I like to perform my own maintenance and repairs but need accurate information to do this.

the car shakes and shutters during take off and acceleration.. we took it to the dealer and they have had it 8 days and have replaced the torque converter and now blame it on exhaust..
this car has alot of problems including the exterior lighting constantly needing new bulbs. The dealer seems to not care how long they are taking and i can assure you we will never buy a Toyota again..

How large a snow tire may I safely use on all four wheels?

Vehicle does have a rear camera mounted activated when backing up. It has taken 5 weeks to "research the issue and possible remedies--this will be at the selling dealer's expense-Are there really equivalent systems or can this system be obtained from the factory?