Best oil grade?

[MakDiesel]

It's just about oil change time (or flush the abuse out from the previous owner time) on my ZX and was wondering (since I've owned my car 4 months and some of you are tackin' decades) what grade oil to use now that I'm done using the cheap stuff for normal new purchase routine maintenance checklists (plugs, filters, rotor, oil change(s), etc) Here are my details:

Car: '81 280zx GL 5-speed non-turbo

Engine: L28E FI

Mileage: 177K original (no rebuild...yet)

Location: Central NC (summer weather ranges 70-95 degrees F)

Driving style: Shift between 2400-3000 RPM (I'm easy on my old motor)

Desire: a reliable daily driver (good mpg, decent performance, and most of all, longevity)

The only reason I'm asking is cuz I've heard everything from use Castrol 30W to mobil 1 synthetic (and watch my car blow that $5/qt. brown liquid out all the seals) not to mention my last vehicle was a truck so I call upon the vast knowledge of 3K worth of Z owners(and Z dreamers) alike. Thanx Peace

[dozer171]

i personally use valvoline 10W-40 along with the fram HP-1 (i believe it is 1) oil filter. that's the orange type of fram racing filters that doesn't have the grippy stuff on the end. most likely overkill (next step up would be a K&N filter for 10 bucks!). the purolator pure-one filters should be fine.

as far as weather goes, in rochester temps range from 80 - high 90's depending on the area's mood... last week it was 65 one day, snowed the next morning! gotta love it!

i have also heard using straight 30W oil is the best... ask 10 mechanics get 10 answers!

[antipodalboy]

Hey, don't use synthetics in your engine, you will lose it all. Now, this being said. I use castrol oils in all my cars. If you have the factory manual, there should be a reccomendation there for the oil weight to use. For summer, I generally use 10-40 in my cars (i don't have a Z yet so don't take it as gospel) and 20-50 in my truck.

[TKR514]

ANY brand of natural 10-30W, cheapest is fine. If it's well worn, bump up to a straight 30W.

It won't make a heck-of-a-lot-of difference after 20+ years. Just keep it clean and go for it would be my guess.

[Brett240]

dont use any oil's that have "for high performance, turbocharged engines" or anything like that. these oils are made for todays engines whcih have very tight tolerances. these oils are generally way too thin for a zed engine (mobil 1 i being 5w50 from memory) and can cause piston slap (from personal experience). a synthetic oil is the best choice AS LONG as its the right grade. i run 20w50 with a 1500 mile old engine, if youve got 100, 000+ miles a 20w60 is more the shot. most sraight 30W minerals oils dont have many (or any) additives and polymers in them to protect your engine so be careful what you by.

[dozer171]

i forgot to add this bit earlier..

you gotta remember, these motors are 25 years old. they were built long before synthetic or synthetic blends were even concieved of. also, the current API rating for oil is "SL". pretty much just meaning it's the latest and greatest. so, in other words, as long as the oil you buy has the API badge on it reading higher than SG, your motor is more than protected. the API badge just means it met the baseline for the oil, much like the ASE certifications for mechanics, not too hard to come by. different oils to have different additives though...

in high mileage engines, i like to use Valvoline Max-life. it has some additives that cause the seals to swell slightly to reduce oil leaks (front/rear mains, valve, sometimes the oil pan gasket, but rarely!) and consumption. i personally like this oil, as do many of my friends. however, this oil is ONLY for engines with 75K+ since their last rebuild, or, motors that have been sitting a long time and most likely have dry seals (like you just took it out of storage after MANY years and the oil consumption won't go down). if you use this on a newer motor, not good.. the seals can swell and warp causing a big mess, not nececerrilly threatening to the motor, providing that the oil doesn't leak out of the warped seals and doesn't choke off the oil supply to the valve guides...

so, again, 10 different guys, 10 different answers! :stupid:

[beandip]

:classic: I have been using Quaker State in my cars for over 30 years and have never had an engine problem, not a stuck lifter or anything . I use 10w 40 in my Z and every thing is good. I have gone into depth on research on the subject and getting into the different additives and ash content and so on. What I came up with is that Quaker State and GTX were rated the highest . Havaland , not spelled right , and then Valvoline. You will find that if you ask 20 people you will get 15 different openions. The most important thing is to change regularly and dont skimp on the filter and change it at the same time 3k is best. Cheepest insurence you can buy . I dident mention synthetics because I have never used them and see no need to change . I just returned from a 3K mile trip in our Camery and when I checked the oil it shocked me how clean it was , looked like I had just changed it , the engine has over 90,000 miles on it. its that clean. I was supprised to see that Kendal and some of the other more costly ones dident add up either.:classic: my 2 cts for what its wouth.