How often should I change the differential oil in a Mazda CX-30

Actually the Lucas does not claim anything about GL4 or Hypoid safe, I checked their photos and the full product data sheet and it is GL5 specific and that can be harsh for GL4 Hypoid gears...
 

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Where is that offered? I'm only seeing this one...
 
Where is that offered? I'm only seeing this one...
Ok, maybe that’s an old bottle, interesting. But the one on the Lucas website does specify Hypoid.
 
Ok, maybe that’s an old bottle, interesting. But the one on the Lucas website does specify Hypoid.
Yeah, looks like an older product, they may have discontinued that one as GL5 is nearly universally used for hypoid now, only Mazda calls for Hypoid AND GL4, and so far only the RP has the language I like to see in meeting that... and I don't see "hypoid" mentioned at all with the current Lucas Product.. here's the language used by RP:

"Max Gear 75W-90 is recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify the use of an API GL-5 or GL-4 fluid. It is non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe. Specially designed to extend gear and bearing life, Max Gear provides superior corrosion protection over competing conventional and synthetic gear oils. We engineered this ultra-tough, high performance automotive hypoid gear oil to provide maximum protection to heavily loaded gears while maximizing power throughout the drive train"

"Max-Gear is recommended for use in truck, motor home / RV, and automotive front or rear differentials, manual transmissions, and lower gear units of marine engines that specify the use of an API GL-5 or GL-4 fluid. Formulated with hypoid friction modifiers necessary for use in clutch or cone type differentials. Therefore no additional additives are necessary with Max Gear 75W-90."

FWIW, that was the deciding factor for me, but I appreciate the discussion!
 
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Yeah, looks like an older product, they may have discontinued that one as GL5 is nearly universally used for hypoid now, only Mazda calls for Hypoid AND GL4, and so far only the RP has the language I like to see in meeting that... and I don't see "hypoid" mentioned at all with the current Lucas Product.. here's the language used by RP:

"Max Gear 75W-90 is recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify the use of an API GL-5 or GL-4 fluid. It is non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe. Specially designed to extend gear and bearing life, Max Gear provides superior corrosion protection over competing conventional and synthetic gear oils. We engineered this ultra-tough, high performance automotive hypoid gear oil to provide maximum protection to heavily loaded gears while maximizing power throughout the drive train"

FWIW, that was the deciding factor for me, but I appreciate the discussion!
I wonder what they changed to remove gl4 compatibility. Just obsolete spec? Cheaper/easier to make now?

It does still say hypoid. On the black square. Not a big deal, I just thought it was interesting.
 

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I wonder what they changed to remove gl4 compatibility. Just obsolete spec? Cheaper/easier to make now?

It does still say hypoid. On the black square. Not a big deal, I just thought it was interesting.
Ah, yes it does on the actual label, but not in the product data sheet... but yes, this makes sense as pretty much ALL hypoid gears call for GL5 now, GL4 is mostly obsolete, so the Mazda spec (Hypoid specific AND GL4 safe) is indeed weird to begin with! So yeah, RP is the only one that says is specifically a Hypoid gear oil *and* also safe for GL4 gears which are softer metals, so that was the only one with the full language I liked to see... (Edited comment above to add an additional bit I missed in the RP description)...

I'm totally open minded to any brand if it meets all the requirements, but I'm shocked at how much of a difference this stuff made for me in my Mazda!
 
I've never had an AWD vehicle in the family until my daughter purchased her new CX-30 AWD last year.
How often should I change the differential oil and is regular 75w90 GL5 gear oil sufficient or is Mazda's OE stuff special? Does it have a differential in both the front and rear? Thanks in advance for any info on this.
What does the owners book say???? I would follow that...and use OEM fluid...IMO
 
What does the owners book say???? I would follow that...and use OEM fluid...IMO
The bottle of OEM fluid has *specific specs* to meet and I found much better fluid that actual meets those unusual specs. Do you literally only use your car manufacturer brand of engine oil too? Car makers will contract out for the cheapest possible to get you through warranty and a number of Mazda 3 AWD Turbo owners are experiencing noisy and failed differentials at well under 20k miles, saw one example of an owner that got severe whine and had to have their rear diff replaced at 5k miles. Since my car feels 500 lbs lighter, far smoother and better fuel economy, I KNOW I made the wise decision in upgrading over the cost cutting OEM junk. Is it possible Idemitsu had a bad batch recently? Sure, it's possible, but again, the difference is so monumental with the new gear oil I have no reason ever to go back, since the fluid I got meets their specs, my warranty is not only valid, I'll likely not have to worry about using it before it runs out.

Mazda also says the transmission fluid is "lifetime", yeah, if by lifetime you mean the warranty period. However, they DO have very specific "FZ" ATF fluid that you have to use, there are a handful of brands that make FZ specific fluid, I would never use FZ "suitable" multi-car fluid ever, you just have to do your research. Mazda's SkyActiv transmissions were made with the help of Aisin and Aisin has the FZ blue color specific ATF cheaper than the Mazda OEM stuff, and I trust Aisin more to make the right stuff than a 3rd party that got contracted to provide the ATF for the Mazda label.
 
The bottle of OEM fluid has *specific specs* to meet and I found much better fluid that actual meets those unusual specs. Do you literally only use your car manufacturer brand of engine oil too? Car makers will contract out for the cheapest possible to get you through warranty and a number of Mazda 3 AWD Turbo owners are experiencing noisy and failed differentials at well under 20k miles, saw one example of an owner that got severe whine and had to have their rear diff replaced at 5k miles. Since my car feels 500 lbs lighter, far smoother and better fuel economy, I KNOW I made the wise decision in upgrading over the cost cutting OEM junk. Is it possible Idemitsu had a bad batch recently? Sure, it's possible, but again, the difference is so monumental with the new gear oil I have no reason ever to go back, since the fluid I got meets their specs, my warranty is not only valid, I'll likely not have to worry about using it before it runs out.

Mazda also says the transmission fluid is "lifetime", yeah, if by lifetime you mean the warranty period. However, they DO have very specific "FZ" ATF fluid that you have to use, there are a handful of brands that make FZ specific fluid, I would never use FZ "suitable" multi-car fluid ever, you just have to do your research. Mazda's SkyActiv transmissions were made with the help of Aisin and Aisin has the FZ blue color specific ATF cheaper than the Mazda OEM stuff, and I trust Aisin more to make the right stuff than a 3rd party that got contracted to provide the ATF for the Mazda label.
On my Honda I DO use OEM fluid for the CVT and the AWD and the coolant...Mobil 1 for the engine...
 
On my Honda I DO use OEM fluid for the CVT and the AWD and the coolant...Mobil 1 for the engine...
And just like you trust Mobil 1 for your engine more than Honda brand oil, there is likely better than OEM available for your gear boxes too... But also Honda hasn't had rear diffs fail so quickly using the OEM fluid like these Mazda's have either, this is almost a must-do. The Mazda 3 added the AWD turbo model in '21 and changed the AWD software that went from virtually completely FWD until something slips to much more active electronically controlled rear diff where the rear is in play to some extent at all times. This system made its way to CX-30 and CX-5 starting in '22, and I don't think Mazda realized how much more use and strain the little gear boxes get with the big software change using the rear diff much more now and their OEM fluid doesn't appear to be cutting it.
 
And just like you trust Mobil 1 for your engine more than Honda brand oil, there is likely better than OEM available for your gear boxes too... But also Honda hasn't had rear diffs fail so quickly using the OEM fluid like these Mazda's have either, this is almost a must-do. The Mazda 3 added the AWD turbo model in '21 and changed the AWD software that went from virtually completely FWD until something slips to much more active electronically controlled rear diff where the rear is in play to some extent at all times. This system made its way to CX-30 and CX-5 starting in '22, and I don't think Mazda realized how much more use and strain the little gear boxes get with the big software change using the rear diff much more now and their OEM fluid doesn't appear to be cutting it.
Use what you want man... I will stick to OEM for what I mentioned and Mobil 1 with a FRAM filter for the engine...
 
Use what you want man... I will stick to OEM for what I mentioned and Mobil 1 with a FRAM filter for the engine...
Yes, I will thank you, and be better off for it, I wasn't trying to convince you that you had to change yours... You have a Honda and these Mazda's are a different story and why I chimed in with specific experience with my Mazda and didn't randomly jump in with what works for a completely different vehicle. This forum has very specific threads by vehicle model concern for a reason so since you jumped in you got to hear the "why" on these Mazda's, that's all...
 
Yes, I will thank you, and be better off for it, I wasn't trying to convince you that you had to change yours... You have a Honda and these Mazda's are a different story and why I chimed in with specific experience with my Mazda and didn't randomly jump in with what works for a completely different vehicle. This forum has very specific threads by vehicle model concern for a reason so since you jumped in you got to hear the "why" on these Mazda's, that's all...
Honda has a very specific oil for the CVT and the AWD differential...thats why I use OEM..
 
I did first TX case and diff oil changes 'early' on Sportage at about 20k miles, TX case fluid was worse than diff's. Both were quite dirty.
Second and trird changes showed very little contamination with 30k miles apart from initial and in between. I'm still gonna continue with 30k miles OCIs, cheap and fairly easy to do.
 
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