Advice wanted for new Mazda3 2.5 non-turbo

Even though the car is a manual transmission, it does have Cylinder Deactivation. I will go with spraying Corrosion X since that is what I have on hand. Used it on my old car, which showed no signs of rust despite ten winters.
 
I wouldn't mess with any underbody finishes except for fluid film, Krown type sprays.
Messing with an underbody finish... I agree with your comment on the underbody proper... but as to the subframe and suspension steel-pressing/welded members... I WOULD agree with you if Mazda actually put any sort of finish on said cpts! As it is, their finish on said cpts (which are not galvanized) is really, really poor, but what's more is that their propensity to corrode is very high. That's why I say scrub-up, red oxide primer, two top-coats of industrial alkyd. Then, for impossible to reach boxed-in areas of the steel fabrications, yes, high-creeping waxy cavity sealer...
 
OP - Good luck with car, sounds like a nice one.
My limited experience with new Mazdas to my family seem to show high moly in their oil and the undercoating a good idea. The first OCI is a dilemma. Virgin oil analyses show Mazda oil contained Manganese - a scuffing agent. High molybdenum content you can find in modern oils, but I haven’t seen shelf oil with any manganese. ( A good thing imho)
So an early dump of the ff might not work as well as hoped. If you can get Mazda data that is current, it might help you.
Honda used this procedure for a long time and they were adamant about NOT changing early.
Dont know how much this helps, but either way, enjoy the car. Earlier references to this choice were well said in this thread, so reread and let us know what new data you find.
 
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PS - for the record, I was an early and often oci guy for all new vehicles to the family.
300 miles, 1000 miles, and then every 3k, or 5k, or 10k depending on the vehicle, use, and driver.
 
OP - Good luck with car, sounds like a nice one.
My limited experience with new Mazdas to my family seem to show high moly in their oil and the undercoating a good idea. The first OCI is a dilemma. Virgin oil analyses show Mazda oil contained Manganese - a scuffing agent. High molybdenum content you can find in modern oils, but I haven’t seen shelf oil with any manganese. ( A good thing imho)
So an early dump of the ff might not work as well as hoped. If you can get Mazda data that is current, it might help you.
Honda used this procedure for a long time and they were adamant about NOT changing early.
Dont know how much this helps, but either way, enjoy the car. Earlier references to this choice were well said in this thread, so reread and let us know what new data you find.


Where did you see this manganese in a VOA? I’d like to see that myself.
 
Greatly appreciate the advice. I see that the descriptions of both Amsoil break in oil and Royal Purple break in oil do not mention manganese, although both say ZDDP +.

Yes, I followed the Honda advice with my last car--did that stop the rings from getting carbonized? No.

Also the MM in the car seems to state first OCI is 5000. Manual in glove compartment not all that clear on oil requirements.
 
Manganese is not an oil additive in any form that I know of. Magnesium is used as a detergent additive along with calcium. Mazda oils have been noted for high amounts of molybdenum.


I am fortunate to have a nice long hill near the house so I put the CX5 in Sport Mode and get the RPMs up. Since you have a manual shift you can accomplish that easily on any road. These motors like to be wound up.
 
The UOA forum has factory fill samples and the manganese has been used in Mazdas, but very small amounts.
The one that really stuck with me was titled Mazda 0w20 W/Moly Oil, November 8, 2014.
After reading, it turns out the ff was on his Accord, explains the high Mn number. If you do find Manganese in a UOA, I would check your fuel source.
Enjoy the car, and if the MM says 5k, sleep well.
 
I've got a 22 CX5 with the 2.5 non turbo. I just did the 25k change last week, I change every 5k like clockwork and use Pennzoil Platinum 0w20 and a Mazda filter. No issues at all so far, the Mazda is the easiest I oil change I do by far. The filter and drain are both under 1 little cover and real easy to get to. Dump in a 5 quart jug after I am done and good to go for another 5k.
 
I appreciate the advice. Now the next big question-- premium, middle grade or regular? (not sure what the dealer filled the tank with.)

It’s likely regular from the dealer. Run that for a while and then run a couple of tanks of premium. You can determine which will work for you.

There has been some evidence that premium cuts down on fuel dilution. That’s an argument that will go back and forth here.

I run premium. I find that I get better response going up hills than with regular. That’s just my opinion.
 
These engines produce such little wear that even when you ride the factory OE fill out to 5k+ miles you still see low wear on that initial fill. It's a testament to a good engine. Toyotas are similar that way.
 
It’s likely regular from the dealer. Run that for a while and then run a couple of tanks of premium. You can determine which will work for you.

There has been some evidence that premium cuts down on fuel dilution. That’s an argument that will go back and forth here.

I run premium. I find that I get better response going up hills than with regular. That’s just my opinion.
Half a tank of regular just went in today. Seemed to be just as peppy, but no big hills. will compare.
 
My s-i-l has 205K on her 2015 CX-5 2.5 and I doubt it ever had a 5K OCI.....6K to 8 or 9K is more like it. It's probably never had a Mazda oil filter since leaving the factory. What it does get is a good amount of highway driving. I've settled on 6 to 7K OCI's (which is about every 4 months now) on my daughters CX-30 2.5. We'll eventually see if that's too long but I doubt it.
 
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