Subaru Repair: Subaru Tire and Transfer question, subaru legacy outback, front wheel bearings

Question
Several months ago we had our Subaru Legacy Outback (97 with 175K) in the garage for a noise. Diagnosed as front wheel bearings so both replaced as well as front brakes. They said the rear tires were "chopped" due to alignment problem so replaced tires and aligned. Two months later, the car clunks when turning and makes a bad bumping noise underneath on the road. My wife was traveling out of time with the car and made it to the Subaru Dealer. Said dissimilar tires had ruined the electronic unit that keeps all four wheels going the same speed. Went back to the local garage that had done the original work and they deny that tires are the problem and hence any responsibility. They tell me that Subaru has a mechanical problem and that the tire issue is an excuse. Who is right? Thanks in advance. AGM

Answer
Unfortunately for the auto repair shop the dealer is correct. The problem with most All Wheel Drive vehicles is that you need to replace all 4 tires at once. That way the tire circumference is the same on all wheels. Subaru's do not have a "mechanical problem" as the shop says. If there was the dealer would have released a TSB (technical service bulletin) to you advising you to bring the vehicle into the dealer for repair. If you continue to have issues with this auto repair shop, you can always contact consumer affairs for your state.