The Magnuson-Moss Act of 1975 prohibits manufacturers from specifying their own specific brand of fluids, filters, etc. to maintain a vehicle's warranty eligibility unless that manufacturer agrees to provide said items free of charge to the vehicle owner. In other words, Nissan can't deny a warranty claim on, let's say, a transmission failure, due to someone not using genuine Nissan ATF as long as the aftermarket ATF meets the manufacturer's specifications. They, meaning Nissan, would have to prove beyond any doubt that a failure is caused by using the aftermarket part or fluid in order to deny a claim, which usually means expensive legal costs more than it would be to just repair the item. Most reputable aftermarket parts companies will supply legal representation in such a case to the consumer because it's their product and reputation at stake. Now that said, I can understand why someone would want to stick with the manufacturer's branded parts because they don't want to chance going through all of that potential hassle!
I'm a former Nissan Master Technician and worked as a Nissan tech for a total of 16 years between 1986 and 2003. I've seen what poor quality parts can do, everything from misfiring non-NGK spark plugs to poor fitting air filters that allowed dirt to get around their poor fitting gasket. I currently have a 2006 Pathfinder, 2003 Frontier and a 1986 Sentra. I've had another B11 Sentra, a 240Z and a 260Z and a 97 Hardbody. I'm as particular with my parts as anybody! If it's not genuine Nissan, in most cases, it has to be an OE supplier to Nissan, i.e. Hitachi, NGK, Akebono, Bando, etc. Automatic transmission fluid standards in the US were pretty sub-par for a lot of years; I'm pretty sure there was no API standard for them for most of those years and I'm still not sure there is. Some years ago, the Japanese set standards on the automatic transmissions fluids for their vehicles (ILSAC has been stepping it up, as late, as well). Japanese vehicles have to meet the JAS0 A1 standard for transmission fluid, which is also the standard that applies to the Nissan 5-spd. and Infiniti 7-spd. automatic rear and four-wheel drive, automatic transmissions. Most of your synthetics will meet or exceed that specification. Castrol makes no less than eight types of automatic transmission fluids for various applications (plus one for CVT's). Reputable companies like Castrol, Valvoline, AMSOIL and Royal Purple stake their business on their reputation and if they state one of their products is recommended for an application (such as for Nissan-Matic Type "S" ATF), you can be usually be assured that it is.
I'm not going to put anybody down for using Nissan-Matic ATF. It's what came in the vehicle and you know that it'll work without any headaches. I have to admit it took a lot of research, convincing and faith before I started using Valvoline Maxlife ATF in my R51 Pathfinders, but I'm happy I did. I still remember the sight of a less-than-a-year old 350Z coming into the Nissan dealer where I worked on a flatbed with a bad torque converter because a quickie-lube place service the automatic transmission with Dexron III ATF. The quickie-lube company paid for the replacement of the transmission, but nobody wants to go through all of that!
I'm also a moderator at TheNissanPath.com, which sees a lot of posts from R51 owners. There are a lot of R51 Pathfinder owners that have switched to Valvoline Maxlife ATF; a few more have switched to Castrol Transmax Import Multi-vehicle, Royal Purple and AMSOIL synthetic ATF. I have yet to see anyone post that they've had issues with any of those aftermarket alternatives, which is a good thing. I wouldn't just dump any ATF that state's it's okay for Nissan "J" or "S" applications, but have no problem using one from a reputable and established brand, such as those mentioned. I've also found that Maxlife ATF works great in Type "D" and other, Dexron/Dexron II applications that are commonly used in older Asian vehicles, as well as the Mazda 5-spd. AT that specifies Mazda V ATF, used in the Mazda6 and Ford Fusions.
Now, on my 2006 and 2008 Pathfinder's maintenance schedule, there is no mention of ATF servicing under the "normal" schedule, only ATF "inspections." Basically, that means make sure it's full and service if the fluid is dirty. Synthetic ATF can last well over 100,000 miles under normal driving conditions and most people don't operate their vehicles under what Nissan refers to as "severe duty," which would mean a vehicle that is driven often while towing a heavy load or in extreme conditions where there is a lot of dirt, water, etc. Looking at the 2013 maintenance schedule:
...Nissan only mentions replacing the ATF at 30,000 miles as part of their "Optional Premium Upgrade" to their service schedules 1 & 2, or, if what is typically described as "severe duty," heavy towing, pulling a camper, car top carrier and/or rough/muddy roads.
If you continue through the guide, you'll see it only mentions "inspect" ATF all the way until the end at 120,000 miles, except for those conditions mentioned earlier, severe duty or as a "premium upgrade." I have no issue with someone who wants to do a drain and fill every 30,000 miles. I've done it myself, but it was easy when I had a full shop with a lift at my disposal. I've lost access to the shop, so I might extend it to 50,000-60,000 miles, now. I do like the fact that the ATF drains "red" now, instead of dark brown, after a few services with the Valvoline Maxlife. The "brown" color doesn't seem to be so much of a problem as more of a characteristic of the Nissan-matic "J" ATF. It's a very dark red color when new, so maybe that's why it looks sorta brown when it's drained?
As far as the next generation of the Frontier, it has already been released in other countries, like Mexico, as the Navara NP300:
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