Will this Oil damage my Engine

engines
oil

#1

Recently had my oil changed at the dealership. Customer supplied oil. Mistakenly purchased 5/20 Synth oil. Toyota Sienna manual recommends 5/30. Will this 5/20 damage my engine? Should I change it again back to 5/30 immediately or can I wait for the next oil change? Theoretically the thinner oil might lubricate where the 30 might not go, but my theories might be, as they say, bogus.

Certainly don’t want to cause unnecessary wear to a very expensive engine. The services dept didn’t say a word about it when I picked up the Sienna… any knowledable info would be MOST appreciated.


#2

In all likelihood, no, absolutely no damage will come from this. If you plan to make some trips through mountainous country during hot weather, you might think about changing it just for peace of mind, but really, it’s not that big of a deal.


#3
It might be a big thing if you have a lot of miles on that car and you were planning to drive in somewhere hot.  Since winter is coming and it likely has less than 100,000 miles it should not be a probem.

If the oil light comes on, pay attention, let it cool down before continuing and have it changed then to the specified oil. Frankly I doubt if it will show up as any kind of problem.


#4

No problem . . . if you want to make the oil weight “heavier”, add a can of STP. I wouldn’t even give it a second thought. Rocketman


#5

Someone finally found a useful application for STP oil treatment! Go for it!


#6

The general engineering philosophy on lubrication is to use the lightest oil that will adequately lubricate the moving surfaces. Assuming your engine is relatively low mileage and was properly broken in (you did RTFM on break-in didn’t you?). If you have excessive clearances due to aggressive break-in or high mileage or excessive oil change intervals, then the ligher oil may “burn off” faster forcing you to add oil between changes.

I would replace the oil with the proper weight, but then I’m a bit of a fanatic on longevity and maintenance. I don’t think you’ve caused any damage.


#7

I would replace the oil with the proper weight, but then I’m a bit of a fanatic on longevity and maintenance. I don’t think you’ve caused any damage.

That’s, more or less, what I was thinking.

BTW, how did the dealership manage to put in the incorrect oil without noticing?


#8

Customer supplied oil. Mistakenly purchased 5/20 Synth oil.

The manual might also recommend a 5/20 for varying seasons. the 5/20 should help out a bit in winter temps.


#9

Yup, I read that, but some tech at the dealer actually dumped it in the car. One would hope that he would have asked, “are you sure?” first. It would have saved the OP having to replace his oil.