Aluminum nuts on the valve stems completely disintegrate and fall apart causing tires to go flat while driving. This happened on two occasions (two tires) while driving down the highway. Luckily we were able to get off the road quickly without incident. All 4 valve stems were inspected

- Baltimore, MD, USA

During the spring of 2013, my 2009 cpo Volvo S80 experienced two flat tires within one week due to faulty hex nuts (I.e., hex nuts broke off causing sudden loss of air pressure) that hold the tire valve stem to the wheel (Volvo incident #130404-000103). Volvo recognized the problem by replacing the tire and all fours hex nuts as a third hex nut was visibly cracked and the next likely culprit of a future flat tire. However, on July 25, 2015 almost two years later, I found myself once again driving on the interstate, when the TPMS light came on again stating, tire needs air now. I immediately pulled the car over on the shoulder and inspected the tires when I noticed the left rear tire was flat due to a broken hex nut. While I appreciate the overall safety features Volvo cars provide, they are fully negated by the faulty hex nut. There is no good in having one of the safest and reliable cars if you cant even drive it unless you want to risk being in a crash. I think its safe to assume that most people, who buy a Volvo, buy it for safety and not to experience reckless driving as a result of faulty parts. This part should have been recalled the first time around. Hopefully, appropriate action is taken to successfully recall and remediate these faulty hex nuts to avoid any unnecessary car accidents with other Volvo vehicles with this part.

- Volo, IL, USA

Valve stem locking nut corroded on left front wheel and separated from stem. The stem actually fell inside the wheel causing a blow out. No injuries, but this could have been serious at highway speeds. The defect happened at 45 months, and 51,000 miles. Subsequently all stems and sensors had to be replaced prior to 48 months. Per the tire dealer and grudgingly by Volvo, this is fairly common for that vintage of stem and sensor. Volvo did not honor warranty because the failure happened 1000 miles outside of mileage warranty but inside the 48 month timeframe, very poor service from a company that is supposedly known for safety. I find it ironic that a mandated safety feature barely lasts through the warranty period, and the failure mode causes the problem it was "designed" to prevent. Replacing the sensors cost about $150 each, or at least $600 for the life of the car.

- Troy, OH, USA

One of the nice safety features on this vehicle is the tire pressure monitoring system (TPMS), which detects under-inflated tires. Driving on under-inflated tires can affect a vehicle's handling and stopping ability resulting in a crash. Last week my pregnant wife was driving the car (daughter in the back seat) on a busy highway when all of a sudden the TPMS light came on and stated, "tire needs air now." So my wife got off the busy highway and called Volvo roadside service for a tire change, as the left front tire was completely flat. We took the flat tire to a mechanic, who noticed that the tire valve stem was inside the wheel, so he replaced the tire and tire pressure monitoring sensor. Yesterday, I was driving the car on the interstate, when the TPMS light came on again and stated, "tire needs air now." So I pulled the vehicle over and called Volvo roadside service for a tire change, as the left rear tire was completely flat. Two flat tires within one week and both with the tire valve stems loose inside the wheel. Now I realized the problem is due to faulty hex nuts, so I checked the vehicle and notice that the right rear wheel had a cracked hex nut. This is not a coincidence, as three out of four hex nuts were faulty. This faulty part has caused unnecessary damage and costly repairs. The reason we have a Volvo in the first place is for safety; however, my concern is that Volvo is using inferior hex nuts, which could cause unexpected flat tires resulting in a car accident. The faulty hex nuts are a "ticking time bomb" and feel it is my civic duty to inform Volvo and the appropriate authorities of this issue to ensure that any necessary action is taken to avoid car accidents as a result of this problem on other Volvo vehicles.

- Volo, IL, USA