal and seems to vary slightly from truck to truck and not always consistent. The doors may not always open all the way, depending on the temperature or where the controls are set.

Hounddog

Well the CLUNKS I heard and hear are NOT from the dash.There from the compresser.Only does after sitting long period un used and turning compressor on.Its no biggy as mine only does after long layups.SEVERAL I test drove in the summer heat did it but not again with on and off of system.Salesman said he had heard same noise on all of them on first startup and use of A.C. I believe him.