A reader asks: Did you hear that Harley-Davidson has a new oil filter for Milwaukee-8 engines? Apparently, it’s 1/2” longer than the previous oil filter. Is AMSOIL going to spec a longer oil filter for the Milwaukee-8 engine? Or is it even necessary?
Our answer: AMSOIL is not changing their oil filter recommendations for the Milwaukee-Eight motor. They will continue to offer the EAOM134 (black finish) and EAOM134C (chrome). These are the same filters used for the previous generation of Twin-Cam engines.
Why Did Harley Release A Longer Oil Filter For The Milwaukee-Eight Motor?
Harley-Davidson did not make this change to cure an underlying problem with their previous oil filter. It seems to be simply an effort to optimize engine protection.
Harley only offers one reason in the service bulletin announcing this new oil filter. Quote: “The increased media supports the higher flow rate of MKE-8 engines”. This doesn’t imply that the new oil filter offers more flow. They are simply saying that there is a bit more filter media surface area to accommodate the increased volume of oil flow. The Harley-Davidson bulletin also states that using the previous, shorter oil filter will not void warranty.
A longer oil filter does NOT increase the flow rate. It only increases the capacity. The filter media determines the flow rate, not the oil filter size. For example, the entire line of AMSOIL motorcycle oil filters have the same flow rate, regardless of size.
Larger oil filters tend not to translate into any sort of advantage. Consider the size of an oil filter on the average V-6 car engine. Some aren’t much bigger than a motorcycle oil filter. Yet a capacity issue is all but unheard of.
The bottom line is that the quality of the filter media is the most important factor in oil filter performance.
AMSOIL Oil Filters Are Ideal For The Milwaukee-8 Engine
AMSOIL has determined that the size and capacity of the EAOM134 and EAOM134C is more than appropriate for the Milwaukee-Eight engine.
The vital advantages offered by the AMSOIL Ea synthetic filter media are the filtration efficiency rate and exceptionally long service life. They are made to stay in service as long as AMSOIL V-Twin Synthetic 20W-50. This is 20,000 miles or one year. Therefore, capacity and service interval duration are definitely not a shortcoming with the EAOM134 and EAOM134C units. They are constructed with top-shelf components and materials. These filters are definitely built to go the distance.
AMSOIL EAOM Oil Filters also deliver world-class particle removal. They remove 98.7% of contaminants at 20-microns or larger. See how this compares to Harley Davidson’s 5-micron oil filter claims.
Will The Milwaukee-Eight Engine Run Cooler With A Slightly Longer Oil Filter?
Not likely to any measurable degree. Using AMSOIL V-Twin Synthetic 20W-50 can lower V-Twin engine temps. Our customers observe this regularly.
In conclusion, AMSOIL Synthetic Oil Filters for the Milwaukee-Eight engine provide the proper flow rate and more than enough filtering capacity. The AMSOIL EAOM134 and EAOM134C oil filters are very much an upgrade for the M-8 engine. The AMSOIL synthetic filter media is among the most sophisticated on the market. It provides exceptional protection and long service life.