XXX

 

My engine just crossed 50k and I'm due for an oil change. I've read this thread many times but I don't see any real debate or information here about viscosity choices, rather than just brands. If you read the manual for my 02 WRX, it has a surprisingly large range of suggestions for viscosity; it seems to say "use 5W30" but then also suggest 10W30 for high-heat use and 10W40, 10W50 and up to 20W-50 in some situations. Currently I use Castrol Syntec 5W30; is it time to switch to a thicker oil, to make up for the internal engine wear normal to an engine of that age? Should I run 5W30 in the winter and 10W40 in the summer?

 

If you aren't burning/using more oil than you used to, I would say stick to what you are using. If your oil consumption starts to creep up, then I would say go to a 10w30 or 1w40. Actually, given the heat where you live, I would run 10w30 year round unless your overnight temps get below 50 often in the winter, then 5w30 might still be best.

 

Yeah,
I have had GREAT luck just running the 5/30. Only now, with 140,00 miles on the clock am I starting to run the thicker stuff. You wouldn't catch me putting conventional oil in a motor these days, however. The consistency/insurance is MORE than worth the extra expense!

 

kevin from AutoHQ has convinced me to go to the thick stuff... so i'll be using 5w-50 for my oil change this weekend.

 

Unless you spend an awful lot of time on the track and very little time warming up/idling in cool temperatures, that's too thick... but that's just my opinion. You would do just fine with good synthetic 10w30 like everyone else that isn't literally driving a race car.

 

hows that? isnt it bad for pressure and seals?

 

Um how do you change tranny oil ? i don't think i have done that in a long time