JohnnyZee78

Hi all,

I am new to the forum, and excited. This question may have already been posted, so apologies if I am wasting your time again.

I am trying to do an engine oil change. Confused as to what oil should I use.

I did some google search and it has confusing information. Some say Mobil 1 5-W-30 is the best oil to use but they don’t tell should it be synthetic or non synthetic?

Is it ok to put Synthetic oil ? They say synthetic is thin and May leak ?

also, what is the other type of oil other than synthetic ?

any advice will be greatly appreciated.

thanks

dmccain

iTrader: (2)

any of it is good as long as you are keeping the level checked and changing it every 3-4k miles 5w30, 10w30, 10w40... synthetic or conventional works just fine.

RedLeader289

iTrader: (2)

^yup^

navy02ws6

How many miles on the engine? Does it smoke it all? Any oil leaks? Internal engine problems? If it's less than 100K, and doesn't smoke or leak anything, then I'd say 10W-30. 10W-40 or 20W-50 if it leaks or smokes, and you don't plan on fixing leaks or rebuilding the engine.

I have probably 150K+ on the 305 in my '91 RS, it smokes occasionally on startup, and I have a nasty stuck lifter noise all the time. I run 3 qts of 20W-50 synthetic blend, and 2 qts of Lucas Oil Stabilizer, which helps quiet down the lifter noise.

JohnnyZee78

Thank you very much. Well I have 94k miles on the clock. Just got the car hence do not know much about it yet. I noticed it was smoking just a bit on startup but it could have been the cold weather (based in the UK).

So, when you say 10-w-30 do you mean synthetic ? Or partly synthetic. I have bought Castrol Edge 5W-30 (says on the bottle “fluid titanium technology, strong under pressure”). Possibly it is not synthetic ? Is it ok for my car ?

TransamGTA350

iTrader: (2)

Smoking a little on startup is worn valve seals. Common issue, not a big deal and has nothing to do with the condition of the rest of the motor. At under 100K miles, the motor is probably just fine and you can run factory spec viscosity oil.

The factory spec for oil viscosity is 5w30. You can use either conventional oil or synthetic. Synthetic is better oil, holds up to high heat better and can go longer between oil changes. But, conventional will still work fine as long as you change it every 5K miles or so. Synthetic can go 8-10K.

topduarte

iTrader: (8)

Google is your friend.

LAFireboyd

iTrader: (3)

Valvoline Max Life full synthetic, exclusively, since brand new.

Photographed this today just for this thread. My 2015 truck. A V6 that's as powerful as a 4thgen LT1. Still runs like brand new, gets better-than-new mpg, and the engine is still 100% factory original. It would've rolled over 400,000 by the end of 2022, but I spent October-March in Indy with my family, and I kept it in Dad's garage during poor weather and drove his car most of the time. Ironically, though, the winter in Indy was milder than out west this year.

Obviously, I recommend a high mileage oil, not just for high mileage vehicles, but for new ones too. High mileage oils were created specifically to combat the symptoms of aging in engines like the SBC, one of those being the reconditioning of worn valve seals, curing the puff of smoke at start-up. Use from new, and those issues aren't likely to develop.

Throughout the years, Max Life has gone from a conventional to a synthetic blend to a full synthetic, and it's always been my choice, but whichever brand you fancy..., synthetic or conventional, whatever suits your budget, in a weight that's suitable for your geographic region, which you didn't say.

5-30 tends to be the most recommended by manufacturers, due to its fuel efficiency, and because it's suitable for nearly all climates. 10-30 is just as versatile. You probably won't notice any difference between those two and 10-40 either, especially if you live in a mild to hot climate. And if you're in a climate like, say, Death Valley, then 10-40, even 20-50 will be good.

I've used Valvoline Max Life, exclusively, in all of my new cars and trucks since Max Life came out around the year 2000, when I began using it in my Formula. Over 300,000 miles on my previous truck that I had since new, then I gave it to a friend who still drives it. Over 200,000 miles on a previous car I had since new, before giving that one to another friend. I only buy new, and I put Max Life in them immediately.

JohnnyZee78

Thanks a lot for the wealth of information - super useful indeed. and wow !!! You have had great mileage out of the truck ! That’s awesome! Mine has done 94k miles.

I also probably did not mention, I am based in the UK (Scotland), and the weather extremes are between 17F to 90F max.

JohnnyZee78

Thanks, and indeed correct. The issue is google is throwing mixed and confusing discussions around this topic.

Tom 400 CFI

Good thing that forums don't do that!


As was stated in the first couple posts, any oil today, is way better than good enough.

Tom 400 CFI

It's already covered, but I wanted to add to this, based on data from my stuff, which aligns with LAFireboyd's post, above.

When "which oil" threads come up, I always say, "All oil today, is better then good enough". What's "Good enough"? The answer to that, comes from the question, "How long, is long enough?" In other words, how long does your engine really need to last? In some people's minds (my own mind, years ago, for example), we want our engine to last indefinitely, right? We don't need engine problems, so what oil will make my engine...."never wear out"? Of course, the rest of the car is going rust out, wear out, fall apart at some point anyway, so we really don't need our engine to last to infinity. So how long should it last? 150k? 200k? 300k? How long is long enough? I've settled on 200k for myself. By 200,000 miles, most cars that I've owned are in one of three categories:
1. The rest of the car is worn out/rusted out
2. I've lost interest and sold the car/got something else/car priorities changed.
3. The car has been relegated to "Toy" status, where it gets driven little, and has been modded to the point where the original engine doesn't matter or is no longer in service anyway (engine swapped).

Last night, I changed the oil on my 'Vette. One of the measures of engine health is oil consumption. The Oil Life Monitor called for a change, so I changed it and noted the mileage since the last change; 8100 miles, then I measured the amount of oil that I had drained out; 4.25 quarts. The engine burned .75 quart, over 8100 miles. That is some pretty low oil consumption, indicating pretty good engine health. Note that the engine exhibits good health in other measurable areas, too. Anyway, the car currently has 210,000 miles, gets daily'd in the summers and has seen a fair amount of drag track, road track and auto cross use/abuse. .75 qt over 8100 miles.

My very first car, an '83 Trans Am, w/the LG4, I drove that car to 200,000 miles, then sold it to a friend who drove it to 245,000 miles and sold it and I lost track of it. I ran "Cumberland Farms XP Lube" engine oil in it. Cumberland Farms is a New England, regional chain of gas stations/convenience stores. I don't think that their oil is exactly top shelf...but it was better than good enough. When I sold the car, it was faster than when I bought it, got the same gas mileage, started and ran perfect, and burned essentially, no oil between 3000 mile changes.

Another example; a '96 Silverado 1500. I ran the wee out of that truck, towed my boat to Lake Powell 100's of times, 620 mile round trip through mountainous terrain. No sports car I've had has been worked as hard as that truck was flogged with hours, upon hours of WOT use. 100's of hours at WOT, I'd guess. I had that truck for 15 years, sold with 300,000 miles, still running perfectly, by all measures. The body was rusting off the frame. How long, is long enough? For that truck, 300,000 miles was longer than the rest of the truck was good for, and the engine likely had another 100,000 miles of life left. Possibly more.

Finally, at work, I manage fleet maintenance on well over 100 vehicles. Been doing that for over 25 years, so with vehicle turn over and changing companies, I've been responsible for maintenance on over 1000 vehicles in my career. I've never seen an oil related engine failure. I've seen three engines fail at work;
1. Mercedes OM926 had a rod bolt unthread
2. Vortec 350 had an intake gasket failure, filled the oil pan with coolant and seized up
3. Early '80's Blazer, employee never checked engine oil, ran it out of oil, seized it up.

But more interesting, is the snow cats; one brand calls for a change interval of 250 hours -about two weeks' worth of operation. We change and sample at 250, as per the OEM recommendation on every cat. The oil samples consistently show that the oil isn't close to needing a change. All of the indicators; viscosity, fuel, metals, soot, cleanliness, etc....they all look fantastic and indicate that we could push out the interval significantly. Jackson Hole ski resort, runs the same cats and using sampling, they have pushed their oil change intervals out to 1500 hours -a full season! No issues. OEM recommends 250 hours. Oil is better than good enough. Way better.

So? Today's oil is pretty fantastic stuff, and when combined with a reasonable change interval, is way better than good enough...even cheapy-cheap, off brand oils do as well or better than we need them to. So buy the oil that comes in the container that you like the looks of...or has the brand that you like the sound of....or fits the budget that you have. ANY of 'em will do better than you need it to. Buy the right weight, change it on time, drive and enjoy..

TTOP350

iTrader: (8)

If you still have the original valve covers and oil fill cap, you may be able to read the recommended oil listed on the cap. (If it's not worn away)
and if you're lucky enough to still have the owners manual, its listed in there as well.

Roorancher

If you're going to use conventional oil, you probably want to use an additive like ZDDP, but usually that should only be necessary for flat tappet motors, which the 92 is not.
If the car has continually used conventional, id stick with it. Synthetic has been known ti increase the incidence of leaks of you switch over.

Tom 400 CFI

I think that's old, outdated "lore". My car doesn't leave a drop on the floor. Here is what my 210,000 mile car looked like when I slid under it last night. I took a pic, b/c I was, frankly, shocked at how clean, leak free it was for a DD'r.

Aaron R.

The old synthetic vs conventional and this weight vs that weight discussion/argument. Comes up in these forums every year. Some good advice from Tom 400 CFI and others in this thread though.

Im conducting an experiment on my 1985 305. I rebuilt that engine, changed oil after break-in and havent changed it since. Been about 13 years and around 50,000 miles so far on that oil. Stupid thing still wont burn any oil or wear out. Im afraid I might get several hundred thousand miles out of it....

Tom 400 CFI

LOL...keep us updated!

Fast355

iTrader: (2)

My 2011 4.0L Pathfinder has had Mobil One 5w30 since we bought it at 15K miles. It has had a trailer behind it roughly half the miles it has on it. It has a good bit more power, ~315 hp (Intake, Headers, Z1 Plenum spacer, Tune) than stock as well. Runs better than it did new. Still on the OE timing set as well even the secondary chain tensioner shoes.

My 2007 G35 Sedan 3.5HR has nearly 300K on it. Got it with 120K on it and have used whatever 5w30 synthetic was readily available. Mobil One or Pennzoil Platinum mainly. At ~230K I had to pull the valve covers to replace the hardened, brittle gaskets. It was near spotless under the covers.

The 4.7L in my 2003 Dakota that started life in my 2006 Ram was just as clean when I had to tear it apart after it broke a beehive valve spring. It was cammed and spun to 6,800 rpm often. It was Mobil One 5w30 exclusively.