Mega cab Weak a/c

[ModifiedDiesel]

Does anyone know if the pulley on the AC compressor is the same size as the one on the gassers? I find in my truck that I have to keep the engine revs up above 2000 rpms to get decent cooling. Below 2000 the AC compressor can't spin fast enough to get decent cooling.



I would not be suprised if DC put a pulley designed for a gas engine with a redline as oppsed to our trucks 3200 rpm redline.



Friends of mine with Hemi's get frozen out of there trucks in the same weather my AC can't keep up.



Anyone know a decent place to get a replacement pulley for the AC so I can spin this thing faster?

 

[DPKetchum]

Good point. My neighbors 05 I've asked him about HIS ac. Always said it works good. BULL! went to lunch with him in his. Cools poor and after stopping at a stop light and starting off you get a burst of HOT air out of RIGHT VENTS like mine does. I called D. C. today and filed a formal complaint. Told them it WAS NOT A DEALER issue but a DESIGN issue and about ALL these threads and posts from 03 through 06s.

 

[RankRam]

This has become a really hot topic! :-laf



BTW I agree that the Mega Cab trucks are really lacking when it comes to sufficient air flow.

 

[BHaden]

Me Too. I bought the truck in Phoenix (06 MegaCab dually). I sold an 04 1500 QC to buy it. Right away I noticed the AC seemed not right in the 06. Same gripess; lots of noise, not much volume to go with it and it takes a long time to cool down. It pretty much stays on MAX all the time. I should mention, I'm actually living in San Diego, getting ready to retire to Flagstaff in a few years. It only gets in the 90-100 degree

range here lately and the AC is still limp. The 03 I sold was a lot better. Maybe I'll check the 134a this weekend. Is there a sight glass anywhere on this thing like I've seem on older cars where you can look for "bubbles" in the refrigerant stream?

 

[DPKetchum]

Hadn't been a sight glass in a decade or more on anything. My 03 cools poor. All Third Generation Diesels have a ac issue. As I stated my NEIGHBOR said his 05 was just fine. Its not. Luke cool and after a stop and starting back off warm/hot air pours out of pass side vents. Call D. C. and start files. All it takes is a few minutes and a vin number and mileage. 1-800-992-1997

 

[Cummins Cowboy]

I wonder if you can persue lemon law proceedings

 

[blacksmoke10]

Mega cab Mini A/c

I did take my mega cab 06 out of overdrive the switch on the end of the automatic gear shifter. It does rev higher as you drive and it does help a little but still very poor a/c. I wonder if dodge ever reads these post or if they even care. They really need to come up with a fix, Or the big honchos better start unloading there stock. Because eventually this will get out and even if they fix the trucks at the factory that bad name stays around along time in the new show rooms. I was thinking about starting a data base where everyone could go and register so we would have everyones information and then let dodge know about it. numbers would talk. Not sure I have any extra time to do that. It would be nice to actually get a straight answer from dodge if anyone know anyone high up there. I also made a complaint and the guy on the phone said they were not aware of any a/c issues. So if we let them know hey there are many of us and yes you do have issues they would fix it and there name would would not be hurt any. I really do like my new mega cab just hate the a/c all the rest of the truck is very good.

 

[DPKetchum]

Call D. c. and complain as I did. Enough of us do that it will make a differance.

 

[COBRAJET]

I did a little research and a little driving today in my 2006 Cummins, my son's 2005 F150 extended cab and the neighbors 2004 F350 crewcab. It was 104 degrees in Dallas today... plenty hot enough for some AC testing. All trucks were driven for 20 minutes on the freeway and 10 through town. All were in recirc mode.



The coldest air we could get out of the Cummins was 48 degrees on the second fan setting with the system in recirc mode after running for 20 minutes on the freeway. It went to 50 and then 52 when the fan speed was raised. It was around 56 degrees on the second speed after the city driving and was requiring the fan to be sped up.



The F150 was at 41 degrees in 10 minutes of freeway driving... cycling the compressor It would still blow 45 degree air on high speed. In town it never went above 45 degrees on the mid level setting.



The F350 was almost identical to the F150 and not worthy of typing.



The Ford's both have higher freon capacities than my Cummins suggesting larger systems. The Cummins holds 30 OZ's, the F150 holds 34 and the F350 holds 40. That equates to capacities greater than the Cummins of 12% and 33%. The F150 is smaller inside than the Cummins with a larger system. The F350 is larger, but not 33% larger. Some of this could be attributed to line lenght and such, but with all three being pickups this has to be pretty insignificant. It would appear to me we simply do not have an adequately sized system. Both of the Fords provide plenty of cold air causing the fan speed to be lowered.



I have limo tint on my back doors and back glass and illegal 13% on the front doors. This is helping mine quite a bit I would imagine... at least it is keeping direct sun of my arm.

 

[blacksmoke10]

mega cab mini a/c

thanks cobrajet I think you did the research and you hit the nail on the head.



Its amazing how well the rest of the truck is engineered.



I also did some research on one of my chevy's the chevy has a 5 speed blower fan control switch. The dodge mega cab on the highest speed in recirc puts out about the same amount of air as the chevy does on 2. 5

there is no 2. 5 setting on the chevy but the mega cab a/c did put out a little more air that the 2 out of 5 speed but not quite as much as the 3 speed setting. So the air flow out of the vents is very low. Air flow is also very hard to adjust. the chevy you can turn the vent and then also adjust the height very well, as with the dodge very hard to adjust so the little amount of air even hits on you.

 

[DPKetchum]

Great post and facts,thanks CobraJet. Next time vehicle shopping another little bit of info to store and look into.

 

[JWilmer]

OK... went on a "family day" yesterday (alot of stops... alot of open doors... alot of dilly-dallying with 2 young boys)..... heat index was 106 degrees here in MN. (warm enough I think )... full cold... on recirc... . fan on #3... wife complained about being to cold... turned fan to #2... I was OK... still getting low 50's from the center vent... . wife turned her vents up and away (still too cold) wife misses the dual climate control the Chevy had... . kids were fine in back.



AGAIN... I cant complain about mine... . its NOT the coldest A/C I've seen... but it is plenty cool for me and my family... IMHO... .



This was the hottest test temp to date... will leave it alone for now... it did well enough not to mess with it..... BJ

 

[opjohnny]

Has anyone checked the part numbers to see if the reg, quad and mega share the ac parts?, evap, cond comp ect?

 

[StricklandJ]

Not too cool MegaCab

I also have a MegaCab (3500) that I think doesn't have cold enough air. I am going to try the dealer for airconditioner fix when I take the truck in for the two recalls that have already sent out. I live in Indiana and today it is 95 and 90 percent humidity for a heat index of about 105. You better bet if you truck is setting in the sun it will be cooking inside. I have extra tint all around and use sun deflector in front window when parked. My truck is Atlantic blue in color so it is not a real dark color either.

 

[sonorakitch]

Well, after reading this thread for several days and growing accustomed to my new MegaCab, I really wanted to believe I had a problem too. What I have found however is that my AC works real well. 111 yesterday here in Phoenix, and while it takes 5 or 6 minutes to really cool me down, it seems to work fine.



Considering my truck was built in June, maybe DC adjusted things to make it a bit better? I cannot figure out why mine works great and everybody here seems to have problems.



~Chris

 

[COBRAJET]

The very dry climate in AZ. is helping your AC out quite a bit. It is a lot easier to cool dry air. It is a lot easier to heat it as well. You are 110-115 in the daytime and still fall into the upper to mid seventies at night. It was 104 here today with a low of only 83... hotter than that in the city. You are getting a nice 30-35 degree swing. We are lucky to get 20... high humidity. The temp can not fall below dewpoint so we wake up to nice muggy mornings... working the AC right off the bat.

 

[COBRAJET]

Not to change the subject... but 95 degrees and 90% humidity never exists. The heat index if possible would be over 140 degrees. 95 degrees with a heat index of 105 would be around 50% humidity. It is very difficult to have temps rise without a lowering of the humidity. It is the most humid early in the morning since the temps usually fall at or just above dewpoint which is as humid as it gets. A heat index of 105 is very uncomfortable.

 

[rwerner]

I just got an 06 MegaCab and you are correct the AC sucks. I live in Pahrump NV and it gets hot here and this thing barley cools the cab down.

 

[SKing]

OK this post made me turn into Dick Tracy. What I found in MY mega cab was that the voltage to the blower was not the same as my 03. After further investigation I ran the full voltage to the blower like my 03 and the blower blew way faster. I have wired a new power wire with a relay to the ignition and have way more blower speed on all control levels. I also evacuated my freon and replaced it with synthetic freon and also added a coolant additive and it cools like an ice box. I did this to my 03 a while back and have had some freezer cold temps in it since. I will pull some temp readings on the mega in a day or so. I worked on this project for 5 hours tonight and I need a beer. :-laf

 

[JWilmer]

Not to change the subject... but 95 degrees and 90% humidity never exists. The heat index if possible would be over 140 degrees. 95 degrees with a heat index of 105 would be around 50% humidity. It is very difficult to have temps rise without a lowering of the humidity. It is the most humid early in the morning since the temps usually fall at or just above dewpoint which is as humid as it gets. A heat index of 105 is very uncomfortable.

That is what we get in MN. hot and sticky!! (humidity gets high when its gonna rain... . dewpoint can get high with air temp and no rain)



The funny thing is Tower MN. record low is -61 degrees (air temp)... . this last Saturday was a +104... . HMMM nice temp swing here ehhh???-LOL



The joke up here is... . "If you dont like the weather... just wait a minute it will change"



Case in point..... Sunday was brutal... 106 degree heat index (95 degrees and 76 degree dewpoints) and Monday was 91 and I turned the A/C OFF in the house... why??? the DEWPOINT dropped to the high 40's by late afternoon = very comfortable... . BJ