My wife and I are looking at purchasing a new Subaru Outback. In the manufacturer's specifications, it states that for the 2.5L (four-cyl), that the towing package allows us to tow up to 2,700lbs.
In contrast, the 3.6L (6-cyl) allows for 3,000lbs.
This seems really odd to me. For one thing, I don't think that a 2.5L engine produces enough torque to tow 2,700lbs. Additionally, if that were true, why wouldn't the addition of over 1L of displacement generate enough of a torque difference to tow more than an extra 300lbs?
When I ask the salespeople (and others) about this, they give me a hand-waving answer about how it "has something to do with the symmetric all-wheel drive and attachment to the frame at a lower center of gravity."
I understand that Subaru uses a Boxer-style engine, with symmetric all-wheel drive, but could someone give me a better answer (ideally with specifics about the physics of energy transmission in the drivetrain) as to why a Subaru 2.5L engine can tow 2,700lbs, but my current Mazda3 with a 2.4L can't really tow 500lbs?