Best Gear Oil?

I've been using Mobil 75W/90 in both the RK and Rocket i just spent two hours and got about fifty different answers on SHC and LS usage. A lot of Harley owners have been using the LS. I'd be interested in what the experts have to say also...

Hmmm Harley Shaft drive?
I've been using Mobil 75W/90 in both the RK and Rocket i just spent two hours and got about fifty different answers on SHC and LS usage. A lot of Harley owners have been using the LS. I'd be interested in what the experts have to say also...

The only transmission oil Harleys would be using is in the gearbox a different(pardon the pun) kettle of fish to the differential ,they did make a shaft drive in 1942 for the US Army, 1000 made designated XA experimental Army, a dismal failure from all accounts .
 

I use Mobil 1 20W/50 for the engine oil and primary. The 75W/90 in the tranny of the Roadking. With the newer 6 speeds a lot are switching over to the 70W/140. Here in New England that's a little to thick for our temps.Harley wants you to use their tranny oil 99892-84 which is made by the lowest bidder it's either Delray or Sunoco then they mark it way up and tell you it's the best oil since sliced bread,in any case (pardon the pun) Mobil 70W/90 is what most are using as an alternative .Which is also what Triumph recommends for the Final Drive in the Rocket.
 
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I love a good Pun, Quoting Verbatim from my Triumph R3T Owners Handbook ,Under Fluids and Lubricants ,Final drive Mobilube SHC 75w-90 fully synthetic Hypoid oil (or equivalent)
Engine Oil Semi or fully synthetic 10W40 or 15W40 Motorcycle Engine oil which meets Specification API- SH or higher and JASO MA such as Mobil 1Racing 4T.
I use Maxima Triple Ester Formula Extra 4 100% Ester Based Synthetic SAE 10w 40 Motor cycle specific exceeds A.P.I SG /CC , dear as poison, but hang the expense throw the cat another goldfish LOL!
 
I understand that.... but if someone can't find the Mobil SHC 75W/90 what if any difference is there in using the Mobile LS 75W/-90. That's the 64 thousand question..
 
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I understand that.... but if someone can't find the Mobil SHC 75W/90 what if any difference is there in using the Mobile LS 75W/-90. That's the 64 thousand question..
They both read the same applications so maybe some minor production variations , I don't think you could go too wrong using either , my humble opinion only!
 
That's the one I use as it was the sticker on the diff housing when I got the Bike, and the service specifications specify this lubricant.

Where do you buy Castrol Syntrax Long Life? The Triumph dealer? I can't find it in the USA.
 
Where do you buy Castrol Syntrax Long Life? The Triumph dealer? I can't find it in the USA.

just about any bike shop ,I buy mine from Supercheap Auto a motor accessory chain in Australia not cheap around $30 a litre but you get a couple of oil changes out of that
 
just about any bike shop ,I buy mine from Supercheap Auto a motor accessory chain in Australia not cheap around $30 a litre but you get a couple of oil changes out of that


Ken, I didn't notice that you were in Australia, which I think explains the availabity of it in your stores.
 
Make sure it's GL-5 rated. I used the Valvoline multi-weight.
 
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