What Type Of Gear Oil Should I Use

A reader asks: "I'thou looking to switch my Harley-Davidson Street Glide Special over to AMSOIL. Obviously the engine volition accept your constructed 20W-l, merely I'm curious nearly what to utilise in the primary and transmission. There are a lot of different combinations put out at that place on the net. Some apply gear lube in the transmission and chaincase. Some fifty-fifty use ATF in chaincase and merits they take keen results. What is the best combination for my bike?"

Answer: For any Harley Twin-Cam engine, nosotros highly recommend using AMSOIL Synthetic 20W-50 in "all three holes" (as they put information technology) for ii essential reasons.

Update: AMSOIL now offers dedicated fluid for Harley Davidson primary concatenation-cases and transmissions. These are called AMSOIL Five-Twin Chief Oil and AMSOIL 5-Twin Transmission Oil. Should ane use these defended fluids? Or is AMSOIL V-Twin 20W-50 adequate for primary and transmission use? There truly is no wrong answer. AMSOIL V-Twin 20W-50 is designed for engine, chief and transmission use. It is certainly a highly competent and user-friendly choice for all iii components. For those that prefer a specialized fluid, the Five-Twin Primary and V-Twin Transmission Fluids will certainly provide outstanding performance and protection.

Related: Run across All Of Our Manufactures On Harley-Davidson Motorcycles And Synthetic Oil

AMSOIL V-Twin 20W-50 Works (and works very well indeed)

AMSOIL 20W-50 Synthetic Motorcycle Oil is specifically designed to withstand the rigors of engine, transmission and principal chaincase use. Expect smooth, placidity shifting with maximum component life. Information technology is contains additives to prevent wear and the 100% synthetic base oil will not shear down (thin out). Therefore, information technology volition not leave manual or primary components vulnerable to accelerated wear.

AMSOIL has secondary recommendations of AMSOIL Astringent Gear 75W-110 for the transmission and Severe Gear 75W-140 for the primary, just the visitor themselves will tell you that at that place is absolutely no upside to using gear oil in these components rather than the 20W-fifty. Some may think that they are using a thicker oil by using a gear lube. Only remember that engine oils and gear lubes use different viscosity scales to prevent defoliation.

What About Gear Oil?

Let's look at the actual viscosity numbers of AMSOIL 20W-50 Motorcycle Oil and AMSOIL Astringent Gear 75W-90, 75W-110 and 75W-140. The industry standard for measuring viscosity is in "centistokes" at 100°C.

"MCV"AMSOIL 20W-50: xviii.five
"SVG" Severe Gear 75W-xc: sixteen.eight
"SVT" Severe Gear 75W-110: 21.three
"SVO" Astringent Gear 75W-140: 27.5

AMSOIL V-Twin Synthetic 20W-50 Motorcycle Oil Every bit you can run into, the 20W-50 motorcycle oil is relatively close to the 75W-110 in terms of bodily viscosity. So those opting for a gear lube thinking that they are using thicker oil, really are not. Those using an 80W or 75W-90 in their transmissions are actually using a much thinner oil. The 20W-50 motorcycle oil's viscosity is right in the "sweet spot" for optimum operation in all three holes and the volumes of positive reviews we receive back this up.

Gear lubes practice contain heavy doses of "extreme force per unit area" additives which many believe prevent transmission article of clothing and provide quieter performance. Over again, AMSOIL 20W-fifty Motorcycle Oil is packed with additives specifically designed to prevent wear in clutches, gears, bondage and sprockets. In that location is absolutely no downside to going the 20W-l route.

Some tout the apply of automatic transmission fluid (ATF) in Harley master chaincases. We do not recommend this pick. Again, permit'south look at bodily viscosity numbers to dorsum this upwards. The viscosity of a typical ATF at 100°C is 7.5 centistokes. We submit that ATF viscosity is far too thin for this application and think that the hazard of long term wear is far likewise smashing. AMSOIL 20W-50 has a viscosity of 18.5 centistokes.

Convenience: 1 Effective Production For Everything

The second main reason that nosotros recommend using 20W-50 motorcycle oil in the engine, manual and primary chaincase is that you lot can buy 1 product for everything. Therefore, you can keep ane product on hand and bring one oil along on trips for top-ups. In conclusion, only does AMSOIL Constructed 20W-l work uncommonly well in all three holes, it keeps things simple.