Oil Suggestions For Harleys (updated)
Here is a listing of the many oils that you can choose from...
An online source for Spectro oils...
Spectro Shop
You can also order direct from Spectro...
Spectro Oils of America
You can find cross references for HD oil to Spectro here...
HD/Spectro Cross Reference - Harley Davidson Community
A straight weight oil is not recommended for the newer TC engines.
My thoughts on HD brand oil is their Syn 3 is not good choice when there are so much better oils available. It is a group 3 oil when most of the others are at least a group 4 or better meaning it is not a full synthetic but a blend of oils.
Their HD 360 non synthetic is a good oil however.
The HD oil filters are specked for the Harley engines and using another brand is a chance to take after considering the filter media size in microns and bypass spring pressure. If it opens too low, your engine will run on unfiltered oil.
Also never confuse a Twin cam oil filter and an EVO oil filter or you will have big problems. Basically the EVO oil filter is 30 microns in filter media and the Twin cam is now 5 micron. The oil jets that cool the bottom of the pistons in a twin cam engine need the 5 micron rating otherwise they will not be able to function once they get clogged and the pistons will heat up more than they should.
Mobil 1 V Twin 20/50 is designed for the V-Twin engine, some people use the regular Mobil 1 car oil but it lacks the necessary additive packages (one being moly that is an anti wear agent) to stand up to the heat of the Harley air cooled engine which runs much hotter than the car counterpart because of the water cooling.
For the transmission, Mobil 1 Synthetic Gear Lube
LS 75W-140 or 75W90 is a good choice also in the big twins.
Redline Shockproof Heavy is also a good choice in the transmissions of big twins.
For the sportster primary case/trans which share oils , this is a good choice.
Spectro Oils of America - Transmission Gear Oils
Heavy Duty Primary Chain case Oil
This sheer stable petroleum is designed to withstand the punishment of high loads, and contains special polymers to provide exceptional clutch engagement and temperature stability. Meets full OEM requirements, and should be used according to manufacturer’s instructions. Formulated specifically for Harley® Sportster and Big Twin applications. Low drag, low friction loss SAE 85w viscosity eliminates clutch “drag” and slipping. 85w R.GAPCL 12/1 qt bottles/case 85w X.GAPCL 16 gal drum.
GL 1 which is for 5 speed and 4 speed transmissions.
Redline shockproof heavy for the trans (it's a gear oil) or Mobil 1 gear oil 75/90 or 75/140 will do nicely also.
I just tried a "new for me" product by Spectro oils on the advice of a friend. I have used their oil in the past and liked the results. I installed this oil yesterday 10/13/07 and I am impressed with it over the Mobil 1 75/90 and 75/140 synthetics that I have tried and used since the bike was new.
It's Spectro Heavy Duty Platinum 75/140 for helical and straight cut gears, made especially for 6 speed transmissions. It has a rating of GL5 and I think I have found a new oil for my transmission. The shifting is better , smoother and also quieter. Cost is about $16 a quart but well worth it IMO. I thought the Mobil 1 and redline shock proof heavy worked well until I tried this oil.
Heavy Duty Platinum 6-speed Transmission Oil
Designed by Spectro in response to complaints from Harley owners about the great but noisy new 6-speed transmission, this full synthetic provides ultimate lubrication protection. Formulated to significantly reduce gear noise and provide easier, smoother shifting, this SAE 75w140 which is red in color with a formulation to ease shifting even when cold. High loads and extreme heat do not affect the oil, so it performs well when pushed hard and long. A.P.I. GL-5 rated.
The GL1 is for the 5 speed transmissions and is green in color to distinguish it from the GL 5.
Royal purple oils , Lucas oils and Golden Spectro are an excellent choice also.
In the primary pretty much any 10/30 - 10/40 without friction modifiers in it will do the job.The HD Formula+ from the dealer will work well here too, also Spectro chain case lube will work well too.
Or if you prefer a Spectro product...
Formulated specifically for Harley® Sportster and Big Twin applications. Low drag, low friction loss SAE 85w viscosity eliminates clutch “drag” and slipping.
You can use the formula + in the primary but I would not use it in the trans because it falls short there in the severe service category.
Changing from one brand to another brand will cause no problems at all or from dino oil to synthetic oil will mix also with no problems when changing over.
Here's some input on the rating of the various lubes. It's not a recent posting but may give you a better understanding.
GL gear_lube_designations
Here is a listing of the many oils that you can choose from...
An online source for Spectro oils...
Spectro Shop
You can also order direct from Spectro...
Spectro Oils of America
You can find cross references for HD oil to Spectro here...
HD/Spectro Cross Reference - Harley Davidson Community
A straight weight oil is not recommended for the newer TC engines.
My thoughts on HD brand oil is their Syn 3 is not good choice when there are so much better oils available. It is a group 3 oil when most of the others are at least a group 4 or better meaning it is not a full synthetic but a blend of oils.
Their HD 360 non synthetic is a good oil however.
The HD oil filters are specked for the Harley engines and using another brand is a chance to take after considering the filter media size in microns and bypass spring pressure. If it opens too low, your engine will run on unfiltered oil.
Also never confuse a Twin cam oil filter and an EVO oil filter or you will have big problems. Basically the EVO oil filter is 30 microns in filter media and the Twin cam is now 5 micron. The oil jets that cool the bottom of the pistons in a twin cam engine need the 5 micron rating otherwise they will not be able to function once they get clogged and the pistons will heat up more than they should.
Mobil 1 V Twin 20/50 is designed for the V-Twin engine, some people use the regular Mobil 1 car oil but it lacks the necessary additive packages (one being moly that is an anti wear agent) to stand up to the heat of the Harley air cooled engine which runs much hotter than the car counterpart because of the water cooling.
For the transmission, Mobil 1 Synthetic Gear Lube
LS 75W-140 or 75W90 is a good choice also in the big twins.
Redline Shockproof Heavy is also a good choice in the transmissions of big twins.
For the sportster primary case/trans which share oils , this is a good choice.
Spectro Oils of America - Transmission Gear Oils
Heavy Duty Primary Chain case Oil
This sheer stable petroleum is designed to withstand the punishment of high loads, and contains special polymers to provide exceptional clutch engagement and temperature stability. Meets full OEM requirements, and should be used according to manufacturer’s instructions. Formulated specifically for Harley® Sportster and Big Twin applications. Low drag, low friction loss SAE 85w viscosity eliminates clutch “drag” and slipping. 85w R.GAPCL 12/1 qt bottles/case 85w X.GAPCL 16 gal drum.
GL 1 which is for 5 speed and 4 speed transmissions.
Redline shockproof heavy for the trans (it's a gear oil) or Mobil 1 gear oil 75/90 or 75/140 will do nicely also.
I just tried a "new for me" product by Spectro oils on the advice of a friend. I have used their oil in the past and liked the results. I installed this oil yesterday 10/13/07 and I am impressed with it over the Mobil 1 75/90 and 75/140 synthetics that I have tried and used since the bike was new.
It's Spectro Heavy Duty Platinum 75/140 for helical and straight cut gears, made especially for 6 speed transmissions. It has a rating of GL5 and I think I have found a new oil for my transmission. The shifting is better , smoother and also quieter. Cost is about $16 a quart but well worth it IMO. I thought the Mobil 1 and redline shock proof heavy worked well until I tried this oil.
Heavy Duty Platinum 6-speed Transmission Oil
Designed by Spectro in response to complaints from Harley owners about the great but noisy new 6-speed transmission, this full synthetic provides ultimate lubrication protection. Formulated to significantly reduce gear noise and provide easier, smoother shifting, this SAE 75w140 which is red in color with a formulation to ease shifting even when cold. High loads and extreme heat do not affect the oil, so it performs well when pushed hard and long. A.P.I. GL-5 rated.
The GL1 is for the 5 speed transmissions and is green in color to distinguish it from the GL 5.
Royal purple oils , Lucas oils and Golden Spectro are an excellent choice also.
In the primary pretty much any 10/30 - 10/40 without friction modifiers in it will do the job.The HD Formula+ from the dealer will work well here too, also Spectro chain case lube will work well too.
Or if you prefer a Spectro product...
Formulated specifically for Harley® Sportster and Big Twin applications. Low drag, low friction loss SAE 85w viscosity eliminates clutch “drag” and slipping.
You can use the formula + in the primary but I would not use it in the trans because it falls short there in the severe service category.
Changing from one brand to another brand will cause no problems at all or from dino oil to synthetic oil will mix also with no problems when changing over.
Here's some input on the rating of the various lubes. It's not a recent posting but may give you a better understanding.
GL gear_lube_designations
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