Ford issues TSB warning against modifications and aftermarket parts for the 2011+ Mustang
When Ford issues a TSB, it’s usually to correct an existing problem or defect with a car. For example, up until now Ford has issued three Technical Service Bulletins for the 2011+ Mustang to correct problems with the clutch, fuel pump and cold shifting. The latest TSB, however, is curiously different. It addresses the fact that “some 2011 F-150 and 2011-2012 Mustang vehicles equipped with the 5.0L engine may have unauthorized modifications to the powertrain hardware and/or calibration which may result in exceeding component design limits. Such modifications could cause damage to the powertrain and/or void the factory powertrain warranty.” In addition, ford says that “attempting to increase the engine output via recalibrating the PCM may result in poor drivability, DTCs, or component failures.”
A Ford representative, when asked about the TSB, told us that “customization is a big part of the Mustang ownership experience. This [TSB] is designed to alert people to the possible damage and warranty ‘voiding’ one can incur if they modify their vehicles beyond factory specifications.”
Ford has told service technicians to “inform owners that the current 5.0L calibrations adjust fuel and spark settings for maximum performance with production hardware, while protecting the engine over a wide range of operating conditions. This includes a knock sensor calibration enabling optimized performance based on fuel grade usage – see Owner’s guide for details. Aftermarket hardware and calibrations risk damage to the engine.”
In addition, Ford technicians are advised to look for excessive cylinder pressure and temperature (piston damage, spark over-advanced, insufficient enrichment and catalyst damage), increased RPM limit (piston damage, connecting rod damage, oil pump damage, catalyst damage and clutch damage), and knock sensor calibration changes (piston and/or ring damage due to improper knock control). Technicians are also advised to look for common aftermarket parts including intake systems, superchargers, nitrous systems, throttle bodies and exhaust systems.
Here is a flow chart that technicians are supposed to follow when finding a failure consistent with aftermarket modifications:
So what does this mean for owners of 2011+ Mustangs? First off, know that Ford can’t automatically void your warranty due to aftermarket modifications. The Magnuson-Moss Warranty Act of 1975 states that it must be proven that an aftermarket part directly caused a failure to original equipment parts to void a warranty.
However, if you are going to modify your car, whether a simple tune, exhaust system or a supercharger, know that not all aftermarket parts and products are produced with the same quality. Increasing horsepower and torque can be done safely, but it can also be done in a way that harms the engine’s internal components. If an aftermarket tune causes an engine to run lean or if excess boost from a supercharger breaks a connecting rod, then Ford can legally void a powertrian warranty.
The lesson? Modify with care, and make sure to do your research before you buy aftermarket parts. Make sure to read the fine print. Some aftermarket parts are designed to exceed the limits of the factory parts and require additional components to handle the increased performance. Overall, aftermarket products designed and produced correctly will safely provide increased performance for your Mustang without damaging the factory components and will not void your warranty.
- Ford issues TSB for 2011+ Mustangs to resolve cold shifting problems
- Ford issues TSB regarding clutch problems for the 2011 Mustang GT
- Ford issues TSB for 2011 Mustang regarding fuel pump problems