5-20w vs. 5-30w oil

knitty

I have a 2002 Windstar and I took it to have the oil changed. When I got home, my huband looked at the invoice and noticed that they had put 5-30w oil and he says it was supposed to take 5-20w. Is this a huge problem that needs to be corrected immediately, or can it slide this one time? My husband is all ready to start a big fight with the place and I just want to understand why. Thanks for any help.

blufz1

No need for your H to have a seizure over the oil. Just go back and get it changed to 5-20. They'll probably do it for free or cost. Hope this helps.

52132

I put 10w30 in mine, it provides better engine protection during hot weather [like in Florida]

old89lsc

Around 2000, Ford (and perhaps, Honda) changed the engine oil specification from 5W-30 to 5W-20 for many vehicles. This was done without any actual engine mechanical changes. The reason was to improve fuel economy. The 5W-20 is less viscous (thinner) at operating temperature and, therefore, reduces the internal friction losses. Actually fuel economy gains (<5%) aren't likely to be noticed outside of the controlled environment of a lab. In other words, you and I can't tell the difference.

The downside is that, given the same base stock, a 5W-20 oil will have less viscosity index improver in it, meaning that over time it may degrade to a less suitable oil more quickly than would a 5W-30 oil. The difficulty of the 5W-20 grade can partly be seen in that it is only offered in a synthetic blend formulation, typical base stocks would be dangerous to use in such an application.

In the end, I prefer synthetic 5W-30 over 5W-20. I feel a lot safer with it and it doesn't cost more. In the hot summer time, I actually use 10W-30.