On the 986 Boxster, the 996, and the 997, the radiators and A/C condensers sit in the front corners behind the bumper openings. Leaves and grit pack into those corners. They hold moisture against the fins, the aluminum corrodes underneath the pile, and the first sign is usually an A/C that blows warm in stop-and-go traffic or a temperature needle that creeps above its normal spot.

The fix is plain work. Bumper off, corners cleaned, condenser and radiators checked for leaks and soft fins. Do it before summer, not during.

→ Porsche A/C repair

Weight is why a Cayenne goes through pads and rotors faster than the sports cars. An early Cayenne S weighs close to a ton more than a 986 Boxster, and its brakes absorb all of that at every stop. Expect rotors with pads more often than not.

Fluid runs on a calendar. Porsche's schedule calls for new brake fluid every two years, regardless of mileage, because the fluid absorbs water and a wet system can boil on repeated hard stops. A soft pedal on the third stop is the symptom.

→ Porsche brake repair

The all-wheel-drive Cayenne sends torque through a transfer case and a long driveshaft held up by a center support bearing. Both wear out. A vibration that builds with road speed, or a drivetrain warning on the dash, points to one or the other, and mismatched tires make the transfer case work harder than it should. Read the fault memory first. Then put it on the lift.

→ Porsche transmission and drivetrain repair

The dealer isn't your only option. The Federal Trade Commission says it's illegal for a dealer to deny your warranty coverage because you had routine maintenance or repairs done by someone else. The same protection covers a BMW or a Mercedes-Benz still under its factory warranty.

That matters most on the cars still young enough to be covered, such as a newer Macan or Cayenne. Keep the paperwork from every visit, and the record speaks for itself.

→ independent BMW repair