Hypoid Gear Oil?

[oldhway]

Ok, so it's a thread about oil; I apologize in advance to those who have seen too many oil threads.

I have a question about folks experience with the oil in the final drive, not the transmission. BMW designates Hypoid gear oil for both the final drive and the transmission. I have been running Mobil 1 gear oil in the tranny but have been using motorcycle specific Hypoid drive oil in the final. I have read some folks have used the Mobil 1 gear in the final as well. I have checked the bottle and although the Mobil 1 is designated GL5, I don't see the Hypoid designation. What the heck is Hypoid and is the designation significant. In the owners manual on CD that I have, it designates Hypoid for the tranny as well, but most of the oil posts I have read seem to ignore this. I ride a 2004 R1150RT specifically and am probably going to go to the Mobil 1 in the final drive as well as the tranny, but have read so many horror stories about drivetrain failures that I wanted to do just a little more research.

FYI, My question is to avoid problems. Although I know running the manufacture specified oil is neccessary for warranty, a broken motorcycle (warranty or no) does me no good so I am not really looking to address warranty concerns here.

Any thoughts or experiences are gratefully appreciated......

 

[ssls6]

Ok, so it's a thread about oil; I apologize in advance to those who have seen too many oil threads.

I have a question about folks experience with the oil in the final drive, not the transmission. BMW designates Hypoid gear oil for both the final drive and the transmission. I have been running Mobil 1 gear oil in the tranny but have been using motorcycle specific Hypoid drive oil in the final. I have read some folks have used the Mobil 1 gear in the final as well. I have checked the bottle and although the Mobil 1 is designated GL5, I don't see the Hypoid designation. What the heck is Hypoid and is the designation significant. In the owners manual on CD that I have, it designates Hypoid for the tranny as well, but most of the oil posts I have read seem to ignore this. I ride a 2004 R1150RT specifically and am probably going to go to the Mobil 1 in the final drive as well as the tranny, but have read so many horror stories about drivetrain failures that I wanted to do just a little more research.

FYI, My question is to avoid problems. Although I know running the manufacture specified oil is neccessary for warranty, a broken motorcycle (warranty or no) does me no good so I am not really looking to address warranty concerns here.

Any thoughts or experiences are gratefully appreciated......

Hypoid is a geometric term used to describe a gear's tooth shape and contact path. With respect to gear lubes, hypoids require GL5 level protection. So, pick your favorite GL5 and put it in.

 

[nrpetersen]

Technically a hypoid axle does not have the pinion axis intersecting the ring gear axis. It is commonly used on rear wheel drive automotive applications where the driveshaft was deliberately depressed to give a flatter floor in the passenger compartment.

This means that the right angle drive is really a combination of a bevel gear set (which is as efficient as any gear set) and a worm gear set (which is inefficient as hell). There is a sliding contact in a hypoid gearbox, and that's why they are so inefficient. It is one of the reasons the old rear wheel drive cars had higher fuel consumption compared to front wheel drive vehicles. I understand about 10% of the input power is lost in a hypoid axle. An antiwear additive in the lubricant is necessary to handle the sliding motion. I understand the sulfur etc stink of rear axle oils is the hypoid antiwear additves.

Our RD units are only bevel or spiral bevel gears, which means they should be efficient, but the antiwear additves are necessary to handle the slight amount of sliding that is present in any involute gear set.

Or was that maybe more than you wanted to know..........? (Class dismissed!)