Yes, Tuesday June 18 another enlightening evening at Roddisons Motorsport Sheffield.
Thank you Burton & Paul for organising the event. Most memorable & certainly something
all MK4 owners should be aware of is the diff, it holds only 0.7 litres of oil & can reach
180 degrees centigrade in just 20 minutes of racing!! Maybe a journey from Lancaster to
Sheffield, 97 miles, would result in similar temperatures?
Mazda it seems do not recommend a diff oil change & replenishment at all!
At the meeting an owner’s MK4 with 17k miles had the diff checked to establish how much
oil was in the diff.
Paul wagered that if the diff oil was at the correct level he would buy the beers.
Paul did not have to buy the beers. He did drain the diff & replenish with his very own
diff oil to the correct level. Result, one delighted owner.
Paul’s recommendations:-
MK4 change gear & diff oils annually
MK3 change gear oil every two years change diff oil annually.
Many other aspects of MK4 purchasing & ownership were comprehensively covered.
Definitely worth, as always, the 200 mile round trip to Roddisons.
Keith
I changed my diff oil yesterday, I too suspect the oil was not at the right level (despite having only recently asked Mazda to check it and they confirmed it was right, no surprises there!).
Its 0.6L though, whereas (I didn’t measure it accurately) but it looked at most like 0.5L that came out, it was properly drained before anyone says it.
What were the recommended gearbox and LSD oils for the ND?
After much research this is the only officially listed oil for the diff on the Mk4 ND.—Mazda part No K0209-01-SG1.
Rodders has his own blend which he will fill your diff with if you book your car in with him. I do not think he sells it as a stand alone product but please ring him to check the validity of my understanding.
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After various (helpful) emails to MX5 Parts I understand that MX5 Parts will be soon stocking the Hypoid SG1 Rear Diff oil. Approx £17.00 iirc.
I changed mine (23,000 miles 2016 2.0l ND) the other day with the SG1 I obtained from a dealer - I drained out just shot of 0.6l and added the new oil until it wept from the filler plug - as described in the work shop manual - i put in just over .7l.
There was not much “sludge” on the magnet.
I shall do this every two years I think.
Hey Nick.
Which version of the workshop manual do you have access to?
the only one I can find on-line is for the US spec 2016 model, and that states:
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Rear differential oil
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Rear differential oil capacity (approx. quantity)
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Mazda Long Life Hypoid Gear Oil SG1
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0.6 L {0.6 US qt, 0.5 Imp qt}
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And:
"DIFFERENTIAL OIL INSPECTION
3. Verify that the oil is at the brim of the filler plug hole."
Which seems to indicate you actually need >700ml…
Does it matter in the real world? No idea. ![]()
FWIW I’ll be sticking with the Mazda oil. “Secret sauce” may be fine for race use (where you have torn up your warranty on day one) but I’d rather use the stuff the manufacturer tested for millions of miles of “accelerated life” trials.
One point of interest, here is the consumables list for the Global Cup cars (note they do have both transmission and differential coolers fitted):
GMX5 Spec Fluids:
Engine Oil: 5w30 Castrol Syntec European Blend
Rear Differential Oil: 75W90 Castrol Syntrax
Transmission Oil: 75W90 Castrol Syntrax
Brake Fluid: Castrol SRF