Diff oil

Technical Guidance for doing those Tricky Jobs

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Bloggsy
Learner Driver
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Joined: Sun Oct 28, 2018 4:11 pm
Vehicle: ND - 2 GT

Diff oil

Postby Bloggsy » Fri Mar 22, 2019 5:05 pm

Can anyone tell me which oil they have used in the diff of their ND with the LSD most lube sites say refer to Mazda specifications the only one that does list a replacement is Mobilube shc 75w90 but this dosen't deem to be available in Australia

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hks_kansei
Speed Racer
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Location: Victoria

Re: Diff oil

Postby hks_kansei » Fri Mar 22, 2019 5:16 pm

What does Mazda say to use?


Generally diffs aren't massively fussy as to what oil they use, and in a lot of cases it's the same as the gearbox.

For example, the NB just says "GL5" and doesnt specify the viscousity.



It's only really when you get to LSD type diffs that you need to be a bit more careful, with clutchpack diffs needing special LSD oils, Torsen 1 needing an oil with an EP (extreme pressure) additive, and the Torsen 2 not really caring what's in there (my diff builder said that a lot of people use ATF in their T2s, he didnt recommend it but said it hasnt had issues)

So yeah, basically, read the manual and see what it says you need.
usually it's near the back in the "fluid volumes and specifications" area or whatever they call it these days
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

Bloggsy
Learner Driver
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Joined: Sun Oct 28, 2018 4:11 pm
Vehicle: ND - 2 GT

Re: Diff oil

Postby Bloggsy » Fri Mar 22, 2019 8:09 pm

Owners manual says Mazda Long Life Hypoid Gear Oil SG1

RS2000
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Re: Diff oil

Postby RS2000 » Sat Mar 23, 2019 7:11 pm

Bloggsy wrote:Can anyone tell me which oil they have used in the diff of their ND with the LSD most lube sites say refer to Mazda specifications the only one that does list a replacement is Mobilube shc 75w90 but this dosen't deem to be available in Australia


I used to buy Mobilube SHC 75w-90 from the local Mobil depot, but never saw it in auto shops.

Bloggsy
Learner Driver
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Joined: Sun Oct 28, 2018 4:11 pm
Vehicle: ND - 2 GT

Re: Diff oil

Postby Bloggsy » Sun Mar 31, 2019 4:33 pm

Only oil company that had a listing for ND diff oil is Nulon Full Synthetic Gearbox and Transaxle 75W90 4L SYN75W90

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green_comet
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Re: Diff oil

Postby green_comet » Thu Apr 04, 2019 6:44 am

Just try to find an oil locally that meets the same builder specs as the Molilube.

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RS2000
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Location: Newcastle

Re: Diff oil

Postby RS2000 » Thu Apr 04, 2019 2:24 pm

It seems to be just 75W-90 GL5 full synthetic:
Scroll down on https://www.mobil.com/English-GB/Commercial-Vehicle-Lube/pds/GLXXMobilube-1-SHC-75W90 to find viscosity properties:
cst @ 40 deg C = 102
cst @ 100 C = 15.1
Viscosity Index = 156

Penrite Pro Gear 75W-90 is almost identical GL5 full synth.(actually, probably a bit better as same viscosity @ 100 C with a higher viscosity index)
cst @ 40 C = 95
cst @ 100 C = 15.1
Viscosity index = 168.
https://penriteoil.com.au/applications/car-4wd/gear-oils/pro-gear-75w-90-full-syn#/

Send an email to Penrite & see what they say.


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