Mazda Long Life Hypoid Gear Oil SG1

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In 2016, Mazda changed the recommendation for the transfer case and rear differential on the CX-5 from an 80w90 GL-5 to Mazda Long Life Hypoid Gear Oil SG1. Anyone have any technical data on this Mazda OE fluid?
 
My transfer case and rear diff change is coming up in a little less than 5k miles. Gonna bump this in case anyone has learned anything on this fluid, or discovered a suitable aftermarket alternative.
 
I own a 2019 Miata. One thing I did was check fluid levels. My diff takes Hypoid gear SG1 and was just a bit low so I bought 2 quarts. My diff. Only takes .6 quart and used just a little bit of one bottle. The scheduled maintenance calls for a change if the rear axle gets submerged and has no set time or mileage for change. I assume you want to change it to feel warm and fuzzy?
 
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Originally Posted by Bill_W
I assume you want to change it to feel warm and fuzzy?


Pretty much. Manual calls for a 75k spark plug change, figured I'd take care of drive train fluids at that time also.
 
bump,
my 16 cx5 awd manual recommend changing the diff fluid at 28k miles under severe service,
my severe usage is very short daily trips,like 3-4miles total a day in two trips in city low speeds.
the dealership said they never change the diff oil only if it sank in water.
should i change it anyway?
tnx.
 
Originally Posted by RamFan
In 2016, Mazda changed the recommendation for the transfer case and rear differential on the CX-5 from an 80w90 GL-5 to Mazda Long Life Hypoid Gear Oil SG1. Anyone have any technical data on this Mazda OE fluid?



Before asking this type of question - Have the fluid analyzed in a VOA so we can determine viscosity and elemental values.
 
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Originally Posted by avi1777
bump,
my 16 cx5 awd manual recommend changing the diff fluid at 28k miles under severe service,
my severe usage is very short daily trips,like 3-4miles total a day in two trips in city low speeds.
the dealership said they never change the diff oil only if it sank in water.
should i change it anyway?
tnx.



I would refresh it under the Severe Service interval.
 
bought 1quart from ebay which cost me 50$,beacuse sg1 is no where to be found in israel,now I see I will need a quart plus 150cc more or less for the diff and transfer 🤦â€â™‚ï¸
 
For those who might stumble on this and are curious, I switched to Royal Purple Max Gear 75w-90 in my Mazda 3 AWD Turbo for the transfer case and rear diff, each takes only 0.37 qt. I immediately noticed far less drivetrain drag, it's good stuff! Starting with the '21 Mazda 3 AWD Turbo and in their SUV's in following years, they made their AWD system far more active with the rear involved at least a little at all times. Mazda SG-1 is 75w-85 GL-4 Hypoid oil and at the time the Royal Purple was the only one that mentioned is GL4+, safe for hypoid gears and has hypoid gear additives already. I now have found an oil that meets actual SG-1 spec and that is Ravenol DTF-1 Transfer Case fluid. if anyone is curious on alternatives, I know there are a number of people with the Mazda 3 AWD Turbo with rear diff issues, could be with the AWD system far more active in the rear now that the little gear boxes need better fluid!
 
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I also used RP Max Gear 75w90 in the rear differential of my daughter's CX-30 and it seems to be working fine.
When I went to change the transfer case fluid in the front end it had a different fill plug than shown on a Youtube
video for the CX-5 (there was no YT on the CX-30 yet). The CX-5 had a big bolt type plug (24mm IIRC)...the CX-30 seems to have a smaller plug which uses a hex key to open. The problem I found is that the plug seems to be blocked from removal by the transaxle mount. I'm now wondering if I put it on ramps (rather than on jackstands with the wheels hanging) will it enable the plug to clear the mount?
 
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I also used RP Max Gear 75w90 in the rear differential of my daughter's CX-30 and it seems to be working fine.
When I went to change the transfer case fluid in the front end it had a different fill plug than shown on a Youtube
video for the CX-5 (there was no YT on the CX-30 yet). The CX-5 had a big bolt type plug (24mm IIRC)...the CX-30 seems to have a smaller plug which uses a hex key to open. The problem I found is that the plug seems to be blocked from removal by te transaxle mount.
Yep, with my Mazda 3 it was a 8 Allen key for the fill and 24 mm for the drain on the transfer case. On the differential it was 23mm for the fill and 24mm for the drain... I'm assuming for the CX-30 it should be the same.
 
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Yep, with my Mazda 3 it was a 8 Allen key for the fill and 24 mm for the drain on the transfer case. On the differential it was 23mm for the fill and 24mm for the drain... I'm assuming for the CX-30 it should be the same.
Did you have any issue with the corner of the Allen key bolt being blocked by what appears to be a mount?
 
Did you have any issue with the corner of the Allen key bolt being blocked by what appears to be a mount?
I had someone else do it at the time as I was really sick, but from what I've heard they or others didn't have any issues that I'm aware of.
 
I would probably use ST 75w90 synthetic from Walmart
Did you miss the part of the discussion where there are certain specs you have to hit? It needs to be GL4 and specifically for hypoid gears, which is a rare combo. If you use random 75w-90 that is only GL5 you can damage the softer metals used.
 
Did you miss the part of the discussion where there are certain specs you have to hit? It needs to be GL4 and specifically for hypoid gears, which is a rare combo. If you use random 75w-90 that is only GL5 you can damage the softer metals used.

Yeah, I missed that. It wasn't in the OP or any post made by the OP, but I just saw yours now :oops:

However, the original recommendation of 80w90 GL5 can be replaced with 75w90 GL5 with no problem, and most people never change the gear oil in their diffs anyway, so they will arrive at the junkyard on the original 80w90 GL5 from the factory.

Since it's a Mazda, the car will rust out before the gear oil becomes a problem :sneaky:

Maybe Motul Gear 300 might be a good choice. It's primarily intended for Subaru manual transmissions that are combined with the front diff, so both GL4 and GL5 are needed :unsure:
 
Yeah, I missed that. It wasn't in the OP or any post made by the OP, but I just saw yours now :oops:

However, the original recommendation of 80w90 GL5 can be replaced with 75w90 GL5 with no problem, and most people never change the gear oil in their diffs anyway, so they will arrive at the junkyard on the original 80w90 GL5 from the factory.

Since it's a Mazda, the car will rust out before the gear oil becomes a problem :sneaky:

Maybe Motul Gear 300 might be a good choice. It's primarily intended for Subaru manual transmissions that are combined with the front diff, so both GL4 and GL5 are needed :unsure:
The original SG-1 is actually 75w-85, otherwise 75w-90 is indeed totally fine as a weight, but it does needs to be both GL4 AND specifically have the right additives for hypoid gears, not random manual transmission fluid. Sorry, not trying to be a smart-Alec, but that point seems to keep being missed.
 
The, its needs to be only GL4 for diff/xfercase, is bull produced fertilizer.

Dropping from a 80w90 to a 75w85 is simply for MPG and not all that critical.

The xfer case isn't going to care whether its GL4 or GL5, and I would definitely use any random GL4 MT fluid without worry or any locally available GL5 too. There are plenty of 75w85 and 75w90 GL4 and/or GL5 gear oils.

I wouldn't use a GL4 in a rear differential. Dropping from a GL5 to a GL4 in the rear differential is a bit worrying. But, part time wimpy AWD systems don't send too much power back there for much time. So, its hopefully a lightly loaded at most, non stressed differential, and I'd wager Mazda is gambling with the typical US consumer and their warranty. Who cares about the longevity of a differential!!!!!
I would just use any 75w90 GL5 gear oil, preferably without LS additive, in the rear diff. There are GL5 75w85's if you want the MPG.

I prefer the 90 grade protection. If it were mine, I'd use Motul Gear300, Redline NS, Delvac1, or any equivalent Mack GO-Jplus 75w90.
 
I'm about to do mine next week. Good to know there's another option; I was leaning towards the OEM fluid.
 
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