So. Let's talk oil...

[Jcp385]

I have a 2000 Toyota Echo. I recently changed oil and started using 5w30 Valvoline MaxLife. Today, I picked up some Mobil1 0w30 Advanced Fuel Economy oil today on a killer deal, $10 for a 5qt jug.

My question is twofold:

1. I hear all sorts of rumors about whether you can/should start using synthetic on a high mileage motor (I'll probably turn over 249k miles in a week or two). Some even say once you start using synthetic, you "can't" stop. Who has some good data to back up any of these claims?

2. I have a consistent oil leak. It drops about 1/2qt every 2-3 weeks. Will synthetic make this any worse?

[trollbait]

Decades ago, #1 might have been true.

For #2, a synthetic might clean out any gunk acting as a plug to the leak. So it could get worse. With that many miles, you might want to use a seal condition or just a quart high mileage oil.

[Jay2TheRescue]

My 98 GMC K1500 had just over 100,000 miles on it when I switched it to synthetic. I have nearly 200,000 miles on it now. Truck still runs great, and only uses 1 Qt of oil every 5,000 miles. Pretty much when it hits a quart low I'm due to have it changed anyway, so I don't generally add anything to it. When I first switched it to synthetic I was using Mobil1 5W30, I'm currently using Mobil1 0W30, and changing the oil every 5,000 miles.

I agree that #1 is old school thinking. Now, almost all oil is at least semi-synthetic. I would not be surprised if there are oils that are technically synthetics being marketed as conventional.

[Draigflag]

5000? I thought synthetics can do way more than that, at least 20,000 between changes?

[Jay2TheRescue]

5,000 is easy to keep track of... If my odometer reading is divisible by 5,000 I know its due. I probably could do a longer interval, but as it is right now, its a 17 year old vehicle with nearly 200,000 miles on it. Every 5,000 has worked well for me so far, so I'm hesitant to change it.

[itripper]

My personal experience with using synthetic and especially the 0 vs 5 wt cold is your leak will get worse, and synthetic oil costs a lot more. That is a crazy low price for that oil you got!

[RunningOnFumes]

Originally Posted by Jcp385

I hear all sorts of rumors...

On the internet and forums, right?

Best contact Mobil or whoever you choose to use.

[RunningOnFumes]

Originally Posted by Draigflag

5000? I thought synthetics can do way more than that, at least 20,000 between changes?

At least 20,000 kilometers.

And this in a country where the cars are actually run hard as in 120+ MPH on their highways.

[Jcp385]

Originally Posted by RunningOnFumes

On the internet and forums, right?

Best contact Mobil or whoever you choose to use.

Among other places.

One of the guys I work with is a mechanic for his day job. He advised against it. Most of my gearhead-y buddies I hang out with just dump heavier oil in when they are in doubt. I'm not overly worried - it's a throwaway car, I got offered $300 for it at the local Toyota dealer's "Tuesday Buyback Event"

[Draigflag]

Originally Posted by RunningOnFumes

At least 20,000 kilometers.

And this in a country where the cars are actually run hard as in 120+ MPH on their highways.

Exactly, even in Germany where you can legally drive at 200 MPH if you want, the German cars have 20,000/30,000 mile oil changes. I made a topic about it a while ago.

http://www.fuelly.com/forums/showthr...ight=excessive