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ATF Dextron in primary, is synthic better to run in that hole ?

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Old Feb 5, 2010 | 10:06 AM
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Default ATF Dextron in primary, is synthic better to run in that hole ?
I have a question about Dextron ATF in the primary . is there a benifit to running a synthic Dextron ATF in the primary over regular Dextron ATF?? I run a 1996 FXDWG evo. I have run ATF in the primary for a million years.
 
Old Feb 5, 2010 | 10:10 AM
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Did milk the dinosar for oil back then a million years ago.
 
Old Feb 5, 2010 | 10:25 AM
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Old Feb 5, 2010 | 10:27 AM
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To old for myself.
 
Old Feb 5, 2010 | 10:52 AM
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Be aware that putting synthetic in a million year old bike will bring out the false seal problem.
 
Old Feb 5, 2010 | 11:51 AM
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I use Mobil 1, V-Twin, synthetic, in my primary. Maybe it will add a little bit longer life to the tensioners.
Tom
 
Old Feb 5, 2010 | 11:55 AM
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Originally Posted by blair
I have a question about Dextron ATF in the primary . is there a benifit to running a synthic Dextron ATF in the primary over regular Dextron ATF??...
It has been suggested that synthetic ATF will withstand somewhat higher temps when compared to the regular stuff.

I've used both with the same perceived results.
 

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Old Feb 5, 2010 | 12:09 PM
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If you've got high enough temps in the primary to need syn oil, you've got problems syn oil won't help.
ATF withstands the temps in an automatic transmission, so it's over-qualified for use in the primary.
 
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Old Feb 5, 2010 | 12:18 PM
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Originally Posted by mp
If you've got high enough temps in the primary to need syn oil, you've got problems syn oil won't help.
ATF withstands the temps in an automatic transmission, so it's over-qualified for use in the primary.
Bare in mind that the primary acts like a heat sink. In some places with OAT's and idling traffic, engine oil temps can exceed 300F and that, in turn, adds significant heat to the primary.

In those conditions, synthetic ATF in the primary is certainly not "over qualified" by any stretch.
 
Old Feb 5, 2010 | 12:50 PM
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Maybe I'm just stupid, I run what the manual says: Harley primary oil. Been doing that for a LOT of years.
 



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