Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2011 Infiniti QX56 owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2011 Infiniti QX56. The contact stated while driving at various speeds, the vehicle would vibrate violently. Additionally, the vehicle had experienced intermittent power loss and had gone into limp mode. The contact stated that the check engine warning light was illuminated. The vehicle was taken to a local mechanic where it was diagnosed with needing the timing chain replaced. The vehicle was not repaired. The manufacturer was informed of the failure and informed the contact that the VIN was not included in a recall. The failure mileage was approximately 140,000.
Need to know if there are recalls on the Q56 Infinite for the Catalytic Converter Failure. This truck had 2 and this is the second one that seems to be faulty and the truck only had 162000 miles The 1st one faulted at [phone] The Infinite 2011 Q56 has been known for faulty Catalytic Converter Failure and nothing was done to recall and fix. The truck had 2 Catalytic Converters, the 1st one went out in 2024 @ 152000 miles, now it looks like my engine light is back on with error code P0420 Converter malfunction. I searched internet and it was noted that 2011 have had enormous reports about this issue. This doesn't make since there is no recall when it is noted that the 2011 Q56 had history of faulty Catalytic Converter Failure. This cost to replace and repair is enormous and this type of part replacement repair should not be happening at 152000-162000 miles. …
Catalytic Converter, A/F Sensor failed on the interstate when I was driving with kids in the car. Took vehicle to the nearest dealer only to be told that this is a known problem with these vehicles and it was going to cost me $3,100 to repair.
Through my research and speaking with Infiniti mechanics there has been a known issue with timing chains and associate parts that are a hazard and a major expense to 2011-2012 infinity QX56 owners. This issue will leave you stranded somewhere!! It happens to my wife and I three times!!! I had to get it towed all three times!! The hazard is while driving on highway the engine just loses all power leaving the hazard of someone running in back of you. If you driving up an incline and this problem comes about your vehicle will stall an you can possibly start rolling backwards. So from my research this problem has been happening to people either right before there warranty ends at 70,000 miles or right after (like me) at 74,000 miles. I called Infiniti and they refused to help me in any way. …
The SUV was driving without issue; however, if the timing chain had broken we would have had an engine stall which could have caused an accident. We heard a noise in the car and decided to be safe and take it in for service. After getting to the Infiniti dealership of gwinnett the noise had subsided. We explained we heard a whining noise when the car was starting up that went away after a time. The noise wasn't even evident but they knew what it was before even hearing it. After letting the car cool down they started the engine up again and heard the noise. They let us know this had confirmed the initial diagnosis of a timing chain issue. After getting home and looking up the issue with the car I was surprised to see so many people talking about this issue. Apparently Infiniti has a defective oil pump that lubricates the chains that caused this issue. …
The service engine soon light came on, and I brought the vehicle to holmon Infiniti in mapleshade, nj where I purchased the vehicle. The diagnosis was a bank 2 catalytic convertor failure. I had it replaced at a cost of $2,661.79 on Thursday March 29, 2018. On Saturday March 31, 2018, the bank 1 catalytic convertor failed. Infiniti consumer affairs provided some assistance with the second repair. They paid for the parts and I paid the labor of $1,385.63. Infiniti consumer affairs would not reimburse me for the parts for the first repair because "I already paid for it". Had I known about this apparently common problem, I would not have paid for the first one without contacting them first. It appears to be a known issue if they were willing to give me any assistance at all, and I would think that would be extended to repairs already paid for by the consumer.
Today, I was told that I have to replace the catalytic converter, which going to cost me $2,000. I am the original car owner. I researched other sites and it appears there catalytic converter issues on Infiniti 2011 - 2013 QX56 vehicles. Please look into these websites. There should be some type of recall for these vehicles regarding the catalytic converter. Refer to websites: https://infinitiforum.net/Infiniti-forum/archive/index.php/t-13616.html https://repairpal.com/timing-chain-and-exhaust-stay-away-from-infinit-QX56-and-better-stay-from-all-Infiniti-cars--314 https://forums.edmunds.com/discussion/35247/Infiniti/QX56/2013-QX56-catalytic-converter-premature-failure http://repairpal.com/abnormal-noise-from-timing-chain-area-266 please consider a recalling the catalytic converter on these vehicles.
Tl* the contact owns a 2011 Infiniti QX56. While driving 60 to 65 MPH, the vehicle jerked and an abnormal noise was heard from the engine area. Also, the service engine indicator illuminated. The contact had to decelerate due to the noise. The contact drove the vehicle to an independent mechanic to be diagnosed, but no failure code was found initially. The mechanic reset the codes, test drove the vehicle, performed a second diagnostic test, and located failure codes for the timing chain, catalytic converter, and exhaust system. The manufacturer informed the contact that the vehicle was not included in the unknown manufacturer recall for the engine timing chain and catalytic failure. The vehicle was not taken to a dealer. The vehicle was not repaired. The approximate failure mileage was 200,500.
On June 1st 2020 I took my 2011 Infiniti QX56 to the shop for having the code p0087. The shop told me that I should take it to the dealership because the problems the vehicle is having are recalled under voluntary safety recall campaign. When I called my local Infiniti dealership they told me my VIN # doesn't doesn't show as recalled. They dealership provided me with the phone number of Infiniti consumer affairs. I called Infiniti affairs and told them about my vehicle they told me that they were sorry but my VIN doesn't show up on their system. The bottom line is that every single thing that I researched and find the wrong of the vehicle comes back with a voluntary recall. Like the fuel system, timing chain, vvt solenoids, high pressure fuel pump. I use vehicle in the city and highway.
Tl* the contact owns a 2011 Infiniti QX56. The contact stated that while driving on an incline approximately 50 MPH, the vehicle loss motive power with an abnormal sound coming from the engine compartment. The vehicle was towed to the dealer Infiniti of gwinnett, (3090 satellite blvd, duluth, ga 30096), to be diagnosed. The contact was informed that the timing chain needed to be replaced. The contact also stated that the vehicle was previously repaired in 2016, by hayes Chrysler/Dodge of lawrenceville located at (719 duluth hwy, lawrenceville, ga 30046), for a similar failure. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 169,000.
Engine complaints in other QX56 years
Frequently asked questions
How common are engine problems on the 2011 Infiniti QX56?
NHTSA has 39 complaints about the engine & cooling of the 2011 Infiniti QX56, 50% of the model year's 78 complaints. The component named most often is exhaust system › emission control › catalytic convertor (3 mentions).
Is there a recall for 2011 Infiniti QX56 engine problems?
No. NHTSA lists no engine & cooling recall for the 2011 Infiniti QX56, though it has 2 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2011 Infiniti QX56 engine problems start?
Half of the complaints with a recorded mileage happened before about 100,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.