5w-40 Rotella T6 in a Turbo Mazda

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first off, it's been a while since I've been on the forums, so forgive me if there's been any changes or strides that I'm unaware of.
To start off, I've always ran 10w-30 M1 on a 3-4k interval. If I extended it further my HLA's would tick very loudly on start up and noticeably louder than normal after warmed up. Well Since I've put a turbo on my car I've done 2 oil changes, both using M1 10w-30. On the first fill I got to 2,xxx and it started ticking. Well I thought the valve in the filter had failed. I used a Honda oil filter (honeywell) so I replaced that and it still ticked loudly.
Changed the oil and it went away. now after almost 3k its ticking loudly again, that change I decided to use a genuine Mazda oil filter.

I read some guys that run turbo miata's really like Rotella t6 so I decided to go out and buy a gallon. I think I'll go with a Honda filter again because I work at a Honda dealership so I get them for nothing. It is a little thicker oil but I can't see that hurting anything in my application.

here's the basic's
1. What kind of vehicle you have- Mazda Protege, 1.8 DOHC turbo
2. What your owner's manual says -- not just viscosity, but certifications (look for acronyms like API SM, ILSAC GF-4, etc.) and change intervals as well ---Not sure but it's not the stock motor so that irrelevant.
3. Where you live --South Florida
4. How you drive (easy? hard? fast? slow?) -- hard, lots of high RPM's
5. What your daily drive is like (short trips? long trips? city? highway?)--some short trips mixed with highway drives(note-5th gear, 80mph is ~4200rpm
6. Whether your car has any known problems-- a leak that needs to be addressed. nothing serious though.
here's some eye candy.
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What's not stock about the engine?
I don't see the need for such a heavy oil in a car that isn't tracked.
M1 0W-40 would be as heavy as I'd go.
A 50/50 mix of M1 0W-30 and 0W-40 would be preferred and still be heavier than the spec' oil including the M1 10W-30 you used to run.
 
Originally Posted By: CATERHAM
What's not stock about the engine?
I don't see the need for such a heavy oil in a car that isn't tracked.
M1 0W-40 would be as heavy as I'd go.
A 50/50 mix of M1 0W-30 and 0W-40 would be preferred and still be heavier than the spec' oil including the M1 10W-30 you used to run.

this car started life with a gutless SOHC. This is a Miata long block. It never came with a turbo on it. Once a month it sees 1/4 mile action and occasionally some Auto-x.
 
Drag racing and auto-x don't require heavy oil since the oil temp's are low.
The proper way to determine the correct oil viscosity is with an oil pressure gauge. Run the lightest oil that give you 70 psi at maximum rev's when the oil is as hot as it ever gets.
If you don't have an OP gauge then I'd go with the M1 mix I suggested. This will give you a heavy, high VI 0W-30 oil.
Two other oil options would be Pennzoil Ultra Euro L 5W-30 and Lucas 0W-30.
 
I would also pick M1 0w40 over RT6 for a gasoline turbo engine.

I'm not familiar with the DOHC Miata engine. Does it have mechanical or hydraulic lash adjustment in the valvetrain? Assuming it's hydraulic, maybe one of the lash adjusters is sticking. A high detergent oil may clear that up over time, and RT6 may help with that since it is formulated for dispersing large amounts of soot in modern diesels. But I wouldn't run more than one or two change intervals with it.

M1 5w30 may be a good choice, as it meets Honda's HTO-06 spec for turbocharged engines.

Red Line 5w30 would be an excellent choice if you don't mind the extra cost and low availability. But since you have a lot of time and money invested in building the car, you seem to me to be the type of enthusiast that would go for it.
 
Originally Posted By: A_Harman

M1 5w30 may be a good choice, as it meets Honda's HTO-06 spec for turbocharged engines.

That being the case, or any other oil that meets Honda's HTO-06 spec', then all other choices including M1 0W-40 and RL 5W-30 would be OTT heavy and I suspect they likely are.
 
Originally Posted By: CATERHAM
Originally Posted By: A_Harman

M1 5w30 may be a good choice, as it meets Honda's HTO-06 spec for turbocharged engines.

That being the case, or any other oil that meets Honda's HTO-06 spec', then all other choices including M1 0W-40 and RL 5W-30 would be OTT heavy and I suspect they likely are.

harman- yes it does have Hydraulic lash adjusters. It's not stuck, they just get noisy when the oil gets sheared down. M1 just isn't holding up, 10w-30 at least. I'm not so canny on trying different weights after it has disappointed me in the past.

catterham- OTT? I'm sorry, I'm not familiar with that abbreviation.
 
Hydraulic lash adjusters can get noisy for a number of reasons.
It's often related to air entrainment and some oils are better in certain applications than others regardless of the oil's viscosity.
I've had the problem even with 40 and 50wt oil and finally acheived perfect silence with 0W-20 oil. But I agree used oil seems to be more of a problem than fresh clean oil but I've found that that may be related more to air getting into the oil when the oil level is lower but usually has little to do with oil shear. For example the low VI M1 10W-30 has little in it to shear.

OTT - Over the Top.
 
Nothing wrong with using T6, though I agree it might be a bit heavy for that motor.

Pennzoil Platinum also meets/exceeds HTO-06.
 
The Miata motors are known to tick anyway don't they? We had 2 of them at the dealer where I worked and we decided to give something a try. We changed the oil in one with 10w40 and the other with 0W30. They both still sounded like sewing machines. But in the end those engines seem to run forever anyway. See if the T6 changes this. It might be a bit thick for a motor that revs so high all the time. I think that is why everyone is telling you to go with something thinner. Not sure which spec it is but there is a spec that is supposed to handle foaming of the oil or handling air in the oil to keep things like VVT and cylinder deactivation working properly. It would probably be best to try an oil that meets as many specs as possible to see if it helps you any. Mobil1 and PP are prob the best choices as far as meeting specs. The 0W40 would give you thicker (if not much thicker) oil than using a 30wt if you want to see if thicker helps your problem. The T6 is much thicker IIRC. Please post back with your results, I am curious to see what changes if any it makes by using a different oil since we could not shut either of those Miatas up. Both of them are still going strong today even though they do still sound awful. Tough little engines.
 
yeah, this particular motor has never really been loud unless its low really. It's only started getting loud HLA's since I put on the turbo. You guys think the high temps combined with a rich tune are causing it? Obv, I'm running a rich tune on a turbo motor to protect it so I'm sure theres some fuel in it.
Here's a Trubo Miata UOA using T6. This car is HEAVILY tracked and sees 4k-7k for 5 hours at a time. It's supposed to be 1700 miles, not 700.
also,Doing the oil change tomorrow at work. I'll record a before and after video for you guys too.
54yx38.jpg
 
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Originally Posted By: CATERHAM
......................
A 50/50 mix of M1 0W-30 and 0W-40 would be preferred and still be heavier than the spec' oil including the M1 10W-30 you used to run.


Do the M1 0W-30 and 0W-40 have identical additive packages? Seems to me that this blend (or any blend for that matter) undoes the additive formulation expertise that went into the product.
 
The Honda filter is a Blue Fram with cardboard endcaps. My local Honda dealer has one in a display that I laugh at each time I come in. Find something better.
 
Originally Posted By: SubLGT
Originally Posted By: CATERHAM
......................
A 50/50 mix of M1 0W-30 and 0W-40 would be preferred and still be heavier than the spec' oil including the M1 10W-30 you used to run.


Do the M1 0W-30 and 0W-40 have identical additive packages? Seems to me that this blend (or any blend for that matter) undoes the additive formulation expertise that went into the product.


Why not just go with the 0W-30 on this one? Although, since i went the mix route myself (between xW20 and xW30,) that doesnt sound all too illogical.

Additives aside, it is still M1.
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Originally Posted By: CATERHAM
What's not stock about the engine?
I don't see the need for such a heavy oil in a car that isn't tracked.
M1 0W-40 would be as heavy as I'd go.
A 50/50 mix of M1 0W-30 and 0W-40 would be preferred and still be heavier than the spec' oil including the M1 10W-30 you used to run.


OP you could also use that 100%.. and if your engine doesnt otherwise reject it (no leaks, no other undesired effects) you are GTG to high RPM away!
smile.gif
 
So the fuel dilution is your problem too? Get the hand pump and some vinyl tubing that fits the dipstick tube. Replace 1 quart of oil every 2 weeks.

I have seen synthetic 15w-40 Royal Purple at Oreillys. But I don't know if it's for gasoline engines. Wouldn't that be more resistant to fuel dilution than 5w-40?
 
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