Best Oil for Short Trips?

[ARH_0700]

I know that it's different for every engine, but I want to know everyone's opinion on what's the best thing to do in general for short trip situations. I drive my car (G35 coupe with the VQ35DE) to school and back every day which is about 6 miles one way. The drive takes about 15-20 minutes. I don't have an oil temp gauge but my coolant takes about 5 minutes of slow driving and idling at traffic lights to reach operating temp (during the winter). The car usually sees a few 30 minute trips on the weekends but not much longer than that. My question is when I switch to synthetic at 10k should I go with a thicker oil like Mobil 1 0w40 / Rotella T syn 5w40 or stick with Mobil 1 5w30? I'm leaning on using the 40wts because this engine seems to like thicker oils and there would be more room for fuel dilution? What is the general opinion, thicker or thinner for short trips? Thanks to anyone that read this long thread and can offer their opinion

 

[jthorner]

It doesn't sound like you put a lot of miles on your car. Personally I would use a good non-synthetic and change it twice per year to flush the accumulated contamination out of there.

John

 

[Drew99GT]

From what I've seen, these engines do indeed show dramatically lower wear numbers with 40 weight over 30 weight. So.........., I'd go with Mobil 1 0w-40. The HDEO 5w-40s are pretty freakin thick, even at 40C compared to 0w-40 Mobil 1 or even some other Passenger car only 5w-40s (like Chevron 5w-40). For that reason, I'd stay away from Rotella or Mobil 1 Truck and SUV for short trips. Yes, they are 5w, but look at the 40 C viscosity. GC 0w30 would be an even better bet for these engines, as the Mobil 1 0w-40 will essentially end up at the viscosity that GC starts at.

 

[ARH_0700]

I actually have 5qts of GC and will run that first along with a used oil analysis, but it's just too hard for me to get GC where I'm located. I have to drive 45mins to get to the nearest autozone and to me that's not worth it when I can get Mobil 1 0w40 at my nearby advance auto. I will likely keep the oci short, maybe around 5k, but I want the cold start advantage of syns because this car gets driven mostly in the winter (I am out of the country 2 1/2 months every summer).

 

[ekpolk]

As you know, I had one (so far) great UOA on my 04 G35 with GC. FWIW, I consider the Mobil 1 0w-40 to be the next-in-line after GC for this engine/vehicle combo. If my GC supply dries up (or I get tired of using greenish oil...), this is what I plan to use. You'd need, of course, to experiment some to establish your ideal OCI.

Look harder for GC. . .

 

[ARH_0700]

Yeah there's no doubt that green stuff works wonders in most engines

I would really like to know why only autozone carries this oil. Advance auto has all kinds of weird grades and brands but not GC.

 

[Palut]

quote:

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Originally posted by Twilight_Blue_G35c:
I have to drive 45mins to get to the nearest autozone

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That could be a good opportunity to burn off some contaminants. Just buy 30 or 40 quarts, then you wont have to make the trip again!
After our little study comes back and we know what GC is made of, that may be an even better idea.

 

[Market525]

To add my comments to "short trip" oil - my wife's 2002 Jeep Liberty sees only about 8,000 miles a year. We laugh, as some weeks she only puts 10 miles or so on the car.

Last year I used Amsoil 5w30 full synthetic, with their filter. I changed the filter and topped off at the 6 month mark. I had to "force" myself to make it a year, as the oil did not look or smell good to me.

Sent a sample to OAI, and the oil came back exactly as the oil on my Tundra does - suitable for continued use, but flagged "abnormal" for viscosity (thickened). I changed the oil anyway, because coming into a cold Maine winter I did not want thick oil in the car. TBN was still good.

You'd be pressed to stress an oil harder than this (IMHO) - short trips, below average outside temps for many months of the year, etc. The Amsoil seems to do the job.

I will dig out the analysis report and post it later tonight or tomorrow in the Used OA section.

 

[427Z06]

IMHO, I'd do a used oil analysis or two to see if fuel dilution is an issue with those short trips and all. Then I'd think you would be in a better position to make a decision on what you want to use. For example, if you do see substantial fuel dilution, you may want to go with a less expensive syn-blend and change more often.

 

[ARH_0700]

I guess a used oil analysis will help alot in determining the right oil, and I have a blackstone bottle sitting on my desk, but it will be a while until I reach 10k

It will be interesting to see the difference between GC and Mobil 1 0w40 though.

 

[M3 Mitch]

I think changing your route to "take the long way home" and drive about 10 to 15 miles, preferably daily, would be at least as important as getting the optimum type of oil. I have read in an old SAE paper that synthetics show most of the fuel mileage gain in relatively short trips.

But if you don't get your oil hot enough to burn off whatever contaminants you get into the oil, they will accumulate.

If practical for you, an electric engine block heater would be helpful IMHO. I like the ones that go in the soft-plug holes and put an element directly into the coolant. This would not be to aid cold starting, specifically, but instead to get your engine up to temperature sooner.

 

[Tones]

You need to change the oil a little more often, say every 3-4 k because it takes a long time to accumulate miles and the oil gets diluted. A full synthetic would be a waste of money to change this often.

This is where the Schaeffers Supreme blends shine, IMO. Do a search for used oil analysis of Schaeffers and look for those with fuel dilution. Shaeffers still seems able to protect the engine. Schaeffers seems able to protect even with coolant present in the oil. Even better, this oil is a little cheaper than full sythetic.

Here is one example.
Here is another.

 

[TheTanSedan]

Be sure to use LUBE CONTROL and FUEL POWER.

Change oil annually, or 10,000.

 

[TomJones76]

quote:

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Originally posted by TheTanSedan:
Be sure to use LUBE CONTROL and FUEL POWER.

Change oil annually, or 10,000.

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TanSedan,

I'm going to say that your reccomendation is lacking in wisdom unless he uses used oil analysis to validate the strategy.
He should go 3,000 miles, sample for UOA. Interpret results. Condemn the oil or not based on its state.
Then send another sample in at 6,000 miles and based on the UOA from that, THEN determine if you want to try 10K.
Plus, with my strategy, we get to comment on the used oil analysis he posts.

 

[Bryanccfshr]

[/qb][/QUOTE]TanSedan,

Plus, with my strategy, we get to comment on the used oil analysis he posts. [/QB][/QUOTE]


That is a great strategy. I of course would love to see UOA with Dino and LC worked up to 10k mile OCI's. I just don't drive enough to do it in a reasonable amount of time myself. I would think a commuter vehicle that gets ideal driving conditions with a hearty dino like delo or even MC can do it. But I would love to se an economy oil like Supertech with LC pushed that far. Just to see what it looks like. at 10k(ideal) miles.

 

[LarryL]

This may sound a little of the end but in a fleet of cars there is the owner's car that is driven about 10 miles a week, sometimes less. We have had problems in the past with maintenance so we put a block heater on it that is set with a timer to heat the oil up once a week for about four hours... end of the problem. Not much science, but it works.

 

[Bror Jace]

Actually, I'm in something of the same boat myself, now. One way trip in the morning went from 24 miles down to 7.5 and about 40 minutes down to 13.

Up until my change of jobs, I was using Schaeffer 5w30. But went I changed my oil at the beginning of December, I went with a mix of Scaheffer 5w30 and Mobil 1 0W03 to cope with the -20F we get here during the cold snaps.

I'll be doing a used oil analysis this spring. I'll switch back to 100% Schaeffer then, too.

Even though my annual totals may only be about 8,000 per year or less, I'll be doing 2 oil changes per year.

When the weather warms up, I may pick a different park-n-ride lot and my commute may be only 2.5 miles each way!

--- Bror Jace

 

[yannis]

This is an interesting article about temperature and mineral Vs PAO oils.

http://www.machinerylubrication.com/article_detail.asp?articleid=586&relatedbookgroup=Lubrication

PAG synthetics. Note in particular the performance level comparison for temperatures below 80°C..>>

 

[Mickey_M]

quote:

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Originally posted by yannis:
This is an interesting article about temperature and mineral Vs PAO oils.
http://www.machinerylubrication.com/article_detail.asp?articleid=586&relatedbookgroup=Lubrication

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I am not sure about the applicability of this to engines, where detergency and other issues play an important part in oil performance.

I note two other questions left unanswered:

There is no actual test data supporting the hypothesis that EHL film thickness translates into differences in bearing wear.

There are no comparisons of fully formulated lubricants, since straight PAO is rarely used and the addition of esters provides significant boosts in EHL film thickness.