90-100deg temps, GC or 5w-40 for Miata.
- Thread starter JGmazda
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JG,
I think you have every reason to use a Zee-dub. If it is thinner at startup than the 15W-40 you might use then you are getting less startup wear, less drain on your battery, less drag on your starter. I cannot imagine why, unless a certain formulation proves susceptible to issues due to the viscosity range (like shearing or too much VI improver), everyone would not want to use a 0W-XX. To state once again what many of us have said before...if the oil is a 30W it is a full 30W at operating temps no matter what the xW starging point is. Recall that Porsche puts M1 0W-40 in as inital fill and as recommended refill in its engines, including those bound for the Sheiks in Saudi Arabia.
pscholte - Very good point! Now...(If this weren't enough questioning...
We all know "GC" has a unique base. And I know you are a huge proponent of GC. I know that at operating temps.... it is a "30" weight. But what about extreme temps? I know you even recommend this for a turbo. How good is "GC" at the high end of the scale? Does it use alot of VII? to reduce it's pour point?
JGm,
Because of our altitude in Der Schwarzwaldwesten (our house is just shy of 7000' and we are not even in the mountains) the turbos in our A6 are on boost more often than they would be at lower altitude. Therefore our oil temps are probably 10 - 15ºF (or more) hotter than in most of the cars on this board (I would be willing to bet that at times they match or exceed the oil temps of cars taken to the track). GC handles it admirably so I believe I can attest that at the extreme high end of the temp scale I have tested and proven GC. I cannot get specific because of the agreement surrounding the testing Terry Dyson did on GC for us, but trust me, you do not need to worry in the slightest about the amount of VII in GC.
Because of our altitude in Der Schwarzwaldwesten (our house is just shy of 7000' and we are not even in the mountains) the turbos in our A6 are on boost more often than they would be at lower altitude. Therefore our oil temps are probably 10 - 15ºF (or more) hotter than in most of the cars on this board (I would be willing to bet that at times they match or exceed the oil temps of cars taken to the track). GC handles it admirably so I believe I can attest that at the extreme high end of the temp scale I have tested and proven GC. I cannot get specific because of the agreement surrounding the testing Terry Dyson did on GC for us, but trust me, you do not need to worry in the slightest about the amount of VII in GC.
I like AMSOIL Series 3K. Still a 5W30 spec but with other neat stuff added to it.
pscholte- Thanks for all the info! You make a very convincing case going with GC. I'll give it a try in my car and do a UOA. (Which I've never done) Any suggestions or links for a UOA would be appreciated.
Thanks very much for helping in my "madness!"
Thanks very much for helping in my "madness!"
Hey JGmazda.........not to beat this one into the ground,but,sounds like you have"some" miles on your ride.........Does it burn oil? If so, couple of things ya might want to look at. Mabe the rings are a little carboned up, that will prevent a tight seal against the cyl. wall. Causing oil to push by the rings,forming carbon,losing abit of compression,messing up your cat. Then a HDEO will help clean your engine.Bumping your vis. will also help prevent oil burning.
New gen. 15/40 still has higher anti-oxidation inhibitors/anti wear properties than ANY oil.So it works harder and longer than a syn. or dino oil.in any vis.range or temp range.
New gen. 15/40 still has higher anti-oxidation inhibitors/anti wear properties than ANY oil.So it works harder and longer than a syn. or dino oil.in any vis.range or temp range.
I guess that means my 5W-40 Synpower idea was a complete waste of thread space.
GoldenRod ... Heck no! I'm going to give that a shot also. Do a UOA on it and decide. I appreciate your input and lots of people read things here and you never hear from them.
I think the answer is that we need to make educated choices... and everyone on this thread has made excellent choices. Now it's up to me to try an see what oil fits my car the best.
Thanks.
I think the answer is that we need to make educated choices... and everyone on this thread has made excellent choices. Now it's up to me to try an see what oil fits my car the best.
Thanks.
JGMazda
To my knowledge as far as I know if anything the fact that the oil is thinner than 10w-30 would cause less wear to your engine at startup and be of benefit to your engine. Feel free to jump in share and enlighten me if I'm wrong.
To my knowledge as far as I know if anything the fact that the oil is thinner than 10w-30 would cause less wear to your engine at startup and be of benefit to your engine. Feel free to jump in share and enlighten me if I'm wrong.
JimKJSVT ,
Maybe I'm wrong...? But I think the benefits of having having a "thicker" lube in my bearings and on the Cams when starting would be a benefit.
Additionally, The differance between 0w & 5w in starting up??? Maybe a 10w? I'm not sure if that's a factor here in Phoenix for most of the year. Do you think it is?
I like the idea that GC is a true synthetic. But I know my cars owners manual calls for 10w-30. That was back in 1994. Before that, same engine, called for 20w-40 and 20w-50 in the current temp ranges. (Pre CAFE Miata's)
Perhaps oil has gotten so good that there is no need for a 20w-50 any longer.
I've actually tried Castrol GTX 20w-50 and it was sluggish! Cold starts did sound good though! No HLA clatter which is a trademark of this particular 1.8L engine. GC made noise until the pressure built up. Other than that... My engine gets extrememly hot during traffic. Temp gauge gets warmer and you could barbecue in there. Aside from an Oil cooler.. (I don't know the actual temps involved) I feel an oil closer to a 40w would protect me better. Especially at lower RPM where you don't have the pressure.
I will go synthetic due to higher flashpoints. I plan on giving Synpower 5w-40 a shot based on Terry's comments. I won't use Mobil 1 for a variety of reasons.
Yes... I guess I'm just as "quirky" as alot of people on this board.
Maybe I'm wrong...? But I think the benefits of having having a "thicker" lube in my bearings and on the Cams when starting would be a benefit.
Additionally, The differance between 0w & 5w in starting up??? Maybe a 10w? I'm not sure if that's a factor here in Phoenix for most of the year. Do you think it is?
I like the idea that GC is a true synthetic. But I know my cars owners manual calls for 10w-30. That was back in 1994. Before that, same engine, called for 20w-40 and 20w-50 in the current temp ranges. (Pre CAFE Miata's)
Perhaps oil has gotten so good that there is no need for a 20w-50 any longer.
I've actually tried Castrol GTX 20w-50 and it was sluggish! Cold starts did sound good though! No HLA clatter which is a trademark of this particular 1.8L engine. GC made noise until the pressure built up. Other than that... My engine gets extrememly hot during traffic. Temp gauge gets warmer and you could barbecue in there. Aside from an Oil cooler.. (I don't know the actual temps involved) I feel an oil closer to a 40w would protect me better. Especially at lower RPM where you don't have the pressure.
I will go synthetic due to higher flashpoints. I plan on giving Synpower 5w-40 a shot based on Terry's comments. I won't use Mobil 1 for a variety of reasons.
Yes... I guess I'm just as "quirky" as alot of people on this board.
Are you saying you've already tried GC? In what vehicle? the Miata? Anybody else want to weigh in on the best startup viscosity?
Any oil you run, whether 20W-50, 15W-40, 5W-30, 0W-30 or 0W-20, will be too thick at startup. An ideal oil would have the same viscosity at startup as it would at operating temperature. When thinking about GC, completely forget about the 0W. The 0W actually makes GC a better choice.
Don't worry about GC not being robust enough for high temperatures. It has the ACEA A3 rating, which is a tough one to get. In order to get the A3 rating, an oil must have an HT/HS rating of at least 3.5. You'll notice that most Mobil 1 grades don't have it, becuase they are thinner. Bottom line, A3 oils can take a real beating.
In addition to ACEA A3, GC has the ACEA B3/B4 rating, and all sorts of stringent manufacturer certifications that people who own german cars can tell you about.
JimKJSVT ,
Yes. I have tried GC in my Miata. I liked that it didn't seem to make quite the noise Mobil-1 did when I drove hard. It did not fix the typical Miata HLA noise on startup though. That's what made me believe it's very thin at startup.
I had used 10-40 dino a few months before and there was zero HLA clatter when starting up. I had hoped that GC would fix that issue.
Seems my car likes a "thicker" oil for some reason?
I understand these cars have minds of their own when it comes to oil. Some do better on thin or thick oils.
I've checked with many Miata owners and they said every car has it's own oil "comfort" zone. So this is why I've been asking around. I've been told to try a HDEO like a 15w-40 or stick with Dino 10w-40.
I want to use a synthetic because I'd like to push my OCI's to about 5k. GC was much better than Mobil 1 by my seat-of-the-pants meter.
However...
My next run I plan On trying some Synpower 5w-40.
Palut--- Thanks for the info too! I sure wish Castrol would make a 10w-30 "GC". I can't get over the fact that a 0w oil is the best choice for my car. Yes... I know it's close to 12cst. (40 weight). For my car, Mobil oils were way too thin.
Yes. I have tried GC in my Miata. I liked that it didn't seem to make quite the noise Mobil-1 did when I drove hard. It did not fix the typical Miata HLA noise on startup though. That's what made me believe it's very thin at startup.
I had used 10-40 dino a few months before and there was zero HLA clatter when starting up. I had hoped that GC would fix that issue.
Seems my car likes a "thicker" oil for some reason?
I understand these cars have minds of their own when it comes to oil. Some do better on thin or thick oils.
I've checked with many Miata owners and they said every car has it's own oil "comfort" zone. So this is why I've been asking around. I've been told to try a HDEO like a 15w-40 or stick with Dino 10w-40.
I want to use a synthetic because I'd like to push my OCI's to about 5k. GC was much better than Mobil 1 by my seat-of-the-pants meter.
However...
My next run I plan On trying some Synpower 5w-40.
Palut--- Thanks for the info too! I sure wish Castrol would make a 10w-30 "GC". I can't get over the fact that a 0w oil is the best choice for my car. Yes... I know it's close to 12cst. (40 weight). For my car, Mobil oils were way too thin.
There is a UOA of ZoomZoom's Mazda V6-KL engine with GC 0w-30 and it did pretty good. I would tend to think in Phoenix 10w30 would be preferred over 5w30 if you are going dino though, but I also feel certain if you go to the dealer for an oil change you will come away with 5w30 (motorcraft).
Going heavier than XXw40 may give you more of a heat problem as the oil can not flow fast enough, cool fast enough, and creates more drag thus heat on the engine. In most of the Japanese built Mazda engines, you should be able to safely use up to a XXw40 though.
My Mazda manual says i can use 5w30 or 10w30 over large temp ranges. I've used both and can't seem to tell a difference. It does seem to "like" Motorcraft 5w30 oil though. I'm not sure if that's psychological or factual, or because thats what it was broken in with. At idle with 5w30 the engine is perfect sounding. With 10w30 there is a tiny hint of a "drone" when using 10w30 that i could only guess is a ever so slight drag on the pistons and/or oil pump.
Then again, there may be more of a viscosity difference between different makers of different 5w30's than there is between 5w30 and 10w30 of the same maker.
I'm rambling.... time for bed
Going heavier than XXw40 may give you more of a heat problem as the oil can not flow fast enough, cool fast enough, and creates more drag thus heat on the engine. In most of the Japanese built Mazda engines, you should be able to safely use up to a XXw40 though.
My Mazda manual says i can use 5w30 or 10w30 over large temp ranges. I've used both and can't seem to tell a difference. It does seem to "like" Motorcraft 5w30 oil though. I'm not sure if that's psychological or factual, or because thats what it was broken in with. At idle with 5w30 the engine is perfect sounding. With 10w30 there is a tiny hint of a "drone" when using 10w30 that i could only guess is a ever so slight drag on the pistons and/or oil pump.
Then again, there may be more of a viscosity difference between different makers of different 5w30's than there is between 5w30 and 10w30 of the same maker.
I'm rambling.... time for bed
hominid7 -
These cars (Miata's) seem to last forever engine-wise. I've never had a car that had "normal" HLA noise on startup though. It does not hurt anything. I wonder if the Dino oil it was raised on kept the HLA's pumped up better?
Whatever the reasons, I feel the car does better from many standpoints with the thicker oils. Especially in 100deg temps. Some of you will say there won't be a differance, but....
I just know that Mobil 1 made me think I was running water after a high speed run in the heat.
Maybe it still protected my engine...? It just sounds (and feels) terrible. BTW, 10w30 is the recommended choice in the manual.
Australians down under will probally tell you they use a 20w-40 0r 50 in their Mazdas. Hmmmmmmmm.....
These cars (Miata's) seem to last forever engine-wise. I've never had a car that had "normal" HLA noise on startup though. It does not hurt anything. I wonder if the Dino oil it was raised on kept the HLA's pumped up better?
Whatever the reasons, I feel the car does better from many standpoints with the thicker oils. Especially in 100deg temps. Some of you will say there won't be a differance, but....
I just know that Mobil 1 made me think I was running water after a high speed run in the heat.
Maybe it still protected my engine...? It just sounds (and feels) terrible. BTW, 10w30 is the recommended choice in the manual.
Australians down under will probally tell you they use a 20w-40 0r 50 in their Mazdas. Hmmmmmmmm.....
Think of it this way. You seem to want an oil in the range of 12-15 cst at 212°F. GC fits that bill.
Based on this thread, GC at 104°F (40°C) is 54 cst. That's 450% of the viscosity you want, and that's if you start the car at 104°! It's DEFINITELY not too thin at startup. It's 4.5 times too thick!
It's been established that even with a 30 point viscosity spread, GC is still a shear stable oil. Don't worry about the 0W rating. It means that you're getting an oil that's very robust at high temperatures yet causes less wear at startup.
A 5W-40 sounds like a fantastic option too. I just don't want to see you base a decision on a misconception.
EDIT: Just looked around some more, and I was probably wrong about the GC viscosity at 40°C. It's higher than 54, more like 70. That just proves my point a little more.
Palut-
Thanks very much for the info! I know... It's just me being old school. I plan on giving GC another try after I give the 5w-40 Synpower a shot.
Based on your comments, I will try it again. I hope the Synpower is better than Mobil 1. I supposedly could mix my own brew of Mobil 1 (15w-50 & 5w-30 ) but what's the point? I have little knowledge what that viscosity would be.
Shear stable is a priority here.
I'd like to find the oil and stick with it! Car is going on 110K and I hope to have it go past 200k.
Thanks for taking the time to reply!
Thanks very much for the info! I know... It's just me being old school. I plan on giving GC another try after I give the 5w-40 Synpower a shot.
Based on your comments, I will try it again. I hope the Synpower is better than Mobil 1. I supposedly could mix my own brew of Mobil 1 (15w-50 & 5w-30 ) but what's the point? I have little knowledge what that viscosity would be.
Shear stable is a priority here.
I'd like to find the oil and stick with it! Car is going on 110K and I hope to have it go past 200k.
Thanks for taking the time to reply!
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