Mobil 5W-30??

Isn't it nice we now continually debate the relative merits of engine oils? :deadhorse:

I miss those exciting days of unintended acceleration and the brake recall!

 

I agree, I have had two done using 0W20 with this Prius at 28K and 50K miles. No problems have shown up yet. I suppose the discussion is mostly academic to me and I wanted some difinitive answers because the question comes up fairly often. If some distinct advantage in engine wear could be gained by using 0W30 or 5W30 I would switch. So far it looks like 0W20 Mobil 1 is doing OK.

There are a lot of automotive experts and professional engineers on this forum and I try to use them to good advantage.

 

Yes there is something wrong with using 5W-30. It's not recommended by the manufacturer.

I live in the Dallas metro. We had a very hot summer this year with about 60 days above 100 and a week above 110. My Prius runs fine on the required Mobil 1 ... 64,000 miles in less than 2 1/2 years and 4 big interstate trips so far. Much 80 mph cruising through a dozen western and central states with no problems. Doesn't use a drop between the 10,000 mile oil changes.

40 years ago 5W-30 would have destroyed most engines because it would have been too light. The difference in bearing clearances and metal technology today REQUIRE the lighter oil because heavier weight oils can actually cause damage.

You need to trust Toyota on this one. They know what they are doing.

 

The 30 is the SAE J300 viscosity rating of the oil at operating temperatures, 50 to 60 years ago most cars ran 30 or 20 weight oil.

 

Thinking of switching to either 0W-30 or 5W-30 oil as I have begun to notice some oil burn at 132K miles. My commute is 160 miles per day which is the reason for the high mileage on my 2010 Prius. Is there a big difference between the two? Is one preferred over the other? I have also heard that substituting one quart of Lucas Oil for full synthetic may help in severely reducing the oil consumption. What would be recommended for this situation? I seem to be burning 1 qt per 1500 to 2000 miles with the 0W-20.....Thanks!

Oh! Thought I would add, I'm in the Gulf South so not much need for the zero oils down here......never gets that cold!