Hi all,

I bought my '99 5.9l half ton a little over a year and a half ago. I had the previous owner install a NEW air conditioning compressor just before I bought it. He had the local Dodge dealership do all the work. AC worked great all last summer, it was ice cold.

A few months ago the compressor developed kind of a grinding/rattling noise. You can hear it grinding from the outside while the truck is idling, and from inside the cab, whenever the compressor kicks on there is sort of a rattling noise. I never really paid attention to it because it was winter, and AC was the last thing on my mind.

It's been hotter than **** here for the last week so I tried to turn the AC on. I come to find out that it doesn't work at all. The air coming out of the vents is the same temp as the outside air. I know nothing about how AC works so any help is appreciated. I do have a vacuum leak somewhere (my trucks vents are possessed, turning on and off at their will). Could this be a problem? Thanks in advance.

 

The vents probably aren't the issue. Start your truck, turn the A/C on full blast, pop the hood, and see if the compressor does anything at all. If not, probably need charged... Only trouble there is..... given the noises the compressor was making..... no guarantee that simply charging it is going to be the end of the issues. I suspect your "new" compressor took a dump... I doubt that the dealer will warranty it at this point.

You can get a can of R134a at wally world for around 30 bucks, hook it up, and look at the gauge, if there is anything in there..... shoot in some more, and see what happens. If the system is empty...... chances are good it is NOT going to be a cheap and easy fix.

 

mines doing the same thing and i added a can of the freon to have a/c for 2 days, then it was warm again....i have a feeling it could be a leak towards the evaporator...is yours rusty? the smallest pinhole in any of the lines or anything can kill the a/c

 

if the system lost it's charge it is probably not circulating the PAG oil and damaged the compressor.
i had the same problem you described, compressor started making noise, shortly after, the pulley would start heating up and cause a burning smell. on the way to buy a replacement it got hot enough to melt my serpentine belt and snap!
once i got it home though, the replacement was easy. you need to add some PAG oil to the new compressor....then i took it to the EZ lube for system charge.

 

Thanks for the response guys. The compressor (or is it condenser???) kicks on every 10 seconds or so, then shuts off after about 2 seconds. It makes a "wobbling" noise that is easily heard inside the cab. It's harder to hear from outside just because of all the noises that the compressor makes. I'd rather not just throw a $30 can of freon at it if it's just gonna leak out after a couple days. Any more suggestions or is this more of a dealership kinda thing?

I need my AC. The black leather is nice most of the time, but not in this heat. The middle seat actually gave my date a 1st degree burn today. (She tried to blame the truck, but I just told her it wouldn't have happened if her skirt wasn't so skanky )

 

Boy, you sure know what to say to get those girls melting, don't you?

 

Well, you can blow the 30 bucks, blast some refrigerant in there, and see how long it lasts, or, you can pay someone else to do basically the same thing....

My A/C didn't work at all. Compressor wouldn't even consider engaging, until I had about half a can in there.... then it started to work..... after emptying that can, and half of another, the A/C now actually works. Not as well as I would like.... but, a whole lot better than "not at all".

 

It's a compressor because it condenses a gas to a liquid by compressing it. A condenser does it without increasing pressure.

 

Sure do! I find that being 100% honest is always the best policy

HeyYou, the compressor engages just fine, so is it safe to assume that there is refrigerent in there?

 

You said the dealer replaced the compressor and recharged it...how much you wanna bet they forgot to add oil. The automatic recovery and charging machines run out of oil and there is nothing there to tell you they ran out unless your smart enough to check before you hook it up, id bet a dollar your truck was filled without oil.