[jayman]

With used oil analysis provided by Caterpillar SOS, I also found some surprises at least with the motor in my 2007 FJ

First of all, my motor has an issue with nitration. I'm wondering if this is why Amsoil released that TSB warning not to exceed the regular oil change interval with their filters, due to sludging and the filters plugging

Running a conventional oil, such as Valvoline 5W-30, the oil was clearly done before 4,000 miles: nitration and oxidation spikes

Running Mobil 1 0W-20 as a "winter" oil - our winters can drop to -40 - the nitration actually caused the oil to thicken to a solid xW-30 range. Around 11 cSt. Oil only had around 3,000 miles

Running Mobil 1 European Car Formula 0W-40, the oil sheared a bit from a virgin 14 cSt to 12.4 cSt. However, all wear metals were VERY good after 7,700 miles running the dealership oil filter. No problem with fuel dilution, condensation, oxidation, or nitration

Running the made in Germany Castrol Syntec 0W-30, had the same good results as the M1 ECF 0W-40, but it did NOT shear.

Tried Mobil 1 Turbo Diesel Truck 5W-40. Ditto

It's easiest for me to get the Castrol Syntec 0W-30 so that is what I run now. I suppose if my FJ had to sit outside in our winters, and not in a heated garage, i'd run a 0W-20 but probably have to change it very often

No personal experience with Royal Purple or Amsoil, but I do have a lot of respect for Amsoil. What I have read about RP, it may be fine in cool climates, but not appropriate for cold climates like min

 

[Zeke]

I totally stand by my statement but maybe should have went into more detail since some people understand oil better then others. By saying the oil is dirty I was meaning contaminated as well, dirt, fuel, and engine particles included. I've done more testing and researching oil than most people. I build race engine and have been competitively drag racing for 15 years. I have records on more then 60 oil samples sent to Blackstone labs for testing of 4 different synthetic oils, Redline, Royal Purple, Mobile 1, and Amsoil. The results are very surprising to see the differences in these 4 supposed high end oils. The most surprising factor being the shear factor of these. The shear factor is the oil's ability to hold it's viscosity rating. You are 100% correct in oil breaking down as a reason to change, but a normal automotive oil filter cannot filter all of the dirt and contamination from the oil. Even synthetic oil is too cheap not to change often. Better safe then sorry in my book.

Most of us are using Mobile 1 synthetic...I'm going with 0w-30 (live in Florida). How does Mobile one stack up in your eyes vs. the other brands you mention above? Thanks for you input.

 

[bartt]

I have been running 10k intervals on M1 extended service (15k 5-30) for some time now. But I am always open to new info on this important topic.
So it would appear that a few guys here are sitting on some important data regarding their favorite ("best") oil.
Cummon guys cough it up. Lets here what you think is the best and why..

 

[PowTron]

This is what I have been doing, and I am at 55K on the truck at the moment.

My Oil, Filters, etc have been fine each time I have changed them. In fact, I bet I could go farther with no issues on my "over the winter" changes when not wheeling hard all summer.

I have been running 10k intervals on M1 extended service (15k 5-30) for some time now. But I am always open to new info on this important topic.
So it would appear that a few guys here are sitting on some important data regarding their favorite ("best") oil.
Cummon guys cough it up. Lets here what you think is the best and why..

 

[FJeep]

I'm blown away and impressed at the level of "oil expertise" on this thread.

I just rolled into my Toyota dealership with 5k on the odometer of my 2011 for an oil change and yep, they said come back at 10k.

My first impression was that this has more to do with the "FREE" 24 months of basic maintenance on all new Toyotas, but according to the information above, my cynicism may not be so well founded.

Still, I will say this: I did manage to get a free oil change at that same dealership at 2k, and now at 5k I checked my oil dipstick and the color is considerably darker than when it was first changed/darker than the "fresh" synthetic oil.

Just my layman's observation. Not sure if that means it has broken down or is dirty or what, but I do spend most of my miles offroad in relatively harsh conditions and I can't help but be skeptical on the 10k interval recommended by Toyota.

 

[FJ&TJ_Dude]

The BMW service is 15,000 miles. I change my jeep oil every winter and put about 5000 miles a year on it the FJ I drive on longer trips and about 10,000 a year so it gets done twice a year. My lawn mower is nine years old and the oil has never been changed and it starts one pull every time. Honda motor.

 

[Moonbuggy]

My lawn mower is nine years old and the oil has never been changed and it starts one pull every time. Honda motor.

Holy Crap! I'd hate to be the guy that buys that lawnmower down the road!:lol:

 

[football751]

Most of us are using Mobile 1 synthetic...I'm going with 0w-30 (live in Florida). How does Mobile one stack up in your eyes vs. the other brands you mention above? Thanks for you input.

Not exactly what you're looking for, but from what I've read on M1 0W-30 isn't the best M1 to use. It tends to shear down to a very light/very heavy 0W-20. The Castrol 0W-30 is a heavy 30 and holds it's weight, and the M1 0W-40 shears down to a light 40/heavy 30, and both are European car formulas, so you get the same performance out of both.

IMO I wouldn't run the M1 0W-30 because of this, especially since it's so hot in FL you're not concerned about having too heavy of an oil. But just my opinion :cheers:

 

[jayman]

I'm going with 0w-30 (live in Florida). How does Mobile one stack up in your eyes vs. the other brands you mention above? Thanks for you input.

Living in Florida, you have absolutely no need whatsoever for the cold pumping capabilities of that oil. With my -40 winters, that is a different story

Comparing the made in Germany Castrol Syntec 0W-30 to the M1 0W-30, the Castrol oil will offer much better protection in hot climates. It's a "true" 30 oil at operating temp, hence it doesn't carry that worthless "energy efficient" label from the API

So it would appear that a few guys here are sitting on some important data regarding their favorite ("best") oil.
Cummon guys cough it up. Lets here what you think is the best and why..

I agree. It's one thing to offer an opinion, another to publish data such as used oil analysis.

Speaking of which, it would be nice to have a sticky under either Engine or Maintenance for oil analysis reports. Folks shouldn't have to trust the Search feature to dig it up

 

[nickfromny]

2011 OM says 5000 miles if on dirt and heavy conditions.
Great info on the oil.

 

[uberschall]

I use full synthetic and change every 10k. I am over 100k with no issues.

Just make damn sure you don't use Toyota of Lewisville.

 

[Datajockeys]

I have been using Amsoil 25K oil change intervals since 1980. No issues whatsoever. A word of caution... There is a lot of talk about extended drain intervals. Please be aware that there is a time limitation of 1yr as well.

 

[ppark]

Definitely an interesting topic. Amsoil has an oil filter they state is good for 15k miles. Is this a reliable claim? I've been a believer but not sure if anyone has info to prove otherwise. I know driving habits and conditions probably play into this but lets assume normal driving conditions, fwy/local mix. Would anyone advise against using their 25k oil and 15k filter, changing around 15k?

 

[football751]

Definitely an interesting topic. Amsoil has an oil filter they state is good for 15k miles. Is this a reliable claim? I've been a believer but not sure if anyone has info to prove otherwise. I know driving habits and conditions probably play into this but lets assume normal driving conditions, fwy/local mix. Would anyone advise against using their 25k oil and 15k filter, changing around 15k?

I started using Amsoil recently and I wouldn't have any reservations about doing that. They actually make a 25k mile filter that fits the FJ, it's just a bit bigger than the stock filter. I believe it's their version of the M1-209.

Just remember that the oil AND filters have a 1 year maximum use as well. For me that'll be the limiting factor, as I don't put anywhere near 25k miles, or even 15k miles, per year on my FJ.

 

[Old Sarge]

Definitely an interesting topic. Amsoil has an oil filter they state is good for 15k miles. Is this a reliable claim? I've been a believer but not sure if anyone has info to prove otherwise. I know driving habits and conditions probably play into this but lets assume normal driving conditions, fwy/local mix. Would anyone advise against using their 25k oil and 15k filter, changing around 15k?

I have been using AMSOIL for many years off and on, when I started using it in my FJ, I also started having the oil analized at different mileages. This is the only way to find out for sure what condition the oil is in. By testing I have found out that even with their 25K oil I need to change mine at about 7500 miles. I always change the filter at the same time. I have a couple of my reports posted on the forum here, so you can check them out.

 

[football751]

I have been using AMSOIL for many years off and on, when I started using it in my FJ, I also started having the oil analized at different mileages. This is the only way to find out for sure what condition the oil is in. By testing I have found out that even with their 25K oil I need to change mine at about 7500 miles. I always change the filter at the same time. I have a couple of my reports posted on the forum here, so you can check them out.

Interesting that it only lasts 7500 miles. Are you using the 5W-30? I just changed mine a couple of months ago with the 0W-30. I plan to have mine analyzed when I change it next, probably after 1 year as that'll be about 7500 miles for me.

 

[RomaBoy]

Most of us are using Mobile 1 synthetic...I'm going with 0w-30 (live in Florida). How does Mobile one stack up in your eyes vs. the other brands you mention above? Thanks for you input.

X2, I guess Bayou_FJ isn't around anymore but would have liked to hear what he had to say about it. Anyway, I know this is an old thread but one I'm very interested in. Back to the main topic from what I've read going with 10k oil change intervals using a full synthetic oil might work for some but not all. It all depends on how the vehicle is driven. A lot of short trips where the oil never heats up is going to require more oil changes due to contamination. All oils get contaminated. I've read (i read a lot...lol) it takes a 35 mile trip to heat the oil up to a point where it will burn off any condensation in the oil. Bayou_FJ hit on this with his contamination comment. I'm using Valvoline SynPower 5w30 with the factory filter and change it every 6 months no matter what the mileage is.

 

[Old Sarge]

Interesting that it only lasts 7500 miles. Are you using the 5W-30? I just changed mine a couple of months ago with the 0W-30. I plan to have mine analyzed when I change it next, probably after 1 year as that'll be about 7500 miles for me.

I've used different formulas, the European blend, 0W30, 5W30 pretty much all the same results. I did my first test at 22,500 miles on the oil, 15,000 and 10,600 miles. I drive a lot 30,00+ a year. I'm changing the oil every 2-3 months. Whatever brand you like, redline, mobil, AMSOIL, all should be submitted for testing to see the condition of the oil and to see if there are indicators of engine problems as well. AMSOIL states that if you go off-road even one time that changes it to the severe rating and the oil and filter change is at 15K, so if your off roading you probably need to change it more often.

 

[Vegas_Nick]

Here is a new study just released from AMSOIL. This may help in your decision process somewhat:

http://www.amsoil.com/lit/g3115.pdf

 

[cmaj7]

These days, I only drive 5k a year, so Amsoil Signature makes sense for me...I change it every July good stuff!!