BG Ultra-Guard LS diff oil

auj4 said:

Has anyone replaced their diff oil with BG Ultra-Guard LS Full Synthetic or Heavy Duty?

https://www.bgprod.com/catalog/driv...s-full-synthetic-gear-lubricant/#bg-product-1

https://www.bgprod.com/catalog/drive-line/bg-ultra-guard-ls-heavy-duty/#bg-product-1

I'm leaning towards the SAE75W-140 Heavy Duty (Full Synthetic is SAE75W-90)

I'll be replacing the gearbox oil with BG Syncro Shift II and wondering whether to do the diff at the same time.

Thanks,

auj4

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05STNG said:

What made you decide the change the grade?

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auj4 said:

I 'm understanding your question to be about the SAE75W-140 I'm leaning towards.

At low/normal temps the viscosity is unchanged. At high temps the viscosity stays closer to what the gears need instead of thinning out.

The Aussie climate is considerably hotter than most of the US (except maybe Texas/Arizona). Also the Optimum performance website seems to suggest the heavy duty for track work and reduces the temp alarms in that situation, which also implies better high temp properties. I don't intend to do any track work but I do want to keep my Stang a long time and want the best.

(Or at least thats how I understand it - Happy to be re-educated if I'm wrong).

BG Australia don't stock it and I'm waiting to hear back to find out whether they intend to bring it into Aus - So whatever I use may depend on what they bring in or whatever I can ship from the US.

The majority opinion in the US based forums seems to be the BG products are the best performing, (But after spending A$280 on 2.8L of oil, how much of that performance improvement is self justification for a bucket load of money spent ;) )

auj4

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auj4 said:

Sorry PKs,

No I never managed to source the BG 75w-140 in Oz.

(About to tick over 60k shortly. God I love driving my Pony.)

auj4

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