Stock system
 

I just noticed that on the stock (4 speakers)system, the front speakers are 4 ohms and the back 6x9 are 8 ohms.
Anyone know the reason?

Thanks

Because GM is retarded like that! LOL

its becaue if you have a pioneer subwofer its tapped into the 6x9's if it was a 4 ohm it would bring the total ohm load of one of the rear speakers below the amps minimum ohm specs.

I think its different when you have the Pioneer system.
The stock 6x9's I took out of my deck lid were 2ohm
I think the 4 speaker system does not have an amp, or rather runs of the HU's internal amp.
As for a reason...Why ask why? Who knows why they do the sh*t they do, sometimes I think its just to mess with us

sorry i was backwards your right mine were 2 ohm as well. It doesnt matter what the impedance is on the speakers its what ever the cobalts amp runs at optimum level