Trans/Primary fluid change

Discussion in 'Oil' started by FLHRC07, Nov 18, 2009.

  1. FLHRC07

    FLHRC07 Member

    Well just completed the Trans/Primary fluid change and put in the Spectro 75W140 Gear lube and for the primary heavy duty primary chain chase oil. I have been reading about the GL ratings and looking at the 75w140 is a GL1 and the 6 speed lube is a GL5.

    What the heck is the difference? I hope I did not put anything in the bike that will do damage to the trans!! What is the difference because reading what is on the spectro site the 75w140 formulated specifically for Harley big twin Trans.

    I have a 07 Road King with a 6 speed, The Bike does shift better and alot less noise from the trans since doing the change. I did look for the 6 speed stuff but was unable to find it here in Virginia Beach.

    Just want to make sure I made the right choice or do I need to get the stuff out and put something else in there.

    Thanks for any help given.
  2. glider

    glider Veteran Member

    It sounds like you used the green GL1 instead of the red GL5 in your 07 trans. The difference is with the GL5 made for 6 speeds, it has a different additive package specifically for the helical gears found in the 6 speed to minimize wear. You should be OK with the GL1 but better off when you change it to use the GL5 in yours next time.

    If any place has the GL 1, they should be able to get the GL 5 for you too or you can order it online too.

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