Well I installed my trucool 40k transmission cooler and everything was going fine for a week until my A/C started to make horrible sounds. The belt tensioner starts flexing and making the sounds at anything over 1600 rpms with the ac on. I took it to an ac guy and he said the head pressure is at approx 350 psi at idle. We sprayed the condenser with water while the truck was idling and it lowered it down closer to 270 psi and it wouldn't make the noise until around 2500 rpms. He basically told me that the transmission cooler was restricting the air flow so much that it was causing the ac compressor to work harder/pressure higher/ and the tensioner to make the noise. Has anyone had this problem? I'm stumped because a ton of people run this tranny cooler

 

Nope, it shouldn't do it. If it did, you'd have overheating problems because your radiator wouldn't see enough air either. How does your fan clutch work?

I would lean toward a plugged orifice tube/filter or an old drier. 275psi is the MAX operating pressure allowed on the system, so if water only got it to 270, you have some other issue most likely. On a 90* day, I'd shoot for a high side pressure of 255ish.

 

Find a different A/C guy. The trans cooler is not your problem.

 

The fan clutch works fine. I'm going to take it to another guy this afternoon and see what he says about it.

 

Been running one for 8 years now and have towed heavy in the Texas heat with no problems. Go to another guy.

 

Good advice here, your trans cooler isn't your problem. I'd suspect a clogged orifice or drier as mentioned above. Just for ***** and giggles, you can unbolt the radiator and look to make sure that there isn't and debris between the rad and condenser, but as also mentioned above, you'd more than likely be experiencing a hot running/overheating engine along with poor ac operation.

What were the low side pressures at? This can help us help you, if the guy that you see today is a dolt also. If the low side is high also, the system is overcharged, which means that somebody either topped off or did an evac and recharge and put too much R-134a in.

 

I forget the exact reading of the low side but he said the reading was normal. He also said that if the system was clogged up it would have a low, low side reading and a high, high side reading. Does that sound right? I doubt the free on level is off because I've had the truck for 3 years and have never touched that.

I took it to a different guy today and he wanted to change out the complete a/c system (compressor, dryer, & condenser). I don't think I need a new compressor because is still cools fine but I could be wrong.

 

if a tranny cooler caused it id hate to see what that guy would have said about someone with a big front mount intercooler blocking the radiator, lol.

 

90* day.

2000RPM
255PSI High side (fluctuates on and off)
15-30PSI Low side (fluctuates on and off)

On these trucks the low and high sides are 8 inches from each other with an orifice tube in between. Again, if water only got it to 270, you have a problem that is not from too little air.

Since you have too much pressure, anyone wanting to replace your compressor is ripping you off. Don't go to them.

 

That is correct, if there was a clog, the low side would show a low reading on the gauge while the high side would be high.

So we have a high high side reading, and a normal low side reading...I'm racking my brain to try and remember if I've seen that before and nothing is coming to mind. I'll bet that it's something simple...

Did you unbolt the radiator and check for debris between the rad and condenser, just for poops and giggles? Only takes a few minutes and will rule out one possible problem....

You don't need the "whole system" replaced...that's what someone does who doesn't know how to properly diagnose the problem and wants to just rule absolutely everything out. I dunno, maybe he's thinking that the compressor took a dump and the system is full of shrapnel, but if that were the case, the high side should be low, and your ac wouldn't be blowing cold air...