15,000 mile mobile 1

[allenmehrer]

Two weeks ago I ordered new rims/tires. So for a week I roasted my old tires whenever I had the chance. Of course for that tank of gas my mpg was loow since I had many 4,000-5,000 rpm revs.

 

After my new tires were on my mpg never improved. So I questioned my oil.

 

After changing it only 2,500 miles into the oil life, it came out black as night!

 

A short drive after reminded me of how my truck USE to drive. NO more high shifts looking for power. Hopefully my mpg numbers will improve again.

 

By the way I went back to mobile 1, the regular stuff!!

 

I'm going to get the oil checked to see if it lost its viscosity.

 

I personally don't think this oil was designed for our hard working engines!

[eshoremd]

Two weeks ago I ordered new rims/tires. So for a week I roasted my old tires whenever I had the chance. Of course for that tank of gas my mpg was loow since I had many 4,000-5,000 rpm revs.

 

After my new tires were on my mpg never improved. So I questioned my oil.

 

After changing it only 2,500 miles into the oil life, it came out black as night!

 

A short drive after reminded me of how my truck USE to drive. NO more high shifts looking for power. Hopefully my mpg numbers will improve again.

 

By the way I went back to mobile 1, the regular stuff!!

 

I'm going to get the oil checked to see if it lost its viscosity.

 

I personally don't think this oil was designed for our hard working engines!

 

<{POST_SNAPBACK}>

 

 

 

you have no evidence to make that claim. what makes your motor so "hard working"? you have a 2wd 1500. any oil will be black after a thousand miles of hard driving.

[Mighty HD]

It's spelled MOBIL one

 

 

I think the 15k Mobil 1 is dark to begin with due to the additive package.

 

Your best source of info is www.bobistheoilguy.com

[mcreyaufmiller]

When the oil comes out black, that is a good thing. That means it is doing it's job. Maybe you should look in another direction for your loss of MPG?

[Jansen]

Not looking to start an oil war here but Yes if the oil was black it is doing a great job of cleaning your engine. Secondly, the Mobil Extended performance is designed for our trucks (5.3L V8 in mine). Personally, I run 15w50 mobil 1 in mine. I know, you think I'm nuts, however it worked fantastic in my Comanche with the 4.0L I6. Of course, I talked to GM and Chevy dealers and all we debated on was who was better, Shell Rotella 15w-40 or Mobil 1 15w-50. If you are going to have the engine running that high of an RPM (4000 to 5000) on a regular basis make sure you run a synthetic as it will not break down so easy.

[az'03Silverado]

I don't care what anybody says, 15,000 miles is too many on an oil change (unless you're operating a leased fleet of vehicles that you don't care how long the engine lasts). Even if the oil can take it, I don't think a filter can. It's kind of like Prestone's Extended Life coolant (like dex-cool) that states a 150,000/5 year life. Yeah, maybe. But the hoses and thermostat won't last that long so their claim is useless.

[allenmehrer]

Sorry for the oil war.

 

I'm just saying that I ran my "little" truck d**n hard for one fuel run and i feel like the oil broke down.

 

A few of you are right though, I have no evidance. Just black oil.

 

By the way I'm not putting down mobil 1. I love their oil and I'm still running it now. I just feel like the 15,000 mile blend wasn't designed to be run in an engine thats hitting high rpms. Even bob the oil guy said that additives cause oil to foam at high rpms.

 

Then again thats just my 0.02$

[Jansen]

Hey hey let me clarify! I would never take my oil to 15000 miles. I know one guy who did the 10,000 miles but changed the filter at 5000 and added a fresh quart. For me, all city miles now, I won't let it go past 4,000 before i change it. I'm partial to mobil 1 though.

 

Jansen

[Frozen001]

Have you ever thought the the drop in MPG was because the camputer "adjusted" when you beat on the truck for that one tank of gas. I am sure it would have "adjusted" back to normal after anouther tank of normal driving. People forget that the most engine computers will make adjustments to the driving style od the driver.... so you beating on the truck cause it to adjust it programming enough to effect your mpg. Also you changed tire sizes right after this so that could have also affected your mpg...

[allenmehrer]

Good call on that computer reprograming idea. I'm kind of foot in mouth about that since I'm sure that had something to do with it.

 

I changed too many variable at once to know which one was the problem; driving style, tires, and oil. It could really have been any of them.

 

I'll admit that I'm a rook when it comes to oil. Though I can tell you that I KNOW my truck and I know when something is a miss. Also I'm not basing everything off of mpg. Peddle pressure, downshifts up hills, and high shifts points just cruzin around town are all factors.

 

The only way to solve this is to get the oil tested.

 

Until then, theres only going to be "regular" mobil 1 synthetic in my engine.

[Black02Silverado]

 

 

I'm going to get the oil checked to see if it lost its viscosity.

 

 

 

 

 

 

 

Keep us posted on what the oil analysis turns out to be. With only 2500 miles on the oil I would think it was well within specifications. I would bet the TBN was still high. Would be interesting to know.

[JBZ71]

Mobil 1 EP,15,000 mile oil, has alot more detergents and supersyn in it than regular M1,so alot more cleaning was going on with the EP oil..

 

Running a 15w40 or 15w50 oil in a 4.8,5.3 is probably not a good idea and I am suprised a chevy,gmc dealer would actually debate which is better..Unless your engine is well on it's way to worn out that weight oil is not giving any real benefit,maybe doing more harm than good..Low number on the oil weight is the weight at start up,you want the oil circulating and hitting all parts as quick as possible,the 15w isn't getting it done as efficently as a 5w...I suggest you read articles written by Dr A E Haas over at www.bobistheoilguy.com,he has a Ferrari that specs a 10w60 oil or some such ridiculous thing and he runs 0w20 M1 with remarkable results...Something to explore and find out more,cause thicker is almost always not better..

[neoh77]

Mobil 1 EP,15,000 mile oil, has alot more detergents and supersyn in it than regular M1,so alot more cleaning was going on with the EP oil..

 

 

<{POST_SNAPBACK}>

 

 

 

I was thinking the same thing....with more detergents in the oil it probably turned black due to increased cleaning. Maybe after 3 changes that would clear it up?

 

That bob is the oil guy site is interesting particularly with air filters. I'm sticking with my HD ac delco filter. Bob claims it makes a noticeable difference what sort of air filter you use and the more restrictive paper elements filters with lots of surface area just do a better job.

 

Anyone mess with Diesel oils over here? talk about lots of detergents! Never tried them in a gas engine personally.

-Matt

[MS3DALE]

I agree,I think a 15W-40 or 15W-50 is waaaay to heavy for our trucks (Gas that is,diesels are another story),especially in cold climates in the winter.

[Frozen001]

Though I can tell you that I KNOW my truck and I know when something is a miss. Also I'm not basing everything off of mpg. Peddle pressure, downshifts up hills, and high shifts points just cruzin around town are all factors.

 

 

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When you changed your wheels and tires was there a change in overall tire diameter???

 

Changing shift pints to me means that the wheel speed has changed, which makes me think it might be more of a tire/wheel combination problem that you are feeling.

 

The automatic transmission are programmed to have the factory tire sizes on the truck you change the wheel diameter and you should expect different shift points.

 

The problems you say you have do not seem like oil related problems.