Oil change interval recommendations?

[sc89]

I have a 98 pathfinder, live in canada where winter can be -20f and summer 80-100f. i drive mainly 75 miles to work, and 75 back. and once a week do a trip of 11 miles there, and then 11 back. i have 119,000 miles, owned the vehicle since 89,000 miles. i drive about 90% highway, with maybe a few stop and go's, such as stop lights and such, maybe 4 on each trip. since i had the vehicle, i have done 5000-6000 mile oil change intervals with a mobil 1 5w30 synthetic and mobil 1 filter. im not sure how much i can extend my oil interval, since going 10,000 miles seems a bit much as some people say on synthetics. im currently at 5,000 miles and considering the change. ok so with that information out of the way, anyone with good experience recommend i change the oil or let it go a few more thousand miles. the oil is pretty clean, definitely not dark..only a bit darker than the color it went in.

 

thanks so much in advance, any help would be appreciated!

 

oh yeah, any info on fuel filter change interval would be great, if anyone knows about that, i have been doing it once a year every year now, and i only do about 10,000 miles a year

[Towncivilian]

I would get a used oil analysis at your typical change interval (5-6k) and if wear and TBN (active additive left) still look OK, you can extend your interval. Of course, a UOA is around $25, so it may not be worth it for you since you can almost buy 5qt of M1 with that $25. I don't know how easy the VG33 is on oil, but I've read the VQ35DE shears oil out of grade rather quickly, which is why I choose a thicker oil (M1 HM 10W-40). If you're going to use M1, use M1 HM 5W-30 since it's the same price and has a somewhat more robust additive pack (likely has more detergents since it's deemed "high mileage").

 

I change my fuel filter yearly as well, but I'm thinking that's a waste. I'll go 2 years this time. I'm currently using a NAPA Gold 3023 (which is a Wix 33023); next fuel filter will be Nissan OEM, and I'll cut open both and compare amount of filtering media. Although maybe 2 years is too long for my intentions, could just swap it at 1 year again just to compare them earlier.

Edited August 12, 2011 by Towncivilian

[180sx]

If you've been using full sysnthetic, I'd stick with what you're using. Unless the High Milage is also fully synthetic, you'll just add gunk to your engine. I also have the VG33. I change mine every 3-5K miles. My reason is I do a lot of city driving with it. And with the tight factory clearances of the VG engines (more than even the VQ) I prefer to keep it fresh. Your intervals sound good. You could wait a little longer this time, see when your oil gets dirty, and change it just before that mark. Although, personally, I'd never go past 5K miles for an oil change (even when I was using Royal Purple in my old RX-7, I never went past 7K, and that oil is 'supposedly' good for 15K).

 

Jose

[Towncivilian]

Every Mobil 1 variant is synthetic.

 

Looking at oil color is a rather lousy way of determining oil's health/condition. If it's dark, it's probably cleaning a bunch of crud out of the engine, and it doesn't mean its additives are used up just yet.

 

Basically, if in doubt, change it out. Even if you waste a little money by changing it early, it's much better than changing it too late.

[sc89]

i think i will stick with the 5-6000 mile interval. my trip is mainly highway like i said, and i only run into traffic for about a few miles. i just want my truck to last, since i don't want to buy another vehicle anytime in the near future, so im trying to find ways to extend drivetrain etc. recently purchased filter mag magnets for my engine oil filter, and transmission pan, so hopefully that can help as well. don't want to overdo it and waste money, but i don't mind spending money if its going to make a difference. in last 10,000 miles i also changed my transmission, power steering, front/rear differential and transfer case fluid. fuel filter was done about 1000 miles ago, and oil change is next! also changed spark plugs, sparj plug wires, distributor, rotor (thing under distributor), battery (for one with 800 cold crank amps) in the last 10,000 miles. thanks for the useful advice guys, I really appreciate it. as mentioned, 5-6000 mile interval it is, sounds great

[Towncivilian]

What's the OEM rating for CCA? More is not always better - read this entire thread.

 

Change the in-cabin air filter behind the glove box or install one if none is present, it's an oft-forgotten item. Also brake fluid of course, and don't forget to grease your driveshaft.

[adamzan]

Mobil1 for 25 dollars? It is 56.99 for a 4.4 liter jug here!!