How long before switching to Synthetic?

shelbyd · January 20, 2004

Hi All, I have 1500 miles on mine and am ready for the first oil change.

What is the rule of thumb for switching to Mobil 1? Is it to soon for me?

Thanks for the input.

Chevyfreek · January 20, 2004

You can switch to Mobil 1 synthetic at any time really. Some vehicles come with Mobil 1 from the factory. Synthetics are the way to go....

gmcjoe · January 20, 2004

I agree

Mobil 1

superbee · January 20, 2004

I switched to Amsoil 0w-30 at 1400 miles. Synthetic is definitely the best.

Superbee

pknowles · January 20, 2004

Not to soon at all. I love Mobil 1 tri-syn and use it in all my stuff.

PaulSter · January 20, 2004

Yup-- you can switch over at any time. No worries.

PaulS

JayMan · January 21, 2004

The idea of a "break-in" belongs in the past. Just to meet OBD2 emissions from new, most motors are put on dyno's at the engine plant, fired up, and broken in. Otherwise, you'd quickly contaminate the O2 sensors and cats.

I did my first oil change at 600 miles to get the crap out. I put in regular 5W-30 again just to help flush everything out good and at 1,200 miles switched to Mobil 1. I only wish I had switched to Mobil 1 sooner, but it was too hectic.

Due to my extreme cold winter temps, I run Mobil 1 0W-30 in winter. In summer I run Mobil 1 10W-30. FWIW I average about 4,200 miles per quart on 0W-30 and 6,600 miles per quart on 10W-30.

Am planning on switching to Mobil Delvac 1 5W-40 for summer. That's what I use in the commercial equipment and it's a VERY good motor oil, exceptional HTHS and beefy additive package.

THE BIGPUNN · January 21, 2004

i switched to mobile 1 synthetic at 2000 miles.

gmcjoe · January 21, 2004

The idea of a "break-in" belongs in the past. Just to meet OBD2 emissions from new, most motors are put on dyno's at the engine plant, fired up, and broken in.

??? What manuf does this?

JayMan · January 21, 2004

The idea of a "break-in" belongs in the past. Just to meet OBD2 emissions from new, most motors are put on dyno's at the engine plant, fired up, and broken in.

??? What manuf does this?

ALmost all of them. Ever been to an engine assembly plant? Though they claim to do this for "quality control reasons to ensure our customers are always satisfied."

Most of my family from my Dad's side is from Motor City (Detroit). A lot of them worked at various car and motor assembly plants, and all have entertaining horror stories. Especially from the "good 'ole days."

In many cases, the first time the motor was even fired up was when it was mated to the car. Sometimes, up to 5% of them would calf right there. Up until catalytic converters were required, this wasn't a big problem. The margins were also MUCH better back then.

Have you ever rebuilt a motor on your own? First time you fire it up, clouds of blue smoke. Ever thought what that might do to an O2 sensor or a cat? Me neither, since I've never rebuilt a "modern" engine.

BTW: most engine assembly plants are fully automated. The block honing process is done with CNC (Computerized Numerically Controlled) machines. Most parts are assembled using "pick and place." The only hard part was torquing the parts: torque measurement is derived from angular values, and the automated machinery needs CONSTANT calibration. A huge pain in the a**, with a LOT of possibility for errors.

That's why almost every new motor uses "torque angle" values. It's a no-brainer for an automated machine tool to sense angular rotation. This is a direct measurement that does NOT need calibration, so the CNC process is much faster too. Applied torque in lb-ft or whatever is DERIVED so you have to do math in the background, need to do a lot of calibration to known "standards" and is slower.

The Europeans makers (BMW, VW, Porsche, etc) started engine dyno "break in" a LONG time ago. They had entirely different reason to do so as they adopted emissions control a lot later than we did.

Think about it: you pick up your new Mercedes or BMW at the dealer in Munich. Very nice ride, very sophisticated. You get on the Autobahn and put the pedal TO THE MAT: 250 km/h or 155 MPH. Keep that pedal to the carpet all the way to Bremen or where ever you want to go.

If you took a raw or "green" motor and tried that, it would self destruct. Until the motor is "broken in" there is very high metal wear, and until the rings "seat" there is high oil consumption as well. With factory engine dyno break-in, many European cars run factory-fill synthetics. That would be impossible if the motor wasn't already good to go.

By contrast, we have been taught for generations to carefully "break in" the motor. You know, drive like a little Granny putt putt putt putt at 40 MPH or some nonsense like that. Don't "work" the motor, baby it. Yeesh. Maybe I should get out and PUSH IT for the first 5,000 miles??

The cylinder honing process is much better and MUCH more consistent now, thanks to CNC: there is a cross-hatch pattern on the cylinder. Rings are different too. That's why a do-it-yourself rebuild with 50 year old techniques is always poor results. I'd never rebuild another motor on my own but get a Crate Motor built the Modern Way.

A friend of mine picked up a crate LS1 motor from GMPP for his Chevelle. I copied the Motor Startup Guide and will quote from it:

"Prime oil system. Start engine and run at 2,500 RPM for 30 minutes. Shut off and change oil and filter, using 10W-30 oil."

"Drive at varying speed for first 30 miles, do not use WOT or heavy throttle. Then, run six medium-throttle passes to 5000 RPM, coasting off to 20 MPH after each pass."

"Run a couple of hard-throttle accelerations up to 5000 RPM, coasting off to 20 MPH after each pass."

"Change oil and filter again, using 10W-40 oil. Do not use synthetic at this time."

"Drive next 500 miles normally, try to avoid high RPM's, hard use, or high loads. Change the oil again, you may now use synthetic and drive as you wish."

One or two hours on the dyno would avoid all that break-in, though if I read the GMPP instructions correctly, at 500 miles you're good to go.

My local dealer even recommends an Initial oil change at 2,500km / 1,500 mi for the Duramax. At that time, you can switch to synthetic like Delvac 1.

About the only motors where you can't do this to are the medium-duty Cummins used in Dodge Ram trucks. Unless you work the truck HARD for 5,000 miles, the motor could take +20,000 miles to break-in: using a synthetic before then the rings won't seat.

The Heavy Duty Detroit Diesel, Cat's, and Cummins recommend a "break-in" at maximum rated tractor load for the first 5,000 miles before switching to Delvac 1. Those motors broken in on a dyno can be factory filled with Delvac 1. The local Cummins rebuild shop now has an engine dyno just to avoid those break-in problems.

inscom · January 30, 2004

...any advantage -OR- disatwantage to change over to syntetic motor oil in my 1997 Chev Silverado K2500 4X4?

She has 87000 miles on the clock!!!

Thanks in advance.

JayMan · January 31, 2004

Well, you run the risk of oil leaks with that many miles on the motor. Especially the rear main, and the valve cover gaskets.

On the other hand, you will dramatically lower wear rates and keep the engine cleaner.

I'd say change them to synthetic from new.

If the motor appears tight with minimal oil consumption, maybe give it a try?

JimWilson · January 31, 2004

...any advantage -OR- disatwantage to change over to syntetic motor oil in my 1997 Chev Silverado K2500 4X4? She has 87000 miles on the clock!!!

You may have some possibility of seal leak, but a 97 isn't all that old so I don't think the risk is too high. But with that many miles on the clock you might want to consider doing an engine flush BEFORE you switch to synthetic. That way, some of the crud and sludge will get removed before you put in the synthetic (which has a tendency to have more detergents additives then dino oil does).