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Multi-weight advice

Driving a 2001 Toyota Corolla, 1.8l auto. Vehicle has 225,000 miles and is driven in Southern California. Mostly freeway, but definitely some city driving.

Would there be any benefit to moving away from Toyota’s recommended oil weight? I have browsed the discussions and it seems there are a number of posters who insist on never varying from the Owner’s Manual. Okay. I appreciate that thought.

BUT. I’m still curious about how thick I should go given that it’s getting warmer in an already warm area, the car IS burning a bit of oil. (about a quart every three months) and I’d like to use knowledge and experience to make a decision since circumstances alter cases. 5W-30 seems fine for a catch all soultion. But it assumes ALL weather on a new vehicle, so… wouldn’t those in warmer climes benefit from moving to 10-30 in most every case? Wouldn’t higher vicosity be preferrable considering the mileage on the engine? BUT, would moving to 10-40 cause sludge or fail to flow as desired in a high-tolerance engine such as this (or as it was when it was new.) How about 20-50 even? Straight 30 or 40 weight?

If you aren’t burning oil at a rate of more than one quart every thousand miles, I would continue to follow the recommendations in the owner’s manual. Much of the wear on an engine is at start up and even if it is 90 degrees outside, an engine that is at ambient temperature is still cold.

Good advice by Tridaq. However, if you only driving in Southern California, you could use a 5W30, or a synthetic 0W40 all year round. I agree that cold starts cause a lot of engine wear, so I would stay away from a 20W50, although that oil is used extensively in that model Toyota in tropical countries.

If you get a bullletin from Toyota that 5W20 is OK, ignore it. That oil is now used in the new Toyotas, and would probably cause excessive oil consumption in your 2001 model.

As I got older, I have swung toward the side of “If it ain’t broke, don’t fix it”. As long as 5w30 is working for you, I’d say stay with it. When it no longer works for you, 10w30 would be a good choice. I would not recommend 10w40 or 20w50, but if 10w30 doesn’t work for you, then consider 15w40 for diesel engines.

Given your location and the high mileage, switching to 10/30 or even 10-40 is not going to change the course of history…It’s simply not THAT big a change…

The only difference in the way 5w30 vs.10w30 would perform would be on cold start ups. Both oils have the properties of a 30 weight after the engine gets up to temperature. One has the properties of 5 weight on cold starts and the other the properties of 10 weight. If you were using a significant amount of oil a 10w40 or even 20w50 might have some advantages. I’m still old school and run 10w40 in all my cars and have never had any problems other than the fact my '88 Escort is starting to have some sludge problems, but with over 1/2 million miles and having been driven on dusty construction sites for the first 12 years of it’s life I’m not surprised.

I have good luck using 15-40 in high mile vehicles. It seems to help with slowing oil burning. My Chevy called for 5-30 when new. I now run 15-40 in it. I have over 330,000 on it. Its never been a oil user as it only uses a QT if I go over 6000 miles between oil changes. The oil presser is down a bit now about 32psi at idle and 55psi at 60 mph. That with a real gauge.

Well? You’ve made it to 225,000 miles with minimal oil burning using the recommended oil. Why change now?


11 years, 225,000 miles. That’s 20,000 miles per year. 1600 miles/month. Approximately one quart of oil used every 5000 miles?

Don’t change a single thing you’re doing.

I would stick with 5W-30, like others have said. I certainly wouldn’t go above 10W-30 without a good reason, and I don’t see that you have any reason to go above that. Age/mileage alone isn’t a good reason. If your engine was burning or leaking oil, that would be a good reason.

Avoid 15W40. It shouldn’t be used with catalytic converters due to zinc that is in the oil. If you do your own oil changes, use one quart of straight 30 weight. It will thicken the oil a little and may stop some of the oil loss. At this point in the life of the engine, you can feel free to try almost anything. If you are inland and not coastal, try two quarts. It’s hot inland, for those who don’t know California weather. It’s cold nearer to the shore.

pleasedodgevan2 Prove this. I have been using 15-40 for years with no problems. I just checked the label on a bottle of 15-40 Wolf Head oil. There is no mention of Zinc or it not to be used with catalytic converters.

Zinc is a catalytic poison, but it takes a lot to cause problems. The real problem used to be zinc was accompanied with phosphorus which significantly worse for cats. The only 15-W40 Wolf Head oil I’m aware of is for diesel. Diesel cats work very differently then gasoline ones, and it’s possible that the zinc doesn’t even affect them. If you dig up the MSDS for the 15-W40 oil it probably lists zinc or a zinc compound as one of the components

The MSDS I was able to find, but can’t guarantee its the exact stuff you’re using:

You can also look at the wikipedia page for catalytic converters which discusses zinc and phosphorus poisoning a little:

As you can see the zinc used in 15-40 is deferent Than what was damaging cat’s. Also note there is less than 1% of it in the oil.
From wikpedia:
Phosphorus is another catalyst contaminant. Although phosphorus is no longer used in gasoline, it (and zinc, another low-level catalyst contaminant) was until recently widely used in engine oil antiwear additives such as zinc dithiophosphate (ZDDP). Beginning in 2006, a rapid phaseout of ZDDP in engine oils began.[citation needed]

So you all were using it up till 2006.

Also I checked Wolf Heads web site It states it can be used in gasoline engines.

@pleasedodgevan2, you must be speaking about oil made for diesel engines.

15w-40 “Universal Fleet Oil” is rated for both Diesel and gasoline engines. Since it still has the zinc extreme pressure additive, it’s usable in older flat-tappet engines which need this anti-scuff protection.

Today, to keep the EPA happy, its marketing is aimed at Diesel engines and it’s suitability for gasoline engines is not promoted but if usually carries the API gasoline certification…

Approvals and Recommendations:
Shell Rotella® T SAE 15W-40 10W-30
• API CI-4 PLUS, CI-4, CH-4, CG-4, CF-4, CF X X (not CI-4 PLUS)

The API SL,SJ and SH are gasoline ratings…

In your current 5W-30 oil, the 5W applies only to cold start up, and the 30W is what the oil is supposed to be when the engine is at normal operating temp. So, no need to change the 5W part. If you wish you could change to 5W-40 or 5W-50 if there are such oils available. In S. California I’d see no real issues going to a 10W-40 since the motor is likely at 50-70 degrees at cold start up.

At this point in the car’s life you can experiment with oils and use whatever you like. Some brands of motor oil burn off faster than others, so you could try using the same weight oils in different brands too. At 225K miles you’ve gotten your money’s worth out of this car so whatever you do it has already given you more than good service.

Happy to see all the posts, some with research. Also happy to see that 2006 has become the old days. Now I don’t feel so bad about the age thing. It was actually 2006 when I bought the 05 Ford E-150 which had a sticker that said the oil change was done with 15W40. I wondered if the dealer used that stuff in everything with complete disregard for specifications and stuff. It only had 17,000 miles on it. The old days. Wish I could still fill the tank with $88.

“Wish I could still fill the tank with $88”.

In the old days I remember, you could have filled the tank for well under $10… As a child we would guess how much it was going to cost to fill dad’s car up and the guesses were always under $5. I remember gas being $0.289 a gallon regular price and one time when a new station opened up in town a gas war started and prices dropped to $0.119 per gallon and the new station was giving away a free candy bar with each gallon or each dollars worth of gas I can’t remember which on top of the low prices. Now instead of having gas wars they have wars for gas. Those were the GOOD old days. When I started driving gas was around $0.45 cents a gallon and we thought that was high. Oh how things have changed in 36 years. I think my first job out of high school I was only making about $2.65 an hour too.