replacement cooling fans and radiator for GXP

[pdemondo]

I have a 2006 Grand Prix GXP. I have replaced the steering rack, water pump, harmonic balancer, and rewired the cooling fan with new external relays and larger wire. The old relay setup through the box was damaged in the junction box.

My newest issue is the cooling fans. The driver's side fan will not come on. I checked it with a volt meter, it is getting power but will not turn on. I know I can get a direct factory replacement for the entire assembly but I was looking at replacing both fans with higher flowing fans. I live in the Phoenix area so better cooling is always good. I realize that I will have to do some cutting of the shroud and fabrication to make them fit. Are there any fans that anyone has used that have proven a good upgraded to OE?

I was also hoping to replace the OE radiator with a 3-core aluminum radiator. I cannot find anything that is a direct fit but does anyone know of a radiator, like a Champion, or something like that which can be made to fit?

[91parkave]

Your first mistake was the understanding of the cooling fans system, it's pwm modulated not just a direct voltage to the fan. There not designed to be full on full off but if you wanted that way you'd have to use the 12v power to signal your relay and use another 12v source to power the fans.

I lived in arizona too and never had a problem even in Phoenix stop and go traffic. Your best solution for that is a tune from overkill to kick the fans on earlier

I would also get a good standalone cooler. To seperate the trans fluid and radiator fluids from eachother.

I can assure you, you do not need a 3 core radiator, when the stocker is more than adequate especially at stock power levels

[blueguy]

I noticed a decent drop in engine temps, not to mention the crazy amount of transmission temp drop after installing my big Tru-Cool 4590 and bypassing the radiator.

Worth it's weight in gold.

[pdemondo]

Thanks for the replies.

Following up, hopefully this information will be of use to others. The dual fan system on the GXP uses DC motors. The motors are controlled by the engine computer using three relays. The fans can be powered up either in series or in parallel.

I pulled out the cooling fan assembly. One fan is 12" (driver's side) and 14" (passenger's side). The depth of the assembly is a bit under 3" so finding any aftermarket fans to fit would be tough.

Examining the fan assembly I had two problems. 1. The driver's side fan connector was making intermittent contact. That would cause the driver's side fan not to work at all and also cause no cooling in low speed mode. 2. The other problem was that the driver's side fan was wobbly and would probably fail soon.

I went ahead and purchased a new OEM-type fan assembly and installed it. The car runs cool now even with the AC running.

I already have a transmission cooler installed. I would still like to add a larger aluminum radiator if I could ever find one that would fit.
Champion will make minor modifications to any radiator they currently sell to accommodate other applications.