Frankly, you don't need to change it often at all. How often do you change the fluid in an automobile, manual or automatic? If you use syn fluid especially, I wouldn't change it til you find yourself with nothing better to do.

 

Automotive tranny fluids are the most neglected item on many vehicles until its too late.Fluids are cheap compared to rebuilds.A new anything will make some kind of debri over time.Changing alittle early when new and slowly going to factory recs would be a good option.

 

Don't get me wrong...I'm not being a tight a$$ over a couple of bucks for my tranny...I'm thinking some of the folks who only change it out once a year are not riding that often.....I'll be sticking to my usual regime of changing all my fluids every 4-5 thou...

 

I log about 30,000 miles a year here in So Cal -daily rider with a one-hour commute each way, somy bike gets run hard.Synthetic oils and frequent changes are cheap insurance!

 

I presently run Mobil1 75/90.......I change mine every 2500 when I do the oil change. Funny thing from my experience though, I ran Redline for a while then went to Mobil 1.....in mine, Mobil1 shifts much better...go figure...

 

Well, if you go by "The Book", the book for my 01 FLTRSEI2 says to change the trans every 5K. The book for my 06 FLHTCI says to change it every 20K. That's a significant difference that may be accounted for by improvement in lubes? I guess we all do what we gotta do. Right now one bike has Redline in it and the other is running Amsoil.

 

My book says 5,000 for everything as "normal" maintenence. Since I do it myself it's an extra $16 to change the trans & primary.......I spend that much on beer in a weekend easy. Changing oil is just too important to let slide.

 

If Redline reccommends 10,000 and my manual says 5000 I'm changing mine at 7500 because I run redline in my tranny. If the oil at 7500 looks really dirty I'll go back to 5000. Youshould change your oils at operating temp. Also cut open your engine filter and inspect.

 

The 06 and 07 big twins state every 20,000 in the HD service specs. HD dont want their bikes to self destruct for the sake of a little oil, and they should know what they are doing as they have been around a lot longer than me.

I ran the HD oil for 1000 miles and changed to the RedLine Shockproof Heavy which will stay in till 10,000 (9,000 miles), and then I will change every 10,000 miles. I think that cutting the service interval in half and using quality oil is plenty safe enough. And really I'm only doing it at 10,000 to tie in with the primary oil changes.

WB

 

I agree. My manual ('07 SG) says 5k for engine, 10k for primary, and 20k for tranny. My ritual has always been 5k for all three holes, but for this new bike I'm going to change to 5k, 5k, and 10k, respectively. The engine oil is a no-brainer, and I'm sticking with 5k for the primary since it is always grungy-looking at 5k with clutch material floating around in it, but the tranny oil never looks contaminated at that mileage. After all, how many of us change the fluid in our car's manual trannies or differentials every 5k, or even every 10k? My car's manual tranny doesn't even have a change interval for the life of the car, and I think most are like that nowadays.

FWIW, my choice for the tranny is Royal Purple 85w140, which quietened my 6-speed considerably. Anyone having issues with tranny noise, try using the thicker viscosity gear oil of your choice.