jzvette

Just alittle more background, I have an 89 coupe L98 with 140,000 miles?? I live in Pennsylvannia (northeast). What brand and grade would be best???

vette&f-bod lover

I run 10w30 for above 50k miles.mobil 1 filters are fine,tests show they trap more particles,clean better,than the stock delco.not overkill IMO.K&N's also a good 1.

jzvette

Is everyone out there using Mobil 1 5w30???

Golden80

I have 130,000 miles on my L98 and still run Mobil 1 5W30. Doesn't burn or leak a drop either.

mseven

I dont know about everyone, but a QUALITY synthentic is what its about. M1, Amsoil 2000/3000, has been great forever!!!
For fear of starting a debate here, I use M1 and syn. filter in my dd and amsoil 3000 and am.filter in my vette. I think 5/30 is a good all around weight, if I lived in a warmer overall climate, I would (and based on your mi.) bump up to the 10 /30 .IMO

jzvette

mseven,
Why bump up to 10/30, what is the benefit??? JZ

mseven

I just look at it as the temp. ranges by the mfg. at that point. The 5/30 is good to a lower temp.(below 0) rating and if it isnt needed I dont bother. In my exp. it has seemed as though the 5/30 thins quiker in hot weather (if memory serves me the 10/40 also has a bit higher heat range).

Try a search on oil comparisons, which should include temp. ranges, flashpoints etc.

jzvette

Can anyone explain the exact difference in oil viscosity and how would it affect me in Phila PA???? I thought the first nimber (ex 5 or 10) represents the cold weather viscosity of the oil and the 30 represents it's warm weather viscosity. Am I wrong??? Would using 10/30 be better on a high mileage engine in PA or is 5/30 just as good. It gets cold in Phila PA, but not that cold and I don't drive my car much in the winter. Does anyone know the truth??????? JZ

mseven

I didnt try to begin all the properties conncted to mlti weight oils, this would contain an extemely lengthy set of details, buy try this http:// www.nightrider.com/biketech/oilinfo1.htm

jzvette

mseven,
The link you listed didn't really answer any of the questions I asked.I will search the net for some answers, but I thought someone on the forum would know what is a good viscosity to run in an 89 L98 with 140,000 miles on it.(In PA) JZ

_twisted_

I'm in the same climate as you are: I use 5/30 until it stays above 50 degrees summertime 10/30. I dont think you'll find a 10/40 synt maybe 15/40. GM stopped using 10/40 and went to 10/30 in the 80's.

madmike

I run Mobile 1 10-40 with the sister (longer) K&N filter. I apply magnets to the filter to sweep for metal and I have 305,000 miles on my L-98.... Crank engine over for 10 seconds after oil change to pressurize and fill filter.

dan6712cc

I read that 5 and 10w are the same viscosity when they reach operating temperature.. unless youre doing short trips I dont see how it would matter that much.

Mr. Peabody

I think that you got got your answer.

BTW Philly is not a special environment. I spent many years in New England, Upstate New York, & West Chester PA. You don't need to go to a 5 weight, a 10 will suite you just fine.

rws.1

10W30 will be fine.
However, 5W30 is better.

Formula 1 and even NASCAR now use 0W30 motor oils.
The old school belief was that your needed higher film strength to promote good lubrication.
The new school says it is all about getting lubrication as quick as possible to all remote locations of the engine if you want to maximize engine life, horsepower and mileage.

Since 5W has a lower viscosity at temperature below 100 degrees C
(approx 210 degrees F) It gets the oil to those surfaces quicker until the engine gets into operating range. Once the engine is in operating range there is very little diference, BUT a 5W will still outflow a 10W until the oil temperature is 210 deg. F.( this is the temperature at which the 30 weight viscosity is measured and at this temperature and above, they will both perform identically)

JonLT4CE

Actually, M1 10-30 has a higher vis. at 100C than 5-30 does. That tells you that they have to use more polymers in the 5-30 to get the vis. change. That's why I use 10-30. Of course, I'm in Phoenix so I don't see anything approaching 0.

In general, the higher the viscosity range, the more polymers have to be added to get the range. These added polymers don't add to the sheer strength. Years ago, you never wanted to touch a regular dino oil that was 10-40. The add packs now help mitigate this but for the desert, I want the extra protection.

In Phili, you're fine with 5-30, GM knows what they are doing.

Fuzzy Dice

I don't get fancy...I put in what the owners manual calls for...Mobil 1..10-30...I have 110,000 miles on my 93 and drag race it a lot...

onedef92

I just changed mine with Mobil1 5W-30 and AC/Delco PF-52 filter.

dchildress

Finally A post right up my alley.... I own a couple of Valvoline Instant Oil Change shops and am a huge Vette fan. I have 77, a 94 LT1 6spd, and am in the middle of buying an 02 LS1 6spd with less than 22k.

Everybody shoud know this. Viscosity is the resistance to flow. The numbers, 0,5,10,15,20 W 20,30,40,50 and so on tell you what the viscosity rating is. The W stands for Winter and lets you know it is approved for winter conditions by the API , American Petroleum Institute. The first number tells you what the resistance to flow is at ambient, cold start temps, the second tells you what the resistance is at operating temps. SO....5W30 has a resistance of 5 when cold, 30 when at operating temps. Notice I say operating temps. Once you get above "normal" op temps like you would racing or even autocrossing is when the diffenence in oils starts to show.

If somebody wanted the best oil and wanted to compare themselves...I would start with the manufactures' website (aka Pennzoil, Valvoline, ...) and compare their MSDS sheets. These sheets will tell you flash points. In theory, a higher flash point is an indication of a lesser chance oil will break down under heat. A person in the know once told me, take the top 5 brands of oil, boil them down to nothing and analyze them you will find there is less than 2% difference in what they are made of. Same person said on a normal consumer basis, the customer will never notice a difference in brands of oil. Most conventional motor oil are made of the same thing called Base stock or pure base. The difference lies in the additive packages. Pennzoil makes a big deal..."made with PureBase" So what, so is everybody else. Next time you see a commercial for synthetic oil, listen to what they say "our oil is proven to outflow and outprotect any of the conventional oils and the market". Of course they can. Any brand of synthetics can outperform conventional oil.

I run Valvoline MaxLife full synthetic 5W30, year round. The additives have almost STOPPED the main seal leaks that plague my garage floor.


Many Fords, Chrysler, and Honda vehicles run 5W20. In Europe 5W40 was the norm, but now moving toward 0W20. To meet the needs of 0W20 and 5W20 oils you will find these to be basically a "synthetic" blend. It is hard to maintain shear ratings of these oils in "conventional" type oils. Why such thin oil? It takes less energy to move thinner oil. Look at the bigger picture, if 5w20 save on tenth of a gallon of gas and gives you one tenth of a horsepower it in theory saves thousands of gas a year. Engines are made with less tolerances than ever before, so a thinner oil is needed to "squeeze" into these smaller areas. I understand the lower visc oils have a lower burn off temp, as so to burn off and not clog converters.



I always tell my customers to go with what is on the oil cap or in the owner's manual. That motor was desinged around a specific grade and viscosity of oil, changing these things may damage the engine. On Ford vehicles with the 24 valve V-6 (Contours, Mazda MPV, Ford Escape and Mazda Tribute) the oil pump is designed for 5w20. If you run 20w50 in that motor, you will burn up the motor VERY quickly as the pump CANNOT pull the oil from the pan. A man came in to tell me only run what is on the cap on his new truck. On his 2002 F150 with the 4.6 V8, he only ran 15W40 Rotella. The oil pump could not pull the oil from the pan and he locked his motor up with less than 25K on it. After showing his oil change receipts to dealer, the dealer refused to cover the engine because he ran too "thick" an oil.



BOTTOM LINE......Run the viscosity your owner's manual calls for. If you plan to race, contact an engine builder for recs.


If interested about the ratings (GF-3, the new GF-4 oils or API Service categories...just email me).

jzvette

dchildress and everyone else,

Still no one has truly answered my question, maybe there is no answer. I have an 89 coupe, stock, some bolt on mods (K & N Air Filter, air foil, Power coupler, no pre cats (still has 3 stage main cat), 140,000 miles. IS IT BETTER FOR ME TO RUN MOBIL 1 5W30 or 10W30, can anyone answer this question?????? Owner's manual says run 5W30, some techs say run 10W30, WHY????? JZ