I have a 2000 S80 T6 which has been quite reliable.

I replaced the entire brake system and bled the fluid several months ago, replacing the front pads and rotors with stock parts, and the rear with stock rotors and Mintex pads. I did the work myself, and it has worked great all of this time.

Anyway, today I was killing some time in the shop, so I thought it wouldn't hurt to rotate the tires. I swapped fronts for backs, keeping them on the same side. I torqued the bolts to 105lb-ft with my torque wrench, in a 'cross' pattern.

Ever since I put the wheels back on, the pedal seems 'softer' and goes down further before grabbing. It can push it nearly to the floor before the pedal stops. It feels exactly like it did when I first put on the rotors/pads, but evidently it went away within a few days as it's been firm ever since. Is this something I should worry about, or will it go away as well? There are no warning lamps lit, and I have just as much stopping power as before, the pedal is just softer. I can't imagine what could have happened. I didn't open the system at all, other than checking the little rubber 'hats' on the bleed screws to make sure they were securely attached. The brake fluid level is unchanged.

Also, more importantly, I seem to be having a problem with my alternator. It has recently gotten cold here, but I had the battery tested and it is fine. Whenever the engine is over about 1200RPM, everything is fine, but when it drops below that, the lights dim a fair bit and all the lighting starts to 'pulse'. When I bring the idle up, the lights get brighter immediately. I tried putting my battery charger on, and let it get about 2/3 full (I left the key on too long and it died). I drove it outside, and the lights were bright. When the battery drains again, it will probably start doing the same thing again. Also, some times the starter is extremely slow, almost to the point of not being able to start the engine. Since the battery has been tested to be good, I'm assuming the problem is the alternator. Am I correct in this assumption? As well, once in a while, when I'm idling and getting the 'pulsing' of the lights, it is accompanied by a high-pitched sound coming from the front of the car which raises and lowers pitch in time with the lights.

Thanks.

Scott