Hi All,

Is synthetic Castrol Magnatec 5W-30 a safe choice for a 1999 Honda Accord engine F20B6 reaching 180k miles? Been using part synthetic 10W-40 for about 15 years on all my cars so far (2x Toyota Avensis and now this Honda Accord) thinking it's a better all-year-round oil choice. We have a really good offer on the 5W-30 in question here in UK at the moment, which I'd like to take advantage of while it lasts.

The following page lists 5W-30 as recommended oil type for F20B6 referring specifically to my Honda make year besides a few others:
http://cararac.com/engine_oil/honda/accord.html
Engine Engine code Year Recommended oil How much (L.)
2.0 F20B6 2002 Synthetic 5w30 4.3
2.0 F20B6 2001 Synthetic 5w30 4.3
2.0 F20B6 2000 Synthetic 5w30 4.3
2.0 F20B6 1999 Synthetic 5w30 4.3

My Honda manual doesn't specifically say that any particular grade is better than the others - it just lists about 5 different ones and doesn't mention whether they're mineral, part synthetic or fully synthetic at all. The applicability arrow starts somewhere in 30-35C (85-95F) zone and points downwards, extending below -30C (-22F), as if this oil is targeted mainly for winter. We do occasionally have ambient temperature reaching 30-35C (85-95F) in summer, hence worrying if it becomes too thin on such days increasing engine wear. I do realise that with 180k miles behind the engine is unlikely to have too much resource left before its first overhaul but why shorten it any further )


Many thanks in advance!

 

I've run Mobil 1 synthetic since my first oil change 2009 V6. I run the recommended 5W-20 with summers averaging 80 everyday and warm days heading into the middle 80's. I'm no oil guru but supposedly synthetic really excels in cold and hot applications. I've got 100,000 miles and never plan on switching to a "high mileage" blend.

 

dgp1961:

Thank you: bought a number of 4L ones and will give them a try.