Using GF-7A instead of GF-7B...

[phantomxj]

Greetings, everyone.

I came here asking a question because I emailed a number of other sources but got no answer back.

I am from Iraq and I own a Chinese-spec Toyota Corolla Hybrid with 8ZR engine. This engine is basically the same as the 2ZR engine. In the summer here, it can get really hot, reaching 50°C (122°F), and I drive about 4,000km (about 2,500mi) every month, which includes a lot of uphill driving.

I am currently using 0w-16 oil but I want to switch to 0w-20. In the manual, it does mwntion that I can use a thicker oil for more protection for these extreme driving conditions... but I noticed that all viscosities higher than 0w-16 are GF-7A while the original viscosity recommended to me is GF-7B. I am curious because I read that this B classification was made for engine with very tight clearances and this got me concerned. Will a GF-7A oil liks 0w-20 cause long-term damage?

 

[phantomxj]

If I live in the Middle East with ambient temps of 50°C (122°F) I would definitely run 0W-30 or 5W-30 oil.
What is the lowest temp in your region?

It can go as low as 0°C or possibly a couple of degrees below that in the winter.

Should I go for 0W-30? And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

 

[dippschtick]

It can go as low as 0°C or possibly a couple of degrees below that in the winter.

Should I go for 0W-30? And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

 

[ZeeOSix]

It can go as low as 0°C or possibly a couple of degrees below that in the winter. Should I go for 0W-30?

A 5W should be good down to -30C.

And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

No need to flush the engine. Just drain it well and install the new oil and filter.

 

[Japanese]

It can go as low as 0°C or possibly a couple of degrees below that in the winter.

Should I go for 0W-30? And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

Yes, go to 0W-30 or 5W-30 full synthetic. Don't need to do anything to get rid of tge 0W-16.
Just change the oil every 5000 km if you use mineral oil or every 8000 km if you run full synthetic. Preferably use full synthetic oil.

 

[phantomxj]

C'mon, this is like the "yes" meme. to which question? All of them? Lol

 

[phantomxj]

Yes, go to 0W-30 or 5W-30 full synthetic. Don't need to do anything to get rid of tge 0W-16.
Just change the oil every 5000 km if you use mineral oil or every 8000 km if you run full synthetic. Preferably use full synthetic oil.

I always (which means just two times since this will be the third oil change) use full synthetic.

 

[Durdude]

Valvoline Restore and Protect 0w-20. Or 5W-30 in summer? Only way to tell whats best is with a UOA perhaps after running a weight a couple times?

 

[Durdude]

It can go as low as 0°C or possibly a couple of degrees below that in the winter.

Should I go for 0W-30? And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

They can mix just fine. No flush needed.

 

[phantomxj]

Restoreband Protect 0w-20. Or 5W-30 in summer? Only way to tell whats best is with a UOA perhaps after running a weight a couple times?

The engine is new, only about 27,000km so far, and it is a hybrid, so not all of that was with the engine running. As for the oil tests, I don't think they are available here in Iraq but I'm not sure.

 

[dippschtick]

C'mon, this is like the "yes" meme. to which question? All of them? Lol

If you look closely you'll see what I highlighted. Thumbs up to the 0w30.

 

[Hohn]

It can go as low as 0°C or possibly a couple of degrees below that in the winter.

Should I go for 0W-30? And should I just replace the oil like normal or do something like an engine flush? To get rid of all traces of 0W-16? I don't know if different oil viscosities should mix or not.

You can safely use a 0w-30 in your car but you probably do not "need" to do so.

Don't mess with an engine flush. Just do a short interval oil change if you wish. Viscosities can mix harmlessly. What cannot always mix harmlessly are formulations. This is why it's important to sort of stick with an oil chemistry and constantly switching oil formulas isn't wise.

Personally if I were in your situation, I would choose a 20 or 30 grade either one based on what I had available that was the most resistance to oxidation. The "ideal" is probably a VW 508.00/509.00 20 grade oil, as that's arguably the strictest spec for a 20 grade.

But if the only way to get an oil with a robust oxidation-resistance spec is to go up to 30 or 40 grade, I would do so. You can't really go "too thick" on KV100 grade, and I'd go as thick as necessary to get robust oxidation resistance.

IN theory, a thicker 30 or 40 grade will cause the engine to run slightly hotter in hot weather. But this is more than offset by a more robust spec that requires oxidation robustness.

IN the USA, we would look for Mobil 1 ESP X2 0w20 or 0w-30 ESP.

 

[phantomxj]

If you look closely you'll see what I highlighted. Thumbs up to the 0w30.

I just noticed the highlighted part, sorry about that.

 

[phantomxj]

A

You can safely use a 0w-30 in your car but you probably do not "need" to do so.

Don't mess with an engine flush. Just do a short interval oil change if you wish. Viscosities can mix harmlessly. What cannot always mix harmlessly are formulations. This is why it's important to sort of stick with an oil chemistry and constantly switching oil formulas isn't wise.

Personally if I were in your situation, I would choose a 20 or 30 grade either one based on what I had available that was the most resistance to oxidation. The "ideal" is probably a VW 508.00/509.00 20 grade oil, as that's arguably the strictest spec for a 20 grade.

But if the only way to get an oil with a robust oxidation-resistance spec is to go up to 30 or 40 grade, I would do so. You can't really go "too thick" on KV100 grade, and I'd go as thick as necessary to get robust oxidation resistance.

IN theory, a thicker 30 or 40 grade will cause the engine to run slightly hotter in hot weather. But this is more than offset by a more robust spec that requires oxidation robustness.

IN the USA, we would look for Mobil 1 ESP X2 0w20 or 0w-30 ESP.

I am currently using Liqui Moly Special Tec AA 0W-16. Should I switch to Liqui Moly Top Tec 6200? It came up as compatible with VW 508.00/509.00 oil, and I think it is available and by using it, I'll stick to whatever formulas Liqui Moly uses. Their Special Tec AA is fine so far.

 

[kschachn]

A

I am currently using Liqui Moly Special Tec AA 0W-16. Should I switch to Liqui Moly Top Tec 6200? It came up as compatible with VW 508.00/509.00 oil, and I think it is available and by using it, I'll stick to whatever formulas Liqui Moly uses. Their Special Tec AA is fine so far.

You’re really keeping this thread alive.

 

[phantomxj]

You’re really keeping this thread alive.

Lol came here to know if it's safe to use GF-7A instead of 7B, now I'm here... it's a rabbit hole.

 

[dippschtick]

I just noticed the highlighted part, sorry about that.

 

[Mainia]

You’re really keeping this thread alive.

I have a feeling there is a doubting Thomas drifting in ..........................

 

[kschachn]

Lol came here to know if it's safe to use GF-7A instead of 7B, now I'm here... it's a rabbit hole.

Looking back I think you got that answer a long time ago.

 

[phantomxj]

Looking back I think you got that answer a long time ago.

Yes, but then everyone kept reply with a new piece of information and... well, curiosity got the better of me.

 

[Durdude]

The engine is new, only about 27,000km so far, and it is a hybrid, so not all of that was with the engine running. As for the oil tests, I don't think they are available here in Iraq but I'm not sure.

Oh. A hybrid. I would probably run the 0w-20. Perhaps the engine does not run constant or long enough to get and hold a operating temp of over 210F to really warm the 5w30. Ow20 should be good restore protect .