Another Synthetic Oil Question!

[grimm2420]

I posted like last month when i asked about getting a new sierra 2500 or 1500 crew cab. Well i ended up getting an Onyx black sierra 2500 LD 4x4 Crew cab with the slt trim and i love it. This is my first truck and i wanted to switch to synthetic oil ASAP. i live in southern California LA - Orange county area and want to use Mobil 1. What should i use (10w30 5w30) and is it safe to switch to synthetic right away? i have 1300 miles so far. Great forum by the way!

[XTOAK]

I bought mine two weeks ago and as soon as I got it home I switched it to Mobil 1 5W30. My experience has always been it's never too soon to switch to synthetic. You might hear otherwise from your dealer or others, but I don't believe you can go wrong switching as soon as possible.

 

(You might also do a search at this has been discussed several times on this board, and there are those who are one heck of alot more qualified to give this opinion than me.)

[grimm2420]

Excellent , but what should i use in southern cali, 5w30 or 10w30??

[Machine]

Either one. The 5W-30 flows better in colder climates while the 10W-30 works well in warmer climates. Regardless, it's the 30 grade that offers protection @ operating temperatures.

 

I live in S. Texas and run 5W-30 in my SUV's.

[o4yukonxl]

I did some research on this and unless you live in Mojave, you'll want to use 5W-30. I switched at 1300 miles to Mobile 1. A lot of the expensive cars come from the factory with Synthetic so you can't go wrong.

[Black02Silverado]

5W-30 Mobil 1 year round will work just fine. Some times you can get a great deal on it at Wal-Mart. At least here in the sticks of NC you can.

 

Switching over early at your mileage will not hurt a thing.

[99silveradoz71]

I run Mobil 1 5-30 in my 99 with no problems.

[JayMan]

For some reason I waited until 1,200 miles to switch, not sure why. At 600 miles I did my oil change to get the assembly crap out, but decided to run a cheap 5W-30 to flush it out more. One thing led to another, and at 1,200 I finally switched.

 

Due to my extreme cold climates, I run Mobil 1 0W-30 in winter. It cured the infamous "CSK" problem these motors have. Especially in temps colder than -10 F mine sounded like a diesel for the first 30-60 secs.

 

In summer I run Mobil 1 10W-30 as it has a slightly higher HTHS rating than 0W-30. FWIW the Helm shop manual suggests using a 10W-30 in warm climates or if working the motor eg towing. In your climate, why not run Mobil 1 10W-30 year round??

 

Folks at Bob Is The Oil Guy forum running LS-1 motors, which is what our truck Vortec motors are based on, claim oil consumption issues with the factory-recommended Mobil 1 5W-30. Most have substantially reduced their oil consumption running a synthetic 10W-40 or 5W-40 with no difference in fuel economy. I'm not sure what would happen if an engine warranty issue arose and they discovered you were running a heavier oil.

 

Since my truck is off warranty, I plan on using Mobil Delvac 1 5W-40 this summer, which is what my commercial equipment runs. Or I might use the new Mobil 1 Truck and SUV 5W-40 (Same as Delvac 1 but in quart bottles instead of gallon jugs) if available.

 

I've always used Delvac 1 in my previous personal vehicles with excellent results, and don't see why I can't in this motor.

 

Oh, another FWIW: in Australlia, the GM affiliate Holden runs LS-1 motors in several lines of cars and "utes" (Trucks). They recommend much heavier oil grades, like 10W-40 or 15W-40. Hmmm, makes you wonder as it's the same LS-1 used here in North America.

[SnakeEyeSS]

5W-30 seems so light to me now that I have my 325is. I run 15W-50, even in freezing temps here. although if I ever move north, I'll have to lower it for winter.

 

Run what GM says to, they put the info in the manual for a reason, every car needs different weights

[JayMan]

BMW still recommends a heavier viscosity grade, such as 0W-40, 10W-40, 15W-40, 15W-50, etc.

 

I just think it's very curious that Holden in Australlia uses GM LS-1 Vortec motors, the same exact motor used here in the Corvette.

 

Although Chevy recommends a 5W-30 or 10W-30 meeting GM 4718M specs, in Australlia Holden, a GM affiliate, recommends 10W-40, 15W-40, or 15W-50.

 

It's the same motor.

 

Sure, their temps can be a lot higher, especially in the Outback, but no worse than Yuma AZ or Death Valley CA.

 

I think a little common sense goes a long way. Now that my truck is off warranty, I'll try a 5W-40. If it doesn't affect fuel economy, and I bet it won't, then I'll use a heavier oil from now on.

[o4yukonxl]

I happen to also own a 2002 BMW 330i. Here is the oil recommendation for my car taken from the BMW web site.

 

Change oil and oil filter while engine is at operating temperature.

We recommend BMW High Performance 5W-30 Synthetic oil, p/n 07 51 0 017

 

These engines see 6500-6800 rpm, way more than any stock GM truck.

[superbee]

Much of the oil recommendation from manufacturers that sell in the US is driven by CAFE standards. If the factory can squeeze an extra .1 mpg it helps their fleet average mpg. Some new cars are calling for 5w-20 for this specific reason. Use common sense. Synthetic is better but costs more. Use the weight that makes sense and doesn't conflict with the manual. My wife's 03 6.0L calls for 10w-30 or 5w-30, in the winter I am using Amsoil Series 2000 0w-30. If you are really interested you can getperformance information from the oil manufacturers on their web sites, Pour Point, Flash point, ASME 4 Balls wear test scar size, etc. The CAFE thing is a possibility for the difference in reccommended weights between the US and Down Under.

 

 

Superbee

[JayMan]

I happen to also own a 2002 BMW 330i. Here is the oil recommendation for my car taken from the BMW web site.

 

Change oil and oil filter while engine is at operating temperature.

We recommend BMW High Performance 5W-30 Synthetic oil, p/n 07 51 0 017

 

These engines see 6500-6800 rpm, way more than any stock GM truck.

The BMW 5W-30 meets European ACEA oil specifications. Most BMW high performance cars and SUV's require a 0W-40 oil meeting ACEA A3, A5, B4-02 and BMW LL-01 specification.

 

A friend of mine in Salt Lake City has a 2003 X5 V8 and runs the 0W-40 year round. In hard use and particularly Rally events, they recommend a 15W-50.

 

Although Mobil has stopped publishing their detailed specs (CCS, MRV, etc) other oil companies can and do publish detailed specs. Though I'm unsure why you would want to know the 4-ball wear as that is for gear oil tests.

 

The HTHS for many xW-30's is borderline what the SAE J300 recommends for HTHS mins.

 

It seems that the bogus CAFE requirements are pushing makers to specify oils that help their fleet average, so even 0.15 MPG more applied over hundreds of thousands of units will add up. Once you're off warranty, you're on your own.

 

What I find interesting is the clear conflict between North American oil recommendations and the recommendations in other countries. Here in North America you see a very wide range of ambient temps: -40 to +120. It's nonsense that one grade of oil can meet such a wide range of temps.

 

Even when the same exact motor is involved, there are far different recommendations for other countries. As an example:

 

Although Honda recommends a 5W-20 or 0W-20 for North America, the same exact motor recommends a 10W-30 in Australlia and a 5W-40 in the UK.

 

I live in a climate that , so far this winter, has dipped to -43 F. In summer it can get to 95 F. To cover such a wide range of temps, I run Mobil 1 0W-30 in winter, since it's safe to -58 F. In summer I run Mobil 1 10W-30, although I will be switching to Mobil Delvac 1 5W-40 starting this summer, only for summer use.

 

I have found in ambient temps higher than 50 F, my Vortec makes a LOT of valvetrain noise at operating temp. A LOT of ticktickticktick that is substantially reduced with 10W-30.

 

A friend of mine in St George Utah has a 2001 GMC Sierra. He has run Mobil Delvac 1 5W-40 year round down there with excellent results. He changes the oil once a year and averages 1 quart every 9,500 miles. The motor is almost silent.

 

Some folks have argued the "engineer knows best." Most often, the engineer has his/her hands tied and must toe the corporate line. They can't recommend what is truly best from a long-life point of view, but must project an image of "maintenance free" and "CAFE compliance."

 

If you have any engineer friends, ask them about work. Whether in the electrical industry, chemicals, manufacturing, etc, ask them if they can do what is RIGHT or if they have to toe the line. If they're honest, they'll tell you they can do sweet F.A. with their servicing schedules, as those are set by beancounters.

 

I have an engineer friend who was forced to dramatically cut back oil servicing on giant tank farm agitator gearboxes. He even had to cut the bearing greasing interval on giant multi-stage centrifugal blowers running at 3,600 RPM driven by 500 HP motors. He warned and put in writing the expected early failures, which the bean counter acknowledged and then ignored.

 

As expected, several of the $480,000 agitator gearboxes had early failures and seized up. As expected, a couple of the centrifugal blowers had bearings seize up and they failed in a spectacular way. Yet the bean counter INSISTS they're saving money armfulls of money.

 

My engineer friend has figured that running synthetics at the "normal" vendor-specified service schedule, it would take around 385 years to equal the replacement cost of an agitator gearbox. The bean counter "savings" don't exist and so far have cost several million dollars in lost productivity and ruined equipment. Sort of like Enron Accounting.

 

So in the end you have to use common sense. Especially under warranty, use what the maker is forced to recommend.

[RyanZ71]

Why not just ask what weight of oil did the folks whos trucks have 200,000+ miles on the orig engine use? In most cases it's 10W30 and 5W30. Just stick to what has worked for folks for many years now.

[JayMan]

I think you have to keep in mind the driving the motor is put under.

 

Say it spends all its life in a "moderate" climate on the Interstate at a constant 65-75 MPH, no stop-n-go, especially no extreme cold stop-n-go. Unless that motor came with a defect, the cheapest Parts R Us Brand X 5W-30 would probably allow fairly good motor life of +200,000 miles.

 

Say you're working the motor at close to rated GVWR, towing or hauling in mountain grades. That Parts R Us oil will break down fast.

 

The absolute worst scenario is colder than 0 F in stop-n-go. You will experience heavy sludge as the excess condensation will cause a regular 5W-30 to fall apart: the polymeric additives drop out under such use.

 

The +1999 truck Vortec motors appear to be based on the high performance LS1 motor. Folks at www.bobistheoilguy.com - a site devoted to maniac oil nuts - report that running a 5W-30 in their applications has caused increased wear and oil consumption, like 1 quart every 800 miles.

 

Some of those folks refer to the LS1 and our truck Vortec as an "oil guzzler."

 

In many cases, those folks were able to substantially reduce or even eliminate their oil consumption, and get MUCH better UOA wear numbers, by switching to a synthetic 10W-40, 5W-40, or 15W-50.

 

They have also reported good results running a HD diesel motor oil 15W-40. They have found that the earlier they switch to a heavier grade for summer or heavy use, the better.

 

In my area, I was one of the first commercial users to switch from a regular diesel 15W-40 to Mobil Delvac 1 5W-40: average fuel consumption decrease of 2-3%, average oil consumption decrease of 50%, average extended oil drain based on UOA of +300%.

 

So again, use common sense. I've always run heavier oils in summer in all my personal cars/trucks with excellent results. If you swear by a regular 5W-30 or 10W-30, use it.

 

In the end, it's your money and your truck. Since I only allow myself to buy a new one every 10 years, I expect to get +300,000 miles out of it. So far, I can do this no problem following my service regime.