Not true, under specific conditions 15K can be considered OK for an oil change. Let me elaborate. GM recommends that Corvettes, which use Mobil 1 synthetic 5W30, to change oil and filter every 15K. The reason GM can instruct corvette owners to is because the entire engine is aluminum and has a very efficient cooling system which can dissipate heat much faster. Avoiding deterioration of the oil My Durango has a 5.9 cast iron block. Cast iron is very efficient in heat uniformity but one drawback is its ability for heat retention, even after the engine is not running. The Mobil 1synthetic 10W40 begins to breaks down for me at 5K. Oil life will depend on how long and hot your individual engine runs. Read the Amsol claims and I’m not willing to risk my engine because the performed a study on a stock Honda engine.

 

I think it's a matter of opinion. Do you really trust their advertisement to keep your engine clean,protected, & lubed up to 15,000 miles...if you do go for it, if not then don't! I always changed my oil every 3,000 miles with Mobil 1/Royal purple oil and Mobil 1/K&N oil filter. It's your engine, you can do whatever you want with it.I dont trust any oil to stay clean,keep my engine lubed & protected for 15,000 miles!

 

thats exactly it...all personal opinion. I think spending $40+ on an oil change every 3,000 miles gets a little pricey...personally I'm comfortable with going 8-10k on amsoil no problem which is still better than going 3,000 on conventional. A lot of people are just so stuck on the 3,000 / 3 month interval system that they are inclined to thinkthe same with synthetic. In reality, conventional and synthetic are vastly different oils...

 

husky017

What is the difference betweenFULL synthetic and PURE synthetic? [>:]

I have never seen this before. [sm=feedback.gif]

Souds like a sells line to me.

 

^ Agreed with Hydrashocker!

Amsoil needsseveral independent testto confirmthis.

 

Full synthetics are petroleum based, because they use a petroleum base stock. Pure synthetics are just as described.. PURE SYNTHETIC, as like designed in a lab.

 

That answer clears absolutely nothing up...

 

Well sorry cesspool i'm not a lab technician for amsoil. I do know for a fact that Mobil 1 and other popular synthetics are a FULL synthetic and AMSOIL is a PURE synthetic, and there is a difference between the two. If you really need to know the chemical difference then google it or something.

 

mobil 1 15w50... had 185k on my 2000 5.9 before I sold itand it was running perfect.

 

Amsoil... lost all respect for them back when they suggested using there special filter replacement cartridge that you placed a roll of toilet paper inside of to use as a filter. Crazy to think about that now, but back then it was worth a risk. Unfortunately for those that had tissue clumps through out their motor and Amsoil with egg on their face, the risk turned out to be costly.

Oils... M1 has a real synth and a oil based version. Read the labels. Real synth is real synth BTW. There is no oil syth, LOL. Better yet, read ALL the info on oil you could ever want to know about over at http://www.Bobistheoilguy.com

Filters... while at http://www.Bobistheoilguy.com, look for the filter study. The cut open about 20 different filters, compared the design, flow, materials, etc to determine the best and the worst. Avoid Fram (shocked me too) and Purolator and go with Wix, K&N or Mobil1 for a great filter.

Oil change intervals... NO ONE should EVER guess what the oil interval should be for their oils. Nor should they blindly follow oil manufacturer specs. First, the longer intervals of the specilaty oils are intended to justify their higher costs. Second, each engine and driver drives differently. Everyone should get to know thier motor by the use of an oil analysis. You can predict failures in advance of parts breaking based on trace metals found in YOUR oil as well as develop a baseline with your first oil change that gets the analysis and then compare the results to each analysis thereafter. Only the analysis can tell you if there are friction fighters remaining in your oil after a stated interval. The analysis will tell you to extend your milage between intervals or to shorten them based on the results you get back. These results are from YOUR OIL SPECIFICALLY via analysis and shows how yours stacks up against all others with the same type setup as you have.

IF you listen and choose to use an analysis (do it once and you will always do it. I did the first two back to back and now do it every other oil change) you should use http://www.blackstone-labs.com . They will send you FREE test and collection kits AND send you both paper and electronic versions of your results in a very timely manor. ANYONE who claims to be an auto enthusist or loves their rig NEEDS to be checking the oil via analysis and Blackstone Labs is one of the fastest and best there is to use. There is no reason to guess on the oil change interval regardless of the oil you use.

I run Mobil1 in everything, the engine, the diffs, my lawnmower LOL, etc. Back when I ran Dino oil, it was always Penzoil. With proper oil change intervals (3K on Dino oil and 5-6k on M1 now) I have NEVER had an oil related engine issue. In fact, zero engine issues at all. Every auto exceeded 150,000 miles on the odo, from 4 cylinders to v-6s to my 5.9L now (178,000+ BTW and solid as a rock)

There, the definitive answers. That should close this thread nicely I'd say.

HTH!

IndyDurango