Two more questions on my new 04

[LightmanE300]

1. When you guys run the a/c, do you notice the fan also revving up with the engine when you take off sometimes, and it slowly goes away? My tahoe did this and it was annoying as heck. The engine appears very loud at first when you take off, but it's really the a/c or blower fan revving up with the engine. Is this normal, why does it do that??



2. What air pressure are you guys running in your 2500's?

 

[NManduke]

Mine does the same thing. The Pete does it too. It's the fan cooling the compressor. Normal.



For tire pressure I fluctuates according to what I'm towing. There should be a book with your truck. I follow it to the letter, or best I can.



JR

 

[Dean Upson]

The fan sounds like a light plane taking off when the a/c is on. Took a while to get used to it and I did . There have been many posts on this.



Dean

 

[gsbrockman]

To my knowledge, the fan noise is normal. The fan clutch is now an electronically controlled type as opposed to the older style mechanically controlled. I believe the fan clutch gets input from the coolant sensor and a/c demand. As for the air pressure, check the tire booklet. There's info for light load and full/max load recommendations. As a light load driver 95% of the time, I run 52 psi front and 42 psi rear in my LT265/70R17 BFG Rugged Trail T/A's.

Greg

 

[ttreibel]

The fan noise is totally normal and be thankful it does that, the AC works great when stuck in bumper to bumper traffic that way. The AC in these trucks is assume almost as good as my old 1976 240D that car would grow ice crystals on the vent fins, now thats AC!



With the fan spinning one speed the turbo spooling at a different factor in the engine and tranni noise these trucks really sound like a big rig much more than the other two offer.



I ran my tires at max pressure for about 2 months but went back to the recommended pressure. The ride was rougher and mileage did not improve and handling seems better at the recommended pressure. I leave mine set at the tow or haul inflation my truck is almost never driven unloaded.