General Strategy for Prolonging Life of this great SUV

[mvmcali]

Ive had my 2001 QX4 for 15 years and 134k miles. I love this thing. I hope it lasts forever.

Any advice for preventative maintenance, etc for high milage older Qx4s?

How often are people changing fluids for example. it seems the manual suggests every 30k miles but not sure if that applies to front/rear diffs and the AT?

Also I dont put a lot of miles on mine. Ive put 20k miles on since the last major service and that was 3 years ago. should we really change fluids based on time as well as milage (or is that just a way for them to sell us more stuff)

[QX4ME]

I bought my 2002 QX4 new. Even when it was under warranty, I tried saving a bit money by skipping couple of routine services, or do intermediate level service when it should be major service. About 3 - 4 years ago, I had transmission fluid and propeller (?) fluid serviced. I change engine oil about every year with Mobile 1 most times regardless of how many miles I drive that year. No costly service anymore. It's got about 105k miles now and runs very well. I don't think it will die on me any time soon.

One time a shop found an O-ring seal slow leakage somewhere I don't remember. It was a few dollar part plus labor cost. The original retractable antenna stopped working and I replaced it myself. Except those, there has been absolutely no other issue.

[04pathse]

One time a shop found an O-ring seal slow leakage somewhere I don't remember. It was a few dollar part plus labor cost.

Most likely the oil cooler

[QX4ME]

You reminded me of that. Thanks.

[mvmcali]

yeah... my oil cooler went out several years ago too. luckily I took it for a 2nd opinion... the first shop saw oil on the front drive chain and thought it was a leaky seal on the 4wd. they would have taken the whole thing apart ! the 2nd shop realized that the oil from the cooler had simply dripped down on the other thing...

my antenna also went out. I had to take the whole wheel well apart to get to it. and then dissassemble the motor drive to replace the $20 plastic toothed drive... when i was all done... I had this large spring left over not my finest mechanical moment!

It would be good to hear from some high milage owners to see what maint they have done

[mvmcali]

yeah... my oil cooler went out several years ago too. luckily I took it for a 2nd opinion... the first shop saw oil on the front drive chain and thought it was a leaky seal on the 4wd. they would have taken the whole thing apart ! the 2nd shop realized that the oil from the cooler had simply dripped down on the other thing...

my antenna also went out. I had to take the whole wheel well apart to get to it. and then dissassemble the motor drive to replace the $20 plastic toothed drive... when i was all done... I had this large spring left over not my finest mechanical moment!

It would be good to hear from some high milage owners to see what maint they have done

[RR425]

I bought my 01 QX4 4.5 years ago with 95,000 miles. Now it has 155,000. Changed alternator, spark plugs, rear control arm bushings. Hope it lasts past 250,000.

[mvmcali]

did you notice any difference in how the car ran (or idled) after you changed the plugs?
I had mine changed at 110k and didnt notice anything.. was hoping that it would run a bit smoother
when I first bought the car (with 20k miles) you couldnt even tell that the engine was running!

[bryanmenard]

I have two QX4's: a 2001 with 240k miles and a 2003 with 188k miles, both in excellent working order.

My general strategy is follow the maintenance schedule in the manual and to fix issues as they come up. I don't let things linger on my vehicles. Fix LEAKS as they occur and, while you're in there, change anything you can to maximize your value on labor. The main seal is regarded by some people as being this awful job and it's not. Take it to a transmission shop - they pull transmissions all day - and have them do it. You'll find that, with proper equipment, your cost on that job - a job EVERY Pathfinder or QX4 will need at some point will be dramatically lower at a transmission shop. When you're done and the car is sealed up, you'll really find it to pay dividends in the "I feel like my car is worth keeping" state of mind.

For fluids, I monitor condition regularly visually. I use Mobil 1 5W30 High Mileage in both cars and I use Genuine Nissan fluids for everything, including coolant. I change the oil at 7500 miles and the other fluids I just monitor them visually and never exceed the factory schedule. I've done the differentials, transfer cases, and transmission fluids as needed. Nothing too rigorous. These cars are really well made and they are notorious for their ability to take unbelievable abuse. Doing even the minimum is fine on these.

Keep the rubber fresh. That means hoses, belts, seals, tires, all of that.

If you have a 4WD or AWD model, use the 4WD or AWD regularly. Don't leave it in 2WD for months on end. Run it in Auto or 4 High at least every so often. It's a SUV. Have an adventure now and then. For me, that's by necessity, but cars that have spent their whole life run in 2WD mode tend to have issues with 4WD when someone finally goes to engage it. Use it if you have it. I run both my QX4's in AUTO mode all of the time and only rarely use 2WD mode. I've never had an issue and my MPG is fine.

I recommend rustproofing and undercoating. I live near the Gulf of Mexico and it's never failed me on any of my cars. Wash off salt, sand, and dirt as it gets on the car. Don't wash or wax the car too often. Over washing and overwaxing will inevitably lead to swirl marks. Rinse regularly, wash and wax less. My cars both look beautiful and I wax them maybe once every 2 years and wash once a month but rinse regularly. ZERO swirl marks.

Interior care, use a sunshade on the windshield (I use custom-fitted Heatshield brand) and have window tint on the front two windows if it's legal. That goes a long way to keeping them in good shape. Garage keep them if you can. For keeping up the leather, I use Leatherique Leather Rejuvenator once a year and, between that, I use Leatherique Prestine Clean. Never failed me and my interiors look great.

[atraudes]

You can find a good maintenance schedule here. Like others have said, stay on top of maintenance and don't ignore leaks, smells, noises, smoke or dash lights.

[mvmcali]

wow... great summary . thanks!
so specifically with the AT... are you actually changing the fluid every 30k? i think that is what the manual says.
mine has probably been changed twice over 135k miles. Im wondering if it is worth 'dropping the pan' rather than just drain. the reason being to get out any sludge/metal bits in there.

has anybodys leather drivers seat started to rip at the seam? mine started that and Im wondering how i can patch it or something so that it doesnt continue.

[atraudes]

I do a drain and fill every 15k or so and also run a Magnefine filter. I don't mind the more frequent work as it's not much more difficult than an oil change. If you went with a longer interval you'd want to do a full flush instead.

Dropping the pan and cleaning the magnet and such probably isn't a bad idea every 100k or so. A Magnefine filter will keep the sparkly bits out of there though

[AlanAZ]

did you notice any difference in how the car ran (or idled) after you changed the plugs?
I had mine changed at 110k and didnt notice anything.. was hoping that it would run a bit smoother
when I first bought the car (with 20k miles) you couldnt even tell that the engine was running!

Changed mine at 130K, and saw a noticeable difference, both in smoothness and mid to high range power. The original plugs had the very tip of the electrode eroded down to the fat part, increasing the gap considerably. I did notice that it was difficult to get the torque on the new NGK PLFR5A-11 plugs right (compared to plugs in other cars -- I normally use a torque wrench on the first one or two, and can do the rest by duplicating the feel of the seat point, and then 1/2 of a turn), and had to carefully use an torque wrench on each plug, it was impossible to do without. I also did a through clean of the Throttle Body, since I had it off to do that one plug and proactively replace the IACV gasket.

I do recommend proactively replacing the IACV gasket. If/when it fails, it will lunch your IACV sensor, and possibly the ECM:

2001 Infiniti QX4 IACV and ECM question

[mvmcali]

hmm. i have no reason to doubt the shop that did my major maintenance at 116k but im wondering if they really replaced teh plugs. i had asked them to save the parts so i could see, when i picket up car, they said the mech forgot to save them, then the owner went looking in the trash for them. he pulled otu a plug and said it was one of mine. it didnt have that much wear on it as Id expect after 116k miles , also i didnt see any difference in the way the car ran.

I suppose I could replace them again myself this time only 20k miles later. it sounds like there is quite a bit of parts removal to access the plugs?

[AlanAZ]

Pull one, the dvr front is easiest, and post a couple of photos here, I can tell you if it looks like the new ones or old.

How to: Replace Pathfinder or QX4 Spark Plugs (VQ35DE engine)

[mvmcali]

thanks. i will do that.

[QX4ME]

I replaced spark plugs myself before 100k miles. None of the original ones looked bad. I can't tell any difference in performance before and after.

[bryanmenard]

wow... great summary . thanks!
so specifically with the AT... are you actually changing the fluid every 30k? i think that is what the manual says.
mine has probably been changed twice over 135k miles. Im wondering if it is worth 'dropping the pan' rather than just drain. the reason being to get out any sludge/metal bits in there.

has anybodys leather drivers seat started to rip at the seam? mine started that and Im wondering how i can patch it or something so that it doesnt continue.

Yes I change my transmission fluid and filter at 30k. I never do flushes of any kind. Drain and refill all fluids. The trans fluid at 30k looks new but I do it anyway. Both cars shift like silk.

My leather driver seat on my 2001 is torn at the seams and not repaired. My 2003 has no tears in the leather, probably because I've used Leatherique on it more diligently. I learned my lesson on the 2001 but I'm not dropping $700 to rebuild the seat and there is no generic Katzskin like kit for these rigs. On both cars, the passenger seats are all beautiful and like new. The 2003 is softer and more supple because it's had Leatherique its entire life.