Mazda Moly Oil in 5W-30: Does It Even Exist?

Costco Kirkland signature 5w30 full synthetic is GF6 SP Dexos gen 2 sold as (2) 5 quart jugs in a box for $25 and has a high moly dose as well. Just used it as first change after 2500 miles. Best stuff at crazy cheap price
80 is not high moly dose. 600 ~ 700 is the usual number from the UOA of Mazda 0W-20 moly oil.

PQIA Kirkland 5W-30 synthetic - Bob Is The Oil Guy

And some Kirkland Signature 5W-30 jugs (old batch?) still say SN / GF-5.
 
For 2021 CX-5, Mazda doesn’t say Castrol® as one of the recommended engine oils in owner’s manual like it used to be. Between the 2 oils you listed, I personally prefer Castrol Edge 5W-30 full synthetic oil.

Here’s oil recommendation on 2021 CX-5 2.5T for USA and Canada:

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And here’s oil recommendation on 2021 CX-5 2.5T for areas other than USA and Canada:

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But I agree with dunhillmc. If I had a 2.5T, Idemitsu SP / GF-6 5W-30 oil would be my top choice.

I just noticed.. NOT Synthetic oil. I wonder if it's ok to put full synthetics
 
I just noticed.. NOT Synthetic oil. I wonder if it's ok to put full synthetics
People should definitely use full synthetic oil on any turbo engines due to extremely high temperature on turbo charger, and the car manufactures don’t offer any cool-down advice such as idling the engine for a minute before the engine shutdown. Full synthetic oil offers much better extreme high and low temperature protection like sm1ke mentioned above.

Since Mazda recommends 5W-30 oil for the 2.5T, be aware there’re plenty of conventional 5W-30 oils on the market, including OEM Mazda genuine 5W-30 oil. Avoid these oils and make sure you use the oil says “Full Synthetic” on your 2.5T.

Even better, use newer GF-6 oil such as Idemitsu SP/GF-6 5W-30 oil for timing chain wear protection、better fuel economy and engine sludge protection、and more.

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People should definitely use full synthetic oil on any turbo engines due to extremely high temperature on turbo charger, and the car manufactures don’t offer any cool-down advice such as idling the engine for a minute before the engine shutdown. Full synthetic oil offers much better extreme high and low temperature protection like sm1ke mentioned above.

Since Mazda recommends 5W-30 oil for the 2.5T, be aware there’re plenty of conventional 5W-30 oils on the market, including OEM Mazda genuine 5W-30 oil. Avoid these oils and make sure you use the oil says “Full Synthetic” on your 2.5T.

Even better, use newer GF-6 oil such as Idemitsu SP/GF-6 5W-30 oil for timing chain wear protection、better fuel economy and engine sludge protection、and more.

View attachment 301105

As someone who plans to own my CX-5 long term (It is 8 years old now at almost 103k miles), I absolutely plan to switch to this GF-6 oil in 5w30.

Saw a 350k CX-5 on the CX-5 facebook page the other day. Have seen others at 250k+. Looking forward to seeing mine go that long. I am not believer in buying new vehicles every few years.
 
People should definitely use full synthetic oil on any turbo engines due to extremely high temperature on turbo charger, and the car manufactures don’t offer any cool-down advice such as idling the engine for a minute before the engine shutdown.

Wait.. I thought that wasn’t necessary on modern vehicles!
 
Wait.. I thought that wasn’t necessary on modern vehicles!
If you’re referring to the idling before the engine shutdown on turbo engines, you’ll need to check the design of the different turbos. Some will do delayed oil or coolant circulation automatically without you knowing, others may just do nothing. Since the temperature on turbo is so high, sometimes the conventional oil in there gets cooked and will develop sludge problem in the long run. Synthetic oil definitely will have less chance to get cooked, and less prone to develop the sludge.

I personally don’t buy any cars with turbo, but have seen many turbo owners still keep the old habit to slow down the engine from a high-speed drive, and idle a bit then shut down the engine.
 
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Wait.. I thought that wasn’t necessary on modern vehicles!


It is buried in the manual, but it's mostly just there so Mazda is protected. The turbochargers in most modern cars are efficient enough that this is less of an issue than it used to be. Plus, I think it's rare that someone would actually turn the car off immediately after some hard driving - most people will exit off of a highway and drive normally before they park and shut down. The "driving normally" part is usually enough time to let the turbo cool down enough so that you don't have to sit and idle for a while.
 
Reminds me of a friend in college in '87 that had a Renault Fuego Turbo. That car was torquey and would catch decent rubber in 2nd gear. He told me his sister turned it off suddenly without cooling down the turbo after some hard highway driving and damaged the turbo. Funny how mundane 34 year old memories are still fresh.
 
Just got my oil changed at the dealer and it was for a full synthetic. They used Mazda OEM oil, part number:

0000-78-5W30-BK “Mazda 5W-30 Engine Oil GF”​


I can’t find any information that this is fully synthetic oil. Can anyone chime in?

I assume the GF is an indication?

The more I am researching this, the more it indicates that it replaces "0000-77-5W30-BKB", which was "super premium" oil. Not sure what I actually got.
 
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Just got my oil changed at the dealer and it was for a full synthetic. They used Mazda OEM oil, part number:

0000-78-5W30-BK “Mazda 5W-30 Engine Oil GF”​


I can’t find any information that this is fully synthetic oil. Can anyone chime in?

I assume the GF is an indication?
OEM https://www.amazon.com/dp/ (commissions earned) is the same as Castrol GTX which is NOT full synthetic, and it's also a GF-4 oil in quart bottle (QT).

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0000-78-5W30-BK replaces 0000-77-5W30-BK (BK = Bulk?) and there’s not much info we can find.

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Just hope 0000-78-5W30-BK is full synthetic.
 
I’m waiting to get info from my dealership. Service advisor called me and claimed “parts confirmed it is full synthetic”.

I am waiting for them to send me proof. If not, I’ll take it back. Last year they used Ford’s 5w30 full synthetic (GF6) because Mazda didn’t have that weight oil in full synthetic.
 
I just bought this at Wallyworld....$25
It was on rollback. The Mobil 1 EP wasc$28.
It's SP+ /6

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Confirmed with parts manager. It is not full synthetic. I am heading back to the dealership now.

They are replacing the filter again and putting in proper fully synthetic oil. Annoying but they will fix it.
 
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They will replace the filter again and put in proper fully synthetic oil. Annoying but they will fix it.

Funny how they tell you they’ll put the synthetic 5W-30 when there’s no such synthetic OEM 5W-30 from Mazda and you being unaware of course you get caugh in such $$$ lie. They did that to me till I found out here and discovered Idemitsu.
 
Yup. They’re giving me 2 free oil changes and threw in one for my wife. They’re lead tech was misinformed. The parts manager corrected everyone. I’m not pleased, but their response to the situation was adequate.

I’m curious what they do for every other 2.5T they do oil changes on. They probably use the GF4 oil they’re taking out of my car.
 
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