Synthetic Castrol Magnatec 5W-30 into F20B6 engine

[dandreye]

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 Castrol Magnatec 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. There's a good offer on the 5W-30 in question at Tesco 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 zone and points downwards, extending below -30C, as if this oil is targeted mainly for winter. My worry is whether it becomes too thin on hot summer days 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!

 

[MedicalFlyer]

Sticking my reg in to Castrol's Oil selector brings up Edge 5w-40 or Magnatech 5w-30 A5 so you should be good to go.

Mine's a 2000 F20B6 with about 91k on it and I use Shell's recommend flavour of Helix HX7.
My dad's car is a 1998 F20B6 with about 137k and he uses all sorts in it and never had any problems.

As long as the engine isn't dribbling anywhere you should be fine. These are tough old lumps and providing the oil is regularly changed you shouldn't have any worries at all.

 

[dandreye]

MedicalFlyer:

Thanks for your reply: I actually bought a few of those 4L ones this morning anyway (btw they turned out to be A5) and will then buy a few more shortly. The engine doesn't seem to be dribbling any oil at all - it rather consumes some of it, which is probably expected for its mileage. Regarding durability of these cars/engines I'm hearing from friends that they're known to last ~250-300k miles or even more: basically people more often swap them as they just get bored not because of any issues. I'm doing just 10k miles lately, so it should last several more years unless I get bored myself earlier )

 

[exec]

Do not go by those oil recommends, they are just generic software. On older higher mileage car you should use thicker grade oil, 10/40 is the original recommended grade by Honda, failing that you can use 5/40w for fully synthetic, which is what I use, although I have only 88k on the clock, or you can use 10/50w. 5/30w is too thin, on an older high mileage engine you want thicker oil for more wear protection.

 

[dandreye]

exec:

Got it - thank you: in that case I suppose I can use already purchased 5W-30 at least in winter (had a few imperfect engine starts with 10W-40, likely because of its thickness on those cold days).

 

[Alans27]

You'd probably be ok with 5w30 but it'll probably burn a bit more quickly and it's not ideal really. TBH I don't think Magnatec is as good as people think. It's certainly nothing special.
I've put Valvoline maxlife semi synthetic 10w40 in mine which is made for higher mileage engines and it runs fine. Valvoline is very good oil, can't go wrong with it.

 

[Alans27]

That being said I looked it up on the castrol website the other day (which I should have done in the first place lol) and as you say it recommends a 5w30 ford spec. Think it's ford spec. Crap I can't remember! But yeah it's a 5w30 anyway.

Best thing to do is try it. Stick a 5w30 in and if it starts burning it rapidly then switch to 10w40 on the next change. If not then stick with it.
Valvoline do a max life version of the 5w30 ford spec which is aimed at higher mileage engines so you kind of get the best of both worlds with that oil.

 

[jsmith89]

I use 5w40 Shell Helix Ultra fully synthetic.