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200XMichigan
03-30-2010, 12:49 PM
I have always bought fork oil but I have also heard that ATF (Dextron/Mercron) will work fine. Is there any reason not to use ATF? Other than that you cannot fine tune the weight of the oil. Since you can buy 5,10,15 WT fork oil but ATF is around a 10.
WIkid500
03-30-2010, 12:54 PM
I have ATF in my 200x right now. It said to use ATF in the Honda manual so I did. I think fork oil is out there is for the adjustability in different oil weights like you said. Maybe the fork oil holds up better, longer? I'm not sure on that one. I have never experimented with different shock oils so I wouldn't know how much of a difference they make.
NINJA
03-30-2010, 07:40 PM
ATF weight is comparable to 7.5 WT. The reason the manuals call for it is because ATF is always consistent in weight no matter what brand, for it to meet automotive standards. This is not the case with suspension oils. For example, Belray 5 WT is not the same as Maxima 5 WT. The difference can be as much as 3 points. This is the reason why some of the manuals specify what brand of fork or shock oil to use on the newer bikes.
And yes, there is a difference between fork and shock oil.
m brater
03-30-2010, 07:56 PM
I was told by a head mechanic at a honda dealer that ATF is old school and fork oil has special conditioners to keep the seals softer and last longer and seal better.
200XMichigan
03-30-2010, 08:45 PM
I feel dumb for asking, should have had more coffee this morning. That's where I "heard" it was my 200X manual.
3wheelmecca
03-30-2010, 09:01 PM
+4 ATF is really good for air adjustable forks though. I ran it on my old YZ and did not have any blowouts until I sold it.
NINJA
03-31-2010, 12:10 AM
"I was told by a head mechanic at a honda dealer that ATF is old school and fork oil has special conditioners to keep the seals softer and last longer and seal better."

I am a head mechanic and worked for years at a Honda dealer. Fork seals last just as long with ATF. How often do you have to replace seals in your cars automatic transmission?
Racerguy381
03-31-2010, 12:20 AM
It actually swells up rubber seals... Great fix for noisy hydraulic lifers in a car before you change the oil...