engine and primary fluids
Club Member
Joined: Feb 2007
Posts: 16,320
Likes: 306
From: Boynton Beach, FloriDuh
holy crap, I never even noticed that and I'm a Amsoil reseller. I guess I just never looked to see cause I never thought to personally use it. I put Severe Gear in all my bikes as well as any other that comes in the shop, unless they specifically ask for another.
Thanks for pointing that out...and yes, I did miss the memo
Thanks for pointing that out...and yes, I did miss the memo
Here is why I run Red Line MT-90 (a GL4 lube) and not M1 -
1) Mobil themselves state that their GL5 can be harmful to yellow metals - http://www.mobiloil.com/USA-English/..._Gear_Oil.aspx
2) The cited study found here - https://www.hdforums.com/forum/sport...-answered.html to my knowledge was done testing the oil out of the bottle, not in real world conditions. You wont run into issues with most GL5 oils until they are exposed to heat and moisture at which point it becomes corrosive. Both of which exist in your primary.
3) According to this study - http://www.lastgreatroadtrip.com/wp-...comparison.pdf Mobil 1 is NOT MT-1 rated. MT-1 calls for a higher level of oxidation stability, which Mobil 1 does not support.
Some of the Buell guys blamed failed stators on the Mobil GL5. You can run it and you might no have any problems but there's no way its going in my bike
1) Mobil themselves state that their GL5 can be harmful to yellow metals - http://www.mobiloil.com/USA-English/..._Gear_Oil.aspx
2) The cited study found here - https://www.hdforums.com/forum/sport...-answered.html to my knowledge was done testing the oil out of the bottle, not in real world conditions. You wont run into issues with most GL5 oils until they are exposed to heat and moisture at which point it becomes corrosive. Both of which exist in your primary.
3) According to this study - http://www.lastgreatroadtrip.com/wp-...comparison.pdf Mobil 1 is NOT MT-1 rated. MT-1 calls for a higher level of oxidation stability, which Mobil 1 does not support.
Some of the Buell guys blamed failed stators on the Mobil GL5. You can run it and you might no have any problems but there's no way its going in my bike
you can see in the Amsoil data during the heat oxidation test that Mobil 1 actually outperformed Redline 75W-90 in the foam test and the viscosity percentage change. I don't know for sure if that 75W-90 is equatable to the MT-90 or not.
However, i've always steered clear of Mobil 1, because of my shop experience with those that have brought things in that have been running Mobil 1 oils. It could be standard wear on the part and more frequent use of Mobil 1 throughout the population as coincidence but, I stay away from it.
However, i've always steered clear of Mobil 1, because of my shop experience with those that have brought things in that have been running Mobil 1 oils. It could be standard wear on the part and more frequent use of Mobil 1 throughout the population as coincidence but, I stay away from it.
Last edited by Kontankerous; Sep 17, 2013 at 02:59 PM.
For me I know that the MT-90 can handle way more than our primaries could ever throw at it and there is no chance of any issues with the yellow metals
Club Member
Joined: Feb 2007
Posts: 16,320
Likes: 306
From: Boynton Beach, FloriDuh
Here is why I run Red Line MT-90 (a GL4 lube) and not M1 -
1) Mobil themselves state that their GL5 can be harmful to yellow metals - http://www.mobiloil.com/USA-English/..._Gear_Oil.aspx
2) The cited study found here - https://www.hdforums.com/forum/sport...-answered.html to my knowledge was done testing the oil out of the bottle, not in real world conditions. You wont run into issues with most GL5 oils until they are exposed to heat and moisture at which point it becomes corrosive. Both of which exist in your primary.
3) According to this study - http://www.lastgreatroadtrip.com/wp-...comparison.pdf Mobil 1 is NOT MT-1 rated. MT-1 calls for a higher level of oxidation stability, which Mobil 1 does not support.
Some of the Buell guys blamed failed stators on the Mobil GL5. You can run it and you might no have any problems but there's no way its going in my bike
1) Mobil themselves state that their GL5 can be harmful to yellow metals - http://www.mobiloil.com/USA-English/..._Gear_Oil.aspx
2) The cited study found here - https://www.hdforums.com/forum/sport...-answered.html to my knowledge was done testing the oil out of the bottle, not in real world conditions. You wont run into issues with most GL5 oils until they are exposed to heat and moisture at which point it becomes corrosive. Both of which exist in your primary.
3) According to this study - http://www.lastgreatroadtrip.com/wp-...comparison.pdf Mobil 1 is NOT MT-1 rated. MT-1 calls for a higher level of oxidation stability, which Mobil 1 does not support.
Some of the Buell guys blamed failed stators on the Mobil GL5. You can run it and you might no have any problems but there's no way its going in my bike
Time has also proven that the M1 is not responsible for stator failures, crappy HD stators are, as the failure rate is no higher with the M1 than it is with Harley's Formula+.
Stellar HDF Member
Joined: Aug 2009
Posts: 3,212
Likes: 212
I wouldn't worry too much about the yellow metals issue. The primary concern when it comes to that is phosphor-bronze gears. The (in)active sulfur reaction weakens the gear faces causing accelerated wear, and in extreme cases galling/pitting.
None of that even goes on in our transmissions. It's something that was an issue 5 years ago but has largely been surpassed with modern oils and wasn't an issue with us to begin with.
Mobil1 can't recommend it because they didn't design it for that purpose explicitly, simple as that. Just like they tell me I can't run the 15W-50 auto oil in my engine sump; you know, because a Harley engine is soooo much different than any other pushrod OHV engine (cough, SBC, cough).
None of that even goes on in our transmissions. It's something that was an issue 5 years ago but has largely been surpassed with modern oils and wasn't an issue with us to begin with.
Mobil1 can't recommend it because they didn't design it for that purpose explicitly, simple as that. Just like they tell me I can't run the 15W-50 auto oil in my engine sump; you know, because a Harley engine is soooo much different than any other pushrod OHV engine (cough, SBC, cough).
Last edited by Scuba10jdl; Sep 17, 2013 at 03:46 PM.
Here is one of the threads from the Buell guys discussing how M1 can fail the stators - http://www.badweatherbikers.com/buel...38/549747.html
"I had a stator failure on my S3 using Mobil-1 gear oil. When I replaced the stator, the one obvious thing that was wrong was the potting material around the solder joints (where the external leads connected to the stator windings) was severely deteriorated. It maybe that something in the gear oil attacks this stuff (epoxy or something similar) letting the leads short out and causing the failure."
"I had a stator failure on my S3 using Mobil-1 gear oil. When I replaced the stator, the one obvious thing that was wrong was the potting material around the solder joints (where the external leads connected to the stator windings) was severely deteriorated. It maybe that something in the gear oil attacks this stuff (epoxy or something similar) letting the leads short out and causing the failure."
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
Club Member
Joined: Feb 2007
Posts: 16,320
Likes: 306
From: Boynton Beach, FloriDuh
Here is one of the threads from the Buell guys discussing how M1 can fail the stators - http://www.badweatherbikers.com/buel...38/549747.html
"I had a stator failure on my S3 using Mobil-1 gear oil. When I replaced the stator, the one obvious thing that was wrong was the potting material around the solder joints (where the external leads connected to the stator windings) was severely deteriorated. It maybe that something in the gear oil attacks this stuff (epoxy or something similar) letting the leads short out and causing the failure."
"I had a stator failure on my S3 using Mobil-1 gear oil. When I replaced the stator, the one obvious thing that was wrong was the potting material around the solder joints (where the external leads connected to the stator windings) was severely deteriorated. It maybe that something in the gear oil attacks this stuff (epoxy or something similar) letting the leads short out and causing the failure."
The following samples (from your source) could have easily come from a parrot.
You should not use their GL-5 products as it could attack red metals like the stator. (Red metals in the stator? Yea, I believe this guy)
Yes, GL-5 gear oils are known to eat the stators. (All GL-5's? How about, it's been scientifically proven SOME GL-5 oils can be harmful)
You've been provided with links to scientific test data on various GL-5 oils, some of which like M1, have past with flying colors, and others that have not. Interestingly, you seem choose to ignore the scientific test data in lieu of unfounded wives tales found on an internet forum.
Then there's your own experience with a stator in which the problem appeared to be the deterioration of the epoxy potting compound. That's certainly not a "yellow metal" related issue, and the first claim I've seen that GL-5 attacks epoxy.
The good news is that it's a free country and you have lots of products to choose from.
Sorry, but your "source" is nothing more than another internet forum where the posters are making unsubstantiated claims that have no basis in scientific fact or testing.
The following samples (from your source) could have easily come from a parrot.
You should not use their GL-5 products as it could attack red metals like the stator. (Red metals in the stator? Yea, I believe this guy)
Yes, GL-5 gear oils are known to eat the stators. (All GL-5's? How about, it's been scientifically proven SOME GL-5 oils can be harmful)
You've been provided with links to scientific test data on various GL-5 oils, some of which like M1, have past with flying colors, and others that have not. Interestingly, you seem choose to ignore the scientific test data in lieu of unfounded wives tales found on an internet forum.
Then there's your own experience with a stator in which the problem appeared to be the deterioration of the epoxy potting compound. That's certainly not a "yellow metal" related issue, and the first claim I've seen that GL-5 attacks epoxy.
The good news is that it's a free country and you have lots of products to choose from.
The following samples (from your source) could have easily come from a parrot.
You should not use their GL-5 products as it could attack red metals like the stator. (Red metals in the stator? Yea, I believe this guy)
Yes, GL-5 gear oils are known to eat the stators. (All GL-5's? How about, it's been scientifically proven SOME GL-5 oils can be harmful)
You've been provided with links to scientific test data on various GL-5 oils, some of which like M1, have past with flying colors, and others that have not. Interestingly, you seem choose to ignore the scientific test data in lieu of unfounded wives tales found on an internet forum.
Then there's your own experience with a stator in which the problem appeared to be the deterioration of the epoxy potting compound. That's certainly not a "yellow metal" related issue, and the first claim I've seen that GL-5 attacks epoxy.
The good news is that it's a free country and you have lots of products to choose from.
As you said:
Stator #3 just took a dump after only 13,000 miles.
#1 @ 24,000 miles
#2 @ 50,000 miles
#3 @ 63,000 miles
That's enough proof for me