2000 S80 Wheel Spinning Problem

I have a 2000 Volvo S80 T2.9 and I recently had to replace 4 tires because I was loosing tread in uncommon places, like on the outside of the rear tires and the middle of the front tires. I had the rear wheel bearings replaced as well because loud noise and vibration in the rear tires.

I bought 4 used to tires and had to upgrade to 225/60/16 tires because that was the only tires the dealership had used (I wanted 4 cheap tires). As soon as I picked the car up and drove off the lot and started to accelerate the tire slipping light came on in my dash and I was pushing the accelerator and the car was not accelerating. The past couple days this has been occasionally happening when I am going about 15-30 mph. I let off the gas and kind of tapped it till it started going again. This does not happen all the time usually just within the first 10 minutes of driving, then it will not happen again. When it does happen the RPM's do not rev up like the car is in neutral, the RPM's stay normal and I just coast until the tires start accelerating again. Any thoughts what this could be? Are the tires too big in the front?