Can anyone tell me what the basic difference is between ATF fluid and engine oil? And I know one is red.
ATF vs ENGINE OIL
- Thread starter MULESKINNER
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Viscosity wise, ATF is around a 5W20. The main difference is the additive package. Engine oil has a lot more additives in it to deal with an internal combustion engine. ATF works more like hydraulic oil and does not take near the abuse as engine oil does.
Hope that helps.
Hope that helps.
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Standard ATF (Mercon/DexronIII, etc) is generally in the 7cSt range.
The additive package is completely different between motor oil and transmission fluid. Transmission fluids are generally blended to be strong on dispersants rather than detergents.
And of course transmissions need extreme pressure additives that engines don't need and they need to be compatible with a more diverse roster of seals and friction materials.
The additive package is completely different between motor oil and transmission fluid. Transmission fluids are generally blended to be strong on dispersants rather than detergents.
And of course transmissions need extreme pressure additives that engines don't need and they need to be compatible with a more diverse roster of seals and friction materials.
Most ATF will be around 35 cSt @40c, which would be in the low 20 wt, high 10 wt engine oil vis.
I think we will find that ATF will have little to no detergent and dispersant, due to the transmission being a closed system that sees no soot and carbon that needs collection and suspension, as an engine would.
I also think you will find that the lubricating components aren't too far off from engine oil components. ATF does not have lots of "detergents and lubricity additives that engine oil doesn't contain".
I think the other way around would be more correct, Dom.
I think we will find that ATF will have little to no detergent and dispersant, due to the transmission being a closed system that sees no soot and carbon that needs collection and suspension, as an engine would.
I also think you will find that the lubricating components aren't too far off from engine oil components. ATF does not have lots of "detergents and lubricity additives that engine oil doesn't contain".
I think the other way around would be more correct, Dom.
I don't know about their requirements now, but back in the 1950's and possibly in the 60's, the California Highway Patrol required that any car they bought for their fleet had an automatic transmission that was compatible with the same oil used in the engine.
The reason I asked this question, is some folks are using ATF for their primary drive chain case on Harley Davidson bikes. The chain case is closed with no exposure to the engine oil. The clutch is contained in the chain case and lubricated by the same fluid. I still can not get a straight answer out of them why they are using ATF rather than the 15/50 engine oil HD specs for the chain case.
heres a reasonably straight answer.
auto trans have clutches, gears, chains, bearings, shafts and oil seals just like a harley primary. so you could consider a harley primary to be an automatic transmission without the "automatic" and torque converter. they are reasonably similar.
these people figure that a thin atf would probably work better than a thicker oil.
its that simple.
auto trans have clutches, gears, chains, bearings, shafts and oil seals just like a harley primary. so you could consider a harley primary to be an automatic transmission without the "automatic" and torque converter. they are reasonably similar.
these people figure that a thin atf would probably work better than a thicker oil.
its that simple.
I used Redline MTL for the past two years with no detrimental results. The clutch feels a little "lighter" I guess is the best way to put it. Neutral is very easy to find, although it was not hard with either the stock fluid or Amsoil 10W-40 either. Shifting is very easy at 5000+ rpm and normal shifts are smooth and quiet. I am trying Amsoil ATF next season to further experiment. At worst my clutch plates will fail and I will just put a high performance clutch in and start over w/o ATF. I really doubt that will happen though. As explained above by Master ACiD, you just won't find anything in the HD primary that you don't in the millions of automatic transmissions on the road today, except for the alternator, although most transmissions have electronics inside of them. I don't believe the ATF will attack the windings so it should not present any problems in that regard.
I was just reading an article in Easyriders about Sturgis and how there were less people there this year, perhaps because a lot of the "new" riders of the past few years have given up riding because the Biker Builder shows are not as prevalent as they were and the "sport" is not as popular because of it. Perhaps HDs big push to have one lubricant for every hole was to make it easy on people who have little riding and/or mechanical background? I personally believe that many compromises are made when trying to provide a be-all-end-all lubricant and therefore each sump gets a different product on my bike. ATF just makes sense to me for the primary. I can't think of a reason why NOT to use it. If someone has a good reason, I'm all ears.
I was just reading an article in Easyriders about Sturgis and how there were less people there this year, perhaps because a lot of the "new" riders of the past few years have given up riding because the Biker Builder shows are not as prevalent as they were and the "sport" is not as popular because of it. Perhaps HDs big push to have one lubricant for every hole was to make it easy on people who have little riding and/or mechanical background? I personally believe that many compromises are made when trying to provide a be-all-end-all lubricant and therefore each sump gets a different product on my bike. ATF just makes sense to me for the primary. I can't think of a reason why NOT to use it. If someone has a good reason, I'm all ears.
The ATF in the HD primary case works well because of the wet clutch.
Thick sauce would be to hard to squeeze out, and there would be slippage.
Thick sauce would be to hard to squeeze out, and there would be slippage.
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