Oil Change in 2008 Prius now 5W20?...

"Dealer" does not equal "Toyota". Maybe that dealer has too much 5W20 in stock and they want to get rid of it. But users here do report that 5W20 seems to work fine in cold weather.

 

AFAICT, Toyota has not changed the oil weight recommendation for the 2004-2009 Prius.

Your dealer is possibly misreading a TSB, or is blurring the truth to save some money (I think many have changed their bulk system to 5w20).

http://priuschat.com/forums/gen-ii-...62-toyota-now-recommends-5w-20-most-cars.html

The above link indicates that 5w-30 should still be used for Gen II Prius. However someone working at a dealer claims Toyota has authorized 5w-20 in Gen II Prius, but does not provide any citation.

http://priuschat.com/forums/gen-iii...leshooting/62662-oil-change-8.html#post918486

 

AFAIK the GenII Prius still requires a 5W-30. I checked at All Data, there is no TSB suggesting a 5W-20 on the 2004-2009 Prius. There is a TSB from 2007, stating a 5W-30 must be used

I used Mobil 1 0W-20 in my 2004 Prius, with good results. I also followed up with used oil analysis to verify everything was ok

Some vehicles on the 5W-20 list, such as my FJ Cruiser, probably should not be on the list. I had very bad used oil analysis results running xW-20 in that motor. It also made a lot of valvetrain ticking noises on xW-20

With the FJ, running Mobil 1 European Car Formula 0W-40, much better lab reports and the motor is quiet. Oddly enough, there was no difference whatsoever in fuel economy

With my Prius, there was no difference in summer fuel economy running 0W-20. In winter, perhaps 2-4 mpg more

 

I used Mobil 1 for years, perhaps 10 or 20 years ago they were the best, now I've made the switch to Pennzoil Platinum. (pennzoil conventional may be garbage, but their synthetic is I think the best avail)

here's a hint: synthetic oil + toyota filter ($7 at dealership) = 11K miles coverage
synthetic oil + Fram Extended Guard filter ($8 at walmart) = 15K miles coverage

 

Im on my second oil change at 30k!!!
First one was at 10k which was pushing it with stock oil.. :deadhorse:

Luckily my last change was with Mobil 1 Synthetic 0W-20 with Mobil 1 Filter. lane:

I just go by my experience with Mobil 1 Synthetic.. it last a long time. :bounce:

Oh yes, and I recommended a drop-in KN Filter just for the fact that its re-useable.


And YES my prius is a rules!! :rockon:

 

That may sound horrifying, but consider the same Prius sold in the EU will have its first scheduled service also at 10,000 miles. For cars sold in the EU, there is generally no early initial service