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I have a quart of GM Dexron 6 ATF sitting on my shelf. Can it be used in the primary?

Do you have an extra 6 oz of it? Primary takes 38ish oz :rolleyes:
 

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I always run a quart , never any issues , and as PGR says , yes it's OK

JtB

That's why I said 38ish :rolleyes:

If you just drain and then refill, a quart is about right. But if you do an extended, several hour drain, and work the clutch, by holding it open with a zip tie, you can get several oz more out of the clutch plates.

I have a lever lift, similar to the one pictured below. I put it under the frame at the front, and lift the bike, and let it drain for at least a couple of cold beers. :cool: It's surprising how much more primary oil comes out, by lifting the front and opening the clutch plates.


 

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Very interesting about draining the primary oil out. I will do that next time around. I'm even a Rogue Chopper Scavenger oil purge guy.
 

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I don't think I'd run Dex6 in there. That's just synthetic ATF. It's quite a bit lighter than the promary needs and many ATFs have friction modifiers in them which isn't good for your clutch. Just my 2 cents.
 

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most automatic trans fluids have a viscosity of about 0W20 which is much thinner than what is recommended. as already mentioned, the friction modifiers will cause your clutch to slip and you will soon wear it out.

a friend of mine did this for some reason a couple of years ago before a week long trip we did along the blue ridge parkway, through the smoky mountains and the dragon etc, and the heat radiating from the primary after riding all the hills with the clutch slipping was ridiculous. he ended up burning the clutch out completely and all the seals in the primary ended up leaking, i assume they were also damaged from the heat. sounds a bit much, but it's what happened, i saw it.
 

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Some ancient history here so take it for what it's worth...

Back when I was serious in drag racing and Bonneville, virtually ALL of us that used a closed primary also used ATF. Type "F" (Ford) had additives that dramatically reduced clutch slippage.

BTW - this also included all of our street scoots too. A real "healthy" engine sure could overcome the grip a stock clutch offers.
 

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What's wrong with HD Formula+?? I don't get why guys want to use something sitting on there garage shelf that's not made for your bike? Spend a few bucks & purchase the proper oil. I do run Redline 20/50 & Redline Shockproof but run HD Formula+ in primary. Good luck.
 

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Every clutch manufacturer that I have ever seen recommend ATF for the primary has stated that it be "F type or non synthetic" auto trans fluid.

So I would be a little leery of putting Dex6 in there.
 

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Yep. I was using Barnett plates with some way-stiff springs in my street scoot but couldn't stop the slippage. Then a "super guru" back in my day told me what to try - ATF.He said, "GM ATF is designed to lock-up under low pressure and Ford is the other way - lock up under high pressure so use Ford". Sorry, but I don't actually know whether he meant fluid pressure or clutch pressure but I do know that back then, Type "F" was the right way to go. At least it sure did work for me.
 

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My Rivera Primo clutch i installed recommended "Mercron III". I believe Mercron is the type F fluid. Either way my clutch works very well.
 

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Automatic transmission - wet clutches.
Harley primary - wet clutches.

The ATF will work fine and will likely increase the holding power of the clutches. The problem is that the thin oil will hammer on the compensator.
 
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