Short commutes + dino oil = corrosion vs 1yr changes on M1 = spotless

Not open for further replies.
Aug 12, 2003
I'm not out trying to prove some point about synthetics, but I have a side-by-side comparison that you guys might find interesting. I maintain my female friends 4cyl turbo Audi now and found the valvecover and dipstick to be clean, in a like-new condition. I asked her what she has done over the last 5 years/60k for oil. "Mobil 1 every year" she said proudly. He ex is a BMW guy, I guess he suggested it. I thought, "all that will change".
Oddly her brother-in-law lives across the street and bought a similar *used* car, very low miles -in the teens. He knew the owner took only a 1 mile daily commute in it, her office was in-sight of her home. Dealer inclusive-service dictated 5000 mile (V6 had 7500 mile intervals, maybe this car had the longer interval, essentially once-a-year also) changed with Castrol GTX 15w-40 it's the dealer pick. I said, "how about seeing a snapshot of what dealer oil and short commutes does"... I pulled the dipstick, it had the most thick varnish I have ever seen in a modern car and was totally pitted, deeply. He was shocked, only a 20k mile car at this point. So, Mobil 1 did the job. Dealer Dino did not. Just a thought. I have changed out completely to synthetic on all 6 cars I maintain. Rotella Synth is my poison.

[ October 06, 2003, 11:14 PM: Message edited by: TSoA ]
...Too bad Rotella-T "synthetic" is not actually a synthetic

Originally posted by Intelman34:


Originally posted by Jelly:
...Too bad Rotella-T "synthetic" is not actually a synthetic

It it still a VERY good oil though.

I would pick Delvac 1 though.

Yes it is, especially for the $12.88/gallon price at Wally-World!
Yes, Rotella is good for $3q. I maintain quite a few cars, I purchase almost 70q of oil a year, so price is an issue. Rotella has a consistant formula, HT/HS of 4.0 and is a Long-Life oil. "Synthetic"? Shh, my cars can't tell.
I have noticed the same thing between my miata with mobil-1 and my sons Mazda Millinia on Dino. Dip sticks are identical and mine is spotless his has a very heavy varnish on it. We have auto-rx in his now so we will see if it will clean out this heavy varnish.
I think you are condemning the oil and not the 1 mile commute on the brother in laws car. What was the change interval for the dealer changed oil? Would any oil have done any better?

On the other side would not most good oil work for 1 year and reasonable mileage intervals and good conditions?

I think a better side by side test is in order.

But I still think M1 is a superior oil and I am thinking of changing one of my cars over to it so I am not bashing it yet.
My family has used dino esclusively in short trip vehicles with 3,000 mile changes and there is no sludge or varnish to speak of what so ever, especially on the dipstick. I persoanlly think that with short trip/cold weather driving using dino, you have to stick with shorter intervals to get all the moisture and fuel out of there. Or just go on a nice long Sunday drive on the highway.
The car with dino oil was probally changed yearly at inspecton. Of course the short commute had a lot to do with the deposits and pitting, only the change interval was the same. I am putting this forward as an example of what not to do,(dino oil on short commutes) verses doing what my friend did - bare minimum service with Mobil 1 worked. You can't extrapolate too far except what not to do and what is ok to do provided the oil is M1 or better and the commute is sufficient for normal oil temps.
Short commutes equals need for high TBN.

Group IV and V PCEO synthetics have higher TBN's than comparable passenger-car mineral oils.

I'll use a "dino" oil for short trips, but it has to have a high TBN, such as a 5w-40 or 15w-40 mixed-fleet oil.

[ October 08, 2003, 12:13 AM: Message edited by: Jelly ]
I'm not bashing anyone's choice of oil here either. But this is in no way an analysis that one should draw any conclusions from; reason being: not for certain what the exact oil and changes and how the used car was handled.
I believe Mobil 1 is a very good oil, but I also believe that the SL rated regular oils are also very good oils now, and would keep an engine clean and protect very well if used appropriately.
BY the way, I know this from personal experience (synthetics and regular oils).

Good Day,
Not open for further replies.