Well I am going in for my first oil change. I bought the car used at 96K and I am now at 97K, and since I got no service records with the car I figured I might as well change the oil, better to be safe than sorry. Well I have two questions:

1. Since I got no service records I have no idea if the car is running on regular oil or synthetic oil, is there any way to tell which kind of oil the car is running on?

2. I bought some Mobile 1 Tri-Synthetic but have been told recently with the amount of KMs I have on my car (97k) switching to synthetic (assuming I have regular oil in there now), is bad for a car at this age. What do you think I should do, use regular oil or synthetic, is switching to synthetic at my mileage really bad?

- Steve

 

Many debates on this. I personally would do it. But to keep putting in conventional is a safe route from leaks and the car will still go 200k+ miles.

I think it would be safe to put in the Mobile, I would.

 

The typical Maxima owner is not gonna pay for synthetic oil, so chances are it's dino juice in the crankcase. The VQ mysteriously consumes oil as it is, the last thing a person would want is a rear/main seal problem--I would recommend regular oil. It gets so annoying for the dealer to tell you that all the issues are normal, it's only "blow-by" that collects on the block. WTF is blow-by, let's be real! If it's normal, it should have been designed so it wouldn't collect like that!

 

1. Since it's cold where you are, pull the dipstick tomorrow morning. If the oil is like molasses, it's dino. If it flows okay, it's synthetic.

2. 97k is not high mileage for a good VQ and switching to a synthetic shouldn't cause any problems, unless you already have leaks or the engine was neglected badly prior to you.

 

It's not Maxima-specific and there have been many complaints of leaking starting after switching to synth in higher mileage cars. It dates back to the 80's. Every motor is different, but it's because synth lacks mineral spirits which the seals are used to when it's been running conventional oil. Why waste the money on synth oil in an older car that's run its life on dino juice? 4-5k oil changes is gonna more than exceed requirements. No reason to add potential leaking to the list of problems imho.

 

Yep, poorly maintained higher mileage cars can be a problem. It IS Maxima specific though. If it were a Ford with 97k, I would be looking to sell it. The VQ is extremely durable and good for many more miles, so I don't think in the grand scheme of things that this particular motor is high mileage. It also does NOT have an oil consumption problem. Some of them use a little oil, big deal. A quart for every 3000K is not excessive, even though I know you think modern engines shouldn't burn any oil. We're squeezing more and more power out of a smaller displacement and running smaller sump capacities to boot, all of which places more and more stress on the oil. Why is it surprising that when we take a conventional oil and beat the hell out of it at 6500 rpm that it uses a little oil every now and then? If you want to see a true consumption problem, look at the SE-R's or the SVT Focii. They burn way more oil. Or better yet, an RX-7, it's not unusual for them to go through a quart every 700 miles.

The 80's?? Oil technology is so far advanced from that point the seal issues from back then aren't even relevant. For the record, the majority of the problem was the lack of organic compounds that promoted seal swell, which caused them to shrink a little and creating the leak. Modern synthetics do not have the same issue at all and the brands with the higher ester content can actually help recondition seals in some cases.

 

Not sure of the circumstances from which you bought the car, but as far as the service records this this is what I did. I went to the two closest Infiniti dealerships from the previous owner. Gave them the VIN # and they gave me all service records for my car. Now I know what has been replaced. A new starter, rear O2 sensor, knock sensor, and my tranny has had leaking problem at the drive axel seal for years. I know this is not a feasable thing for all to do, but you never know.