By Chris Chase, CanadianDriver.com

Introduced in 2004, the QX56 was the Infiniti’s first full-size truck, added to the lineup as a replacement for the QX4, a much smaller vehicle based on the second-generation Nissan Pathfinder platform.

2004 Infiniti QX56

The QX56 was based directly on the Nissan Armada, which in turn shared most of its dirty bits with the Nissan Titan full-size pickup. As such, the QX56 was powered by the same 5.6-litre V8 (315 hp/390 lb-ft) found in those two vehicles, backed up by a five-speed automatic transmission and standard four-wheel drive with low-range gearing. Note that U.S. buyers got the option of a rear-wheel drive model.

The engine’s output rose nominally in 2007, to 320 hp and 393 lb-ft of torque. In 2008, the QX got the expected interior and exterior styling update as well as some new standard features, like 20-inch wheels to replace the old 18s, and a heated steering wheel. The ‘08 model also got upgraded brake rotors intended to address wear problems in previous model years; more on that later.

Find a used Infiniti QX56 on AutoTrader.ca

Official fuel consumption numbers for the 2004 model were 18.1/12.1 L/100 km (city/highway); by 2009, those figures had improved to 17.3/11.8 L/100 km.

Consumer Reports only has data on a few model years for the QX56 and gives it an average used vehicle reliability rating based on what information it has. The very similar and more popular Nissan Armada gets below-average marks for most model years, however, indicating that there are more than an average number of trouble spots to be aware of.

Infiniti upgraded the brake rotors on the QX56 in either 2007 or 2008, depending on who you ask in response to premature wear and frequent reports of brake pedal pulsations and squealing noises in early models. It seems to have helped: Consumer Reports data on the QX in the “brakes” category shows an improvement between 2006 and 2008. What makes me curious, though, is that the Armada’s brakes get a failing grade all the way through, from 2004 to 2008, so either the better binders were limited to the upscale Infiniti version, or the fix wasn’t that effective.

There’s a common problem with the “variable blower control module,” an electronic piece that makes the automatic climate control work. One of the symptoms is a fan that will only work on high; the fix is to replace the module, which isn’t too expensive and is apparently quite simple to replace.

The QX56 stereo’s Music Box music storage is a source of frustration for many owners.

Consumer Reports notes tailgate troubles in its “body hardware” category. Water is known to leak into the tailgate and cause corrosion or a short circuit in the release switch, which leads to some weird behaviour. Check this thread at Forums.Nicoclub.com and this one at ClubArmada.com for more info. There’s also this issue, of the power-operated tailgate opening, and then immediately closing itself.

The QX56/Armada is very sensitive to out-of-alignment wheels, according to this thread at ClubArmada.com.

The QX56 uses an auto-levelling rear suspension. The system isn’t noted for being particularly trouble-prone in these trucks, but it will be an expensive repair if it does fail out of warranty. If this thread at ClubArmada.com is an indication, the suspension’s control unit and/or relays could be a source of trouble.

A QX56 that cranks but refuses to start, or stalls while the truck is being driven is probably suffering from a bad Intelligent Power Distribution Module (IPDM).

The Nissan Titan is known for differential problems, both front and rear, in four-wheel drive models, and the mechanical similarity between that truck and the QX56 would lead one to believe that this Infiniti might suffer the same problems. Indeed, I did find one mention of a QX56 whose owner complained of a front drive axle that refused to stay attached to the differential, something for which the Titan is reknowned. Note that the QX56 and Armada use an independent rear suspension in place of the Titan’s live solid axle, but the internals of the rear differential are probably similar, if not the same.

This thread at TitanTalk.com talks about the rear differential, while this one deals with the front differential problems. Consumer Reports notes some “drive system” problems in 2005 and 2006 Armadas, but doesn’t offer details. Remember, though, that the Titan is more likely to be subjected to heavy use; that, and the fact that the QX56 was offered in a 2WD model in the U.S., would be contributing factors in the lack of specific information, an actual flaw in the truck notwithstanding.

Consumer Reports also notes the sunroof as the trouble spot, but I couldn’t find anything specific about it on the web.

Only the National Highway Traffic Safety Administration (NHTSA) has crash tested the QX56, giving the truck four and five stars for driver and front passenger protection, respectively, in frontal crash tests on a 2006 model. A 2008 model’s ratings were reversed – five stars for driver and four for front passenger – but side impact protection was never tested. The Insurance Institute for Highway Safety (IIHS) never tested the QX56 at all. As is expected in a luxury vehicle, the QX56 came standard with front seat side airbags and head curtain airbags, as well as stability and traction control.

According to the Canadian Black Book, used QX56 values start at $25,700 for a 2004 model and range up to $49,100 for a 2009 version. This truck was available in one trim with virtually no options, so any example you find will be essentially loaded with items like navigation and power everything, so weigh your need/desire for luxury options carefully. If you can live without them, consider the very similar Nissan Armada, which can be had for as little as $18,650 used and with fewer standard features. Direct competitors to the QX include the Cadillac Escalade, while the Chevrolet Tahoe and GMC Yukon are less expensive versions of the Caddy.  The Ford Expedition, Jeep Commander and Lincoln Navigator round out the list of domestic comparables. There are a few other imports worthy of consideration, like the Mercedes-Benz R-Class and the newer GL-Class, and the Land Rover Range Rover is similar in its purpose, too, in terms of large, seven-/eight-seater SUVs.

Just about any vehicle in this price range will have loads of high-end features, and these will tend to be the source of most of the problems in any car. If you’re looking at one of these vehicles for its towing/hauling capabilities, I’d seriously considering foregoing some of the luxury gear in an effort to avoid pricey problems in the future. In the QX’s case, however, that means avoiding it altogether, given Infiniti’s single-trim packaging practice with this truck. If there’s no other truck for you, though, then do your research: read the forum discussions I’ve linked to in this article, and get to know what can and might go wrong in a QX56. Look for a used example that’s been well cared for and includes detailed service records and get the truck checked by a trusted mechanic who knows his or her way around complicated vehicles before buying.

Pricing

Black Book Pricing (avg. retail) June 2010:

Online resources

There are a number of places to turn to on the web for information about the QX56. There’s a so-so QX56 section at InfinitiForum.com, but it’s one of the less-busy spots I found. The QX section at FreshAlloy.com is good, as is the one at ClubArmada.com. I also found a number of useful threads and posts at NicoClub.com.

Recalls

Transport Canada Recall Number: 2008221; Units affected: 8,080 (includes other models)2004-2006: Certain 2005-2006 model year vehicles may have been assembled with an incorrectly manufactured air conditioning condenser fan motor, which could allow excessive water intrusion and inadequate drainage. If sufficient moisture accumulates in the motor, corrosion could occur, increasing internal friction, and thereby augmenting the electrical current draw. This could cause an increase in the motors operating temperature that could eventually melt its wiring insulation and other plastic components and form a gas. If two wires without insulation touch each other and create a spark, this gas could ignite and result in a vehicle fire, which could cause property damage, personal injury or death. Note: 2004, and some 2005 model year vehicles are equipped with a different fan motor that is not subject to this campaign. However, it is possible that a limited number of these vehicles may have received the subject condenser fan as a service replacement part, thereby being included in this action. Correction: Dealers will affect repairs.

Transport Canada Recall Number: 2010060; Units affected: 8,681 (includes other models)

2005-2009: On certain vehicles, the material used on fuel level sending unit contacts can wear and contaminate the sender. This causes the instrument panel fuel gauge to display that the vehicle still has some fuel left in the tank when the fuel tank is empty. An inaccurate fuel gauge can lead to engine stalling while driving, which may increase the risk of a crash causing property damage, personal injury or death. Correction: Letters will be sent to owners in two stages. The first letter will advise owners of fuel gauge inaccuracy and recommend maintaining a fuel level above the one half position. The second letter will follow, requesting owners bring their vehicles to a dealer for replacement of the fuel sender unit.

Transport Canada Recall Number: 2010062; Units affected: 6,246 includes other models)

2008-2010: On certain vehicles, the brake pedal pivot pin end was not properly manufactured. As a result, the pin may not remain in place, causing the brake pedal to partially disengage from the brake pedal bracket. If this occurs, the driver will experience unusual and noticeable looseness in the pedal and a reduction in braking force. A reduction in braking force may lead to increased stopping distances and the risk of a crash causing property damage, personal injury or death. Correction: Owners of all potentially affected vehicles will be contacted and their brake pedal assembly will be inspected and replaced if necessary.

Transport Canada Recall Number: 2010088; Units affected: 660 (includes other models)

2010: Safety Advisory: On certain four-wheel drive vehicles, the joint portion of the front drive shaft may contain small cracks. These cracks may eventually lead to a failure, resulting in separation of the front drive shaft. If the driveshaft failed while the vehicle was moving, a loud noise would be heard. If the vehicle were in 2WD mode, the driveshaft would come to rest on the frame cross-member, and the vehicle could be operated normally. The drive shaft would not come in contact with brake, steering or fuel system components therefore risk of an accident is considered minimal. Correction: Dealers will inspect the vehicle and replace the front drive shaft if necessary.

Crash test results

National Highway Traffic Safety Administration (NHTSA)

Insurance Institute for Highway Safety (IIHS)Used vehicle prices vary depending on factors such as general condition, odometer reading, usage history and options fitted. Always have a used vehicle checked by an experienced auto technician before you buy.

For information on recalls, see Transport Canada’s web-site, www.tc.gc.ca, or the U.S. National Highway Transportation Administration (NHTSA)web-site, www.nhtsa.dot.gov.

For information on vehicle service bulletins issued by the manufacturer, visit www.nhtsa.dot.gov.

For information on consumer complaints about specific models, see www.lemonaidcars.com.

Chris Chase is an Ottawa-based automotive journalist. He is a member of the Automobile Journalists Association of Canada (AJAC).

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