A recent customer brought this 2013 BMW X3 from their home in Carlsbad into our BMW repair shop in Oceanside, CA, 92058 and mentioned that there was a loud grinding noise coming from the car, accompanied by a burning smell all while the car will not drive with a Check Engine Light on. After performing our free vehicle health inspection, we confirmed the vehicle does not drive freely, and there was definitely a hard grinding noise present when attempting to move the vehicle.
Inspection/Findings

We put the vehicle on and drove on rack, we were able to recreate the concern. After removing the vehicle’s under panels, we found the front differential had failed entirely and there was a big hole in the side of the casing. This is all resulting in a massive grinding noise when it is engaged.
Cause
It’s hard to say what the cause was… Whatever happened, it wasn’t good. Initially we thought it might have been caused by blunt force trauma by de, however, due to the location and lack of other signs of damage, we ruled that the possibility of this happening was very slim. Alternatively, this could have been the result of lack of maintenance and it internally failed, potentially prevented by maintenance if it was making noise or had low fluid. Friction could have caused it to get exceptionally hot internally and ultimately led to a failure and wild blowout.
We recommend differential fluid flushes every 50,000 miles as a best practice. While we do not know for sure if that is the exact reason that this rear diff failure occurred, had we replaced the fluid on time, the outcome may have been different, and at that point we would at least know that we had done everything in our power to avoid catastrophic failure such as this.
Replacement

In this situation, it will be necessary to replace the front differential, and as a best practice in a situation like this, we would be prepared to replace the transfer case, front driveshaft, and both front axles, since we cannot tell what kind of damage the other components have sustained while trying to drive the car with the failed differential.
We specialize in BMW repair in Oceanside, CA, 92058, if you are experiencing any grinding noise, burning smell on your BMW, we can take a look at it for you today!
Call/text: 760-721-5500
Email: [email protected]