UPDATE ATF viscosity

[John Orchard]

Further to my post about fork oils, I just learnt the following...

All ATF (Automatic Transmission Fluid) marked as 'Dexron III has an ISO viscosity of 37.5 @ 40 degrees and 7.7 @ 100 degrees (This was shown in the previous mentioned thread .

New info is the new ATF marked DEX-VI, this is a new oil produced from 2006 onwards, it has an ISO viscosity of 30.0 @ 40 degrees and 6.0 @ 100 degrees (cSt).

So just warning you that Dexron VI is thinner than Dexron III  :-)

See  http://forum.ozvmx.com/index.php?topic=36800.msg356798#msg356798 for my original post.

[John Orchard]

If anyone is interested in an ISO/SAE cross-reference chart to see how various brands of fork/shock oil brands compare to hydraulic oil ratings. I can email one to you.

[Wasp]

ATF  means Automatic Transmission Fluid . Thats what it is designed for .

[oldyzman]

Hi Walter,
Have you tried ATF and found it to be not suitable? Just curious - i guess you would have some sort of shock testing machine.

[ghostdancing]

..just my little contribute.. ATF oil contains anti-foam additives, and that is needed in both automatic transmissions and forks..

it's simply a mineral oil plus anti-foam components; note also that honda suggest to use ATF in the forks of many older bikes like XL600 r, early XR600r and many other

i had the suspect that highly priced forks oils are actually mineral oil with anti-foam components, i.e. ATF bottled in super nice bottles

[skypig]

We used to use it in 2 stroke transmissions (and clutch)
Always worked fine. Is this practice out of favour with the common availablity of specialized products? (Quite possibly the same oil in fancy packaging also)

[pokey]

its mineral  but its not a basic motor oil. basically its anti foaming for hydraulic use..  It will work to an extent in other applications but its best left in an auto transmission as it does have limitations for lubrication and temperture fluctuations. if it was meant to be used in other applications the manufacturer would have specified as they are pretty cliuey guys.

[80-85 husky]

ive used it in the husky for some time with no worries. need to use the atf - f borg warner auto oil

[Nebo]

   
  WASP is correct. ATF is ATF.  Johnny O clearly has no Mechanical Engineering or Petroleum Engineering knowledge.

  A very important thing called Oil Sheer. Look the subject up . You may change your mind about using ATF.


  Also when you next time pull apart your gearbox because it jumps out gear or does not shift correctly.

  You may wonder way the hardening has come of the gears and the dogs are rounded on the gears.

   ATF OK in some Forks. Factory Teams used it get a little extra Hp lost in the gear box. Gear life not a issue.

[John Orchard]

   
  Johnny O clearly has no Mechanical Engineering or Petroleum Engineering knowledge.

   ATF OK in some Forks. Factory Teams used it get a little extra Hp lost in the gear box. Gear life not a issue.

Why you say that for?  I was only quoting cSt figures.

[sleepy]

I was told years ago by a my university lecturer that ATF was quite a good choice for motorcycles. He was a Tribologist (lubrication engineer) and his explaination was that a car auto is made up of wet clutch packs and gears and the oil has high pressure additives for the gears. May not be designed as a motorcycle gear oil but it does tick all the boxes and I have used it in various bike boxes for many years without issues.

[roon]

alert - oil war imminent - apply protective coatings and stand back :-) 

[Momus]

   
  WASP is correct. ATF is ATF.  Johnny O clearly has no Mechanical Engineering or Petroleum Engineering knowledge.

  A very important thing called Oil Sheer. Look the subject up . You may change your mind about using ATF.

Nebo, what are your engineering qualifications?
  Also when you next time pull apart your gearbox because it jumps out gear or does not shift correctly.

  You may wonder way the hardening has come of the gears and the dogs are rounded on the gears.

   ATF OK in some Forks. Factory Teams used it get a little extra Hp lost in the gear box. Gear life not a issue.