Why don't we all use 5w-50?

[armypa]

With all the advantages of synthetic oil, why is it made in so many viscosities? If it is made in 10w-30 and 5w-50, then why don't we all use 5w-50? Please explain.

Thanks,
Chris

[silverstreakin]

depends on the temp where you live

[EKam]

Yea Summer tires also made in different sizes why can't you get bigger tires without upsizing your rims??

Same theory.

You engine is only made to use one viscosity type unless you race it everyday at the track.

[armypa]

If 5w-50 spans a greater temperature range then 10w-30, then it can be used in BOTH a colder and warmer climate than 10w-30 can. This would give the best protection regardless of climate. Hence my original question...

[brink]

At one point I was told that a blended oil breaks down more easily than a single weight oil. That's why people use straight 30w or such in tractors and combines... cause they sit for long periods of time unused during the winte,r a 10w30 would break down more than, say, a 40w

[csaxon]

armypa, the reason is oil pressure and seal pressure strength. The lower viscosity is used now because the engine tolerances are tighter and have to get lubricateion quicker to prevent damage. Toyota engine crank and valve seals are not designed to take the pressure that a 50 viscosity grade oil at high engine speed exserts. Nor would a 50 weight reach critical lubrication spots as quickly as a 5 weight. The results are leaking engine seals or complete blow out. Another example is pressure bleeding the brakes. Toyota seals in the brake system are limited to 14.5 psi with DOT 3 fluid when pressure bleeding or else the seals start to leak or blow out.

[armypa]

I understand what you mean csaxon. So I am not doing my engine any favors if I run 5w-30 in my Camry? If so, what blend and weight of oil do you recommend I use? I live in the rainy Pacific Northwest.

Thanks,
Chris

[csaxon]

armypa, I think you meant 5w50 in your last post. Toyota highly recommends 5w30 for all conditions. I would suggest that. If you find that you have some blow-by and are using more oil than usual then try a 10w30. DO NOT USE a 50w oil because you could actually damage your engine.

[armypa]

Thanks for that intelligent and informative information. It's a relief to get a response from someone on here who knows what he is talking about and doesn't post ridiculous pictures of pink bunnies. I'll change my oil to 5w-30 tomorrow.

-Chris

[brink]

Originally posted by armypa
It's a relief to get a response from someone on here who knows what he is talking about and doesn't post ridiculous pictures of pink bunnies. I'll change my oil to 5w-30 tomorrow.

-Chris

If you're referring to silverstreakin, that's his sig, dude.

[crazy_camry]

i've just read this thread and found it extremely funny...that is all