Lemon ?

I have a QX4 that I have taken to the dealer 5 times for the same problem. .when I 'm traveling on the fwy, the car starts vibrating from 60-70 mph. below 60 and above 70 it runs normal. the dealer 1st said I need to balance the tire. Then they changed the drive shaft, then wheel bearings, now they are telling me I have to purchase four new tires because the threads on the tires are worn but the tire shop tells me that I still have good 10K miles life on the tires. Also just today the dealer told me that they found a bulitin from infinity saying all QX4s have this problem with the tires been slightly worn. Can someone please help me out? do I have a lemon and can I still qualify for Lemon law being only 300 miles below my mfg. warantee?

I have four Infiniti cars including a QX4 and not once have I ever had any serious problems with one. The QX4 is known to need wheel alignments more than some other Infiniti's (most SUV's do), but by no means do they have a problem with the tires wearing faster than any other car, unless of course your wheel alignment is way off. Certain tires don't ride as well as other so if you are using the stock Bridgestone Dueler tires, that could be part of the problem. The Bridgestone's ride a lot rougher than other brands. I'd try a Michelin MXV or Cooper Dueler A/T or H/T instead.

I'm actually shocked the Infiniti dealer changed your drive shaft and wheel bearings because both of these parts rarely wear out and when they do, its quite obvious as they'll make noise at almost any speed. Wheel bearings are especially easy to hear when they have gone bad (they'll make sort of a low pitched humming sound that sounds like grinding). The drive shaft generally won't vibrate unless the U joints are worn or its gone out of balance which isn't common on such a new car.

Do you know if your brake rotors are severely warped or if any of your wheels are bent? If so this could cause excessive vibration and pulsation. You may want to check them to make sure they are true and round. Also, no amount of balancing will fix a bent wheel so take them to a wheel shop and make sure they aren't bent.

I'm not sure what else could be wrong with your QX4 but I doubt its anything major as Infiniti is generally really reliable and well built. You may want to go to an independent mechanic and have him check your QX4 over to see what he determines, then go back to the Infiniti dealer with the mechanics findings and complain before your warranty expires.