Hi, I'm new to this board.

I just purchased an 04 SL for my wife and we both really like this car. I find the recomended 3750 mile oil change strange, however. My 02 VW GTI calls for 10K oil changes (although I perform them at 5K). My son's Acura calls for 7.5K intervals, and my father's Accord specifies 10K changes.
Some BMW's now call for annual oil changes only (with synthetic). What's with the 3750. Seems a little behind the times.

 

I change my oil every 2,500 miles for the first 5 years then after that the interval is every 3,000 miles. I buy my own filter and oil that is why I can afford to change the oil every 2 months.

 

Just a rule of thumb for me, if I use dino oil, I change it every 3k, if it is Mobil 1, about every 5k. I could care less about what the scheduled MX says. If the oil looks dirty, time to change it. Doing an oil change is pretty easy yourself, preventitive mx, even if you pay someone like Walmart to do it besides the dealer, still pretty cheap. Alot of newer cars say they can go 100K without a spark plug change.....after owning my share of cars from BMW to you name it, I have seen plugs...especially platinum tips fail. My rule of thumb, if you plan on keeping the car, be **** about the maintenance. But than again, I am one of those people who take care of my stuff, anything from my electronics in the house to my car, I am a wash the car myself kind of guy and enjoy doing it. Just my 2 cents.

 

Nissans only hold about 4 quarts of oil whereas BMWs usually hold about 6 or more depending on the engine. But honestly no BMW or Volkswagon should ever be run to those recommended intervals even on synthetic oil. At the shop where I work we recommmend a 5k interval with synthetic and 3k with dino oil and we only service German vehicles (and Volvo). Maybe if more people actually got to see the attrocities they're commiting by running oil for such long periods of time they would understand why it's wrong to do it.

 

One more thing to add is that the German cars have huge oil filters compared to our Nissan cars. It's funny, if you look at the G35/350Z filter, it is even smaller.

I change the oil on our VW Jetta (don't laugh, it's my sisters), and after their recommeded intervals and I would not ever let them run that long again. With synthetic you can go a bit longer than 3750. I usually go till about 3000-3500 just because I'm a little **** about oil. With all of the cars I own, none of them have ever had a mechanical breakdown of any kind.

Luck has something to do with it, but so do the frequent oil changes.

 

The problem is not the oil. The lubricating qualities of dino oil are probably good for 30K. Over 100K if synthetic.

But the oil has TWO jobs: 1 - lubricate, and 2 - hold engine-harming impurities in suspension. By running the oil longer, the possibly harmful impurities (grit, blowby stuff, etc) stay in the engine longer.

If doing normal highway driving, I follow the 3750 mile interval Nissan reccomends. If driving on dusty roads or pulling a trailer, I drop that to around 2500 to 3000 miles.

The 'ability' of various cars to get more mileage between oil changes is fairly equal. Longer change intervals have pretty much the same impact on every make.

Most cars, like dogs, can survive considerable abuse and neglect. I choose to care for my Maxima and my dog. They are both better for it.

 

Appreciate the feedback. I personally use synthetic and change the oil at 5K (I change my own oil), but I believe I am being **** in doing so. I have read many of the studies (I am a Chemical Engineer by degree) and believe that modern dino oil can go 5K and that synthetic can go much longer. Having said that, I do wish Nissan would increase the oil capacity.

 

I agree with the points made by lightonthehill above. I ran conventional motor oil (called dino oil here) for 7,000 miles (one oil change) and switched to Mobil 1. I now go 7,500 miles between changes (this interval is acceptable in the owners' manual). As mentioned elsewhere on this thread, if you pull a trailer or operate in dusty conditions, change more frequently.

One motor oil contaminant that no one on this thread has mentioned is sulfur. The sulfur in gasoline combines with water from combustion (a gallon of gasoline produces almost a gallon of water when burned) to form sulfuric acid. Some of this sulfuric acid ends up in your motor oil. (The balance can end up in your muffler if you only do short trips.) This is particularly true when you driving calls for many short trips and the engine does not get hot enough to evaporate the water. The motor oil to be effective must neutralize this acid. At some point this neutralizing ability is overwhelmed.

In the days of leaded gasoline there was more sulfur in gasoline than there is in today's unleaded gasoline. I believe that the old (leaded gasoline days) rule of changing oil every 3,000 miles is outdated given today's lower sulfur content in gasoline. This is why I go the the maximum Nissan-acceptable mileage (7,500) before I do my oil changes. If I were only doing short trips or operating in a dusty environment, I would shorten this interval.

The goverment will in a year or so be mandating even lower sulfur content in unleaded gasoline. When this new low-sulfur gasoline is available, you should be able to go even longer between oil changes if you don't operate in a dusty environment.

The fuels and lubricants section of this site recommends waiting until at least 10,000 miles before switching to synthetic motor oil. Had I seen that recommendation before I made the change, I would have done one more conventional oil change before swithcing. Check out that area of this site for other recommendations including filters and brands of dino oil and synthetic motor oil.

 

I just changed my oil (Amsoil 5w-30) at 7500 miles and I did a filter change midway. The blackness of the oil that came out is enough to convince to me never do this again even with the best lubricants available.

The replacement oil I used was Mobil 1 0w-20 as an experiement.

 

Weird, my motor oil (2K Maxima SE) will get black literally as soon as I change it. Where as my father 2003 Grand Marquis at 6000 miles, the oil looks new. And this after coming back from a 1200 mile trip.

I don't think the blackness of the oil in our engines determines it's true dirtiness if that makes sense.

 

I work on cars for a living and changing engine fluids is part of that. So on a daily basis I get to see the difference between a well maintained car and a poorly maintained car. And I am pretty good at inspecting the oil as it comes out.

 

Is this true? I didn't see that in my manual. I was going to switch to Mobil1 at 10k and change every 5k to make it as easy as possible to keep track. But if Nissan accepts 7500, maybe I'll wait to 1500 for the changeover. Then I can rotate ties and change oil at the same time. How much easier can it get?

 

In the last paragraph of his informative post above, SilverMax_04 mentioned that the fuels and lubricants section of this site recommends using dino oil the first ten thousand miles. I am very glad he brought that up.

I remember this topic discussed at length here last year, and there was a poster who had contact with someone (IIRC) in technical operations with Nissan. He said synthetic oil prevents the motor from its normal 'seating and fitting' process, which is important to good engine performance and life. His recommendation was using dino the first twenty thousand miles.

I personally have been using dino oil the first 60 to 70K, then synthetic. I put over 206K on one Maxima engine, which was running very nicely when I let the car go.

I would urge that no poster put synthetic oil in a vehicle the first 10K. I feel 20K would be even better. Just my humble opinion.

 

aw man, I was ready and waiting for 10k. guess I'll wait for 20k. I'm still wondering about Nissan stating in print "synthetic oil change intervals every 7500 miles is exceptable."

Oh yeah, what does "IIRC" mean?

 

Maxima80 -
IIRC - If I recall correctly (I usually don't)
OTOH - On the other hand (hedging my bet)
IMHO - In my humble opinion (I don't use this; I'm not the humble type)
FWIW - For what its worth (usually not very much)
ILMM - I love my Maxima (OK, I made this one up)

 

I agree. It makes sense to me. If you want to know about your engine oil, you need to send it in for a lab analysis. How it looks does not mean very much, it is the chemical properties it still retains that count. For more on getting an appropriate lab analysis, check the fuels and lubricants section of this site.

On another issue raised earlier by me, I guess I mis-spoke. The information I used to determine that 7,500 miles was an acceptable oil-change interval for Nissan can be found on page 7 of your "Service and Maintenance Guide." That page shows three maintenance schedules with a guide for picking which one you should use. I selected "Schedule 2" (7,500 miles) because I do very little driving that this guide says requires Schedule 1 (3,750 miles) maintenance. The Guide lists the following as requiring Schedule 1:
- Repeated short trips of 5 miles or less in normal temperatures or less than 10 miles in freezing temps.
- Stop-and-go traffic in hot weather or low-speed driving for long distances.
- Driving in dusty conditions or on rough, muddy, or salt-spread roads.
- Towing a trailer, or using a camper or car-top carrier.

This 7,500 miles recommendation is not dependent on using synthetic motor oil. And if you consistently do any of the types of driving listed above, I'd certainly stay at 3,750 mile intervals. But I figured that synthetic (which will keep its good lubricating properties long after 7,500 miles) would just be the icing on the cake to make 7,500 miles appropriate for me -- given the type of driving I do. If this distance bothers you, simply send a motor oil analysis lab a sample of the oil you drain after 3,750 miles to see how much life it still has remaining. I'm not worried enough to do that, but if you discard synthetic after such a short distance (3,750 miles), the cost of this analysis may be worth it and could save you money in the future.