Long-Term Test: 2007 Infiniti G35 Sport

Why We Bought It
Durability
Performance and Fuel Economy
Retained Value
Summing Up

We've just finished our one-year test in the 2007 Infiniti G35 Sport, one of the most compelling sport sedans on the road. It's a four-door 350Z sports car, delivering a mix of speed and practicality that sets it apart from its competition.

This car represents the introduction of the second-generation G35, meant to be faster, more purposeful and even tougher than before. It's Infiniti's attempt to take on BMW in the most direct way possible. The right people must be listening, because G35 sales increased 18.2 percent to 71,809 sales in 2007, an indication that Infiniti is getting its message across.

But 20,000 miles behind the wheel of the 2007 Infiniti G35 sport also taught us an important lesson. Though it might seem heresy to say so, not all sport sedans are better with a manual transmission.

Why We Bought It
We first saw the redesigned 2007 G35 at the 2006 New York Auto Show. Our intention to add one to the long-term fleet was decided on the spot. Upgraded materials were a step up from the plain but durable interior of the previous-generation G35. We were interested to see if the improved interior would still look good in the long run.

Nissan's 3.5-liter V6 has always impressed us. Some 80 percent of the pieces in this upgraded VQ-Series V6 were new for 2007, raising output to 306 horsepower and 268 pound-feet of torque. There was no chance we'd pass on the opportunity to put this new power plant to the test. The G35's platform had been carried over largely intact, but it had been tuned to meet a more demanding standard of sporting dynamics, and we wondered whether this athletic suspension calibration would influence the sedan's overall character.

Our full test of the 2007 Infiniti G35 with an automatic transmission revealed that the car performed better than many competing sport sedans we'd tested to date. If this truly was the new leader of the pack, we had to have one.

Durability
By far the most loathed feature of our long-term G35 sedan was the clutch, documented profusely on the long-term blog pages. Prior to this test, Inside Line would scoff at the notion that any automatic could be better than its manual counterpart. Not anymore. A manual transmission in the G sedan just doesn't work.

While the gearbox itself was up to the task, the clutch pedal was not. The senses we utilize to drive a standard transmission are simply confused by this car.

As a beginning driver, you learn to use engine pitch as a tool to anticipate the clutch engagement point. But from inside the Infiniti's serene cabin, its V6 growl was more of a purr. The combination of a stiff action for gas pedal and dramatically aggressive tip-in made throttle modulation more difficult than necessary. And the clutch pedal itself was far from delicate. Its pedal sweep was long, but the engagement point was short and abrupt. Together these elements simply disoriented the driver.

Engineering Editor Jason Kavanagh aptly wrote, "The clutch action conspires to ruin the driving experience by making the driver's every gearchange feel like the first he's ever done." We found ourselves seemingly left with two choices. We could spare the clutch and stall the engine. Or we could slip the clutch and abuse it as we engaged the transmission, keeping the engine running and maintaining our pride as we accelerated away from stoplights. We did our best to split the difference.

Inside Line Editor in Chief Scott Oldham had his own take on the subject. "This weekend I spent a day driving another G35 Sport with an auto box and was reminded just how fantastic the Infiniti is with two pedals. Then just yesterday I drove our long-termer and was reminded just how fantastic the Infiniti is with just two pedals."

Within its first 2,000 miles of life, the clutch pedal mechanism also began to creak. The sound is best described as a mixture of a Spanish galleon under sail and granny's old rocking chair. Both the downward and upward strokes of the pedal played the same song.

When driven hard, the G35 changed its tune. Chief Road Test Editor Chris Walton noted following track testing, "Balance on the edge of understeer/oversteer is exceptional. Unlike the BMW 3 Series, which feels unflappable and magnetized to the road, the G35 Sport feels lively and athletic. Almost as if it's on the balls of its feet. With that, a skilled driver can manipulate the car's ability to rotate with throttle application." These impressions ultimately fueled a luxury sport sedan comparison test. The G35 won.

Inside the G35's cabin we found luxury to match its driving prowess. After 20,000 miles, black leather upholstery on the seats showed little sign of the countless backsides passing across it. High-contact surfaces like the shifter, audio touchscreen and steering wheel proved similarly durable.

From a functional standpoint, we found the storage bins inadequate. There are too few and they are too small. The cupholders could also use some work, as the door-mounted slots don't accept larger bottles, and drinks in the console directly behind the shifter are asking to be spilled.

We experienced some mechanical issues with our G35 over the past 12 months. Each was resolved quickly by local dealerships, with the exception of the clutch. First to go was the cruise control. A blown fuse was to blame and was replaced easily by Cerritos Infiniti. The dealership was also the first to tackle the clutch pedal groan, and did so by slathering a layer of silicone over the pedal mechanism. This quieted the noise for at least several hours.

Our next scheduled service brought us to Fresno Infiniti. It had a different approach to the clutch noise. "That's normal," the advisor said. "There is nothing we can do." Reassured, we crossed them off our list of useful dealerships.

Fate brought us to Stokes Tire Pros in Santa Monica after a flat tire. A nail near the sidewall meant the $280 tire had to be replaced. In the waiting room we picked up the newspaper. An ad for Infiniti of Santa Monica was right there on top. We decided to try them next. And it was a good decision.

All remaining service went through Infiniti of Santa Monica. Our first visit was to replace a faulty key remote. It did so under warranty and informed us of an open campaign on the clutch slave cylinder. Parts took some time to arrive, but the service team scored points for keeping us well informed of the car's repair status along the way. Too bad the new slave cylinder didn't fix our original problem. We felt little improvement in clutch feel after the transplant, and the creaking remained.

Total Body Repair Costs: None
Total Routine Maintenance Costs (over 12 months): $236.76
Additional Maintenance Costs: $276.83 for a replacement tire
Warranty Repairs: Slave cylinder replaced, inoperable key fob replaced
Non-Warranty Repairs: $20 tire patch
Scheduled Dealer Visits: 3
Unscheduled Dealer Visits: 3
Days Out of Service: 2 days waiting for parts
Breakdowns Stranding Driver: None

Performance and Fuel Economy
Our 2007 Infiniti G35 aged well. All performance tests between its first one at 1,000 miles and its final one at over 20,000 showed improvement.

In the quarter-mile, the G picked up three-tenths of a second and broke the 14-second barrier with a run of 13.8 seconds at 102.3 mph. The G35 Sport needed just 5.5 seconds (5.2 seconds with 1 foot of rollout like on a drag strip) to reach 60 mph. From 60 mph to a stop, the 3,600-pound sedan needed a mere 109 feet, some 3 feet shorter than the result in its first performance test.

Dynamic tests also showed improvement over time. Slalom speed increased by more than 2 miles-per-hour to 69.5 mph. Lateral force generated around the skid pad grew to 0.90g. Chief Road Test Editor Chris Walton wrote, "It has an amazing ability to teeter on oversteer around the skid pad. Steering is a little heavy — springy, but offers a good deal of information. Tires appear to heat up quickly and limit results, however."

There was a mechanical price to be paid for the smoke-it-or-stall-it clutch. Walton noted following quarter-mile testing, "The G35's clutch spun on the first run all the way through 1st gear. There isn't much life left in it. But the engine still feels strong throughout the rev range. There are no dead spots."

Fuel economy over 20,268 miles averaged 20 mpg on premium fuel. Our highest and lowest recorded tanks were 26 mpg and 14 mpg, respectively.

Best Fuel Economy: 26.0 mpg
Worst Fuel Economy: 13.6 mpg
Average Fuel Economy: 19.5 mpg

Retained Value
Edmunds' TMV^® calculator valued our G35 Sport at $28,547 by the end of our one-year review. This equates to nearly 24 percent depreciation from the original MSRP of $37,400. This is on par with competitive vehicles in its segment.

True Market Value at service end: $28,547
Depreciation: $8,853 or nearly 24 percent of the original MSRP
Final Odometer Reading: 20,268

Summing Up
The 2007 G35 Sport offers some of the best value in its class. For $37K it provides performance on par with the best its competition has to offer. This car has the engine, brakes and suspension tuning to compete with the benchmark BMW 3 Series. It means business and should be taken seriously in the sport sedan world.

But though the car represents great value, a few things are lost in translation. While the cabin offers the restrained luxury we expect in a sport sedan, it's not as sensuously plush as some of the German competition. The interior materials proved durable enough to last, however.

When it comes to the transmission choice in the Infiniti G35, get an automatic. This G35 and a manual tranny are not a good match. Too many elements of the driving experience are muddled in the process of shifting with the stick. While the manual is supposed to make a sport sedan more like a sports car, it produces in this case something that's more like a truck. Rumor has it the 2008 model year will address the noisy clutch issue, but that is yet to be determined.

Play it safe and spend the extra $1,000 for an auto. Performance will still be impressive, we promise. Besides, it will cost more than a grand to buy a new clutch every 20,000 miles.

The manufacturer provided Edmunds this vehicle for the purposes of evaluation.