I *think* even a small difference is enough to inhibit regen if the rears are smaller than the fronts by any amount - With the rear wheels turning more revolutions compared to the front than the computer thinks is normal, it assumes (I assume) that the rear end has lost traction, so adding regen to that mix would be dangerous
MelloYellow put rears on which were about 2% larger than the fronts he was using and had no problems with regen
When Carolyn poked a hole in a rear tire, I put a 195/55R14 on the car to get it home and had no regen . . . . and no other warning lights either. The car drove pretty much normal, but boy did it coast!! . . . . even in B mode
Don
MelloYellow put rears on which were about 2% larger than the fronts he was using and had no problems with regen
When Carolyn poked a hole in a rear tire, I put a 195/55R14 on the car to get it home and had no regen . . . . and no other warning lights either. The car drove pretty much normal, but boy did it coast!! . . . . even in B mode
Don