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For all you Syn 3 users, the motor company has sent us new guidelines for changing Syn 3 oil. If you use Syn 3 oil in your VTwin the engine oil should be changed every 5000 miles, in your primary it should be changed every 10000 miles, and in your tranny it should be changed every 20000 miles. For you VRod riders, you should continue to follow the 5000 mile rule. This should help keep down the cost of you service at 5000 mile intervals. What do you think about the new fitment? Would you go 20000 miles before you change your tranny oil, and 10000 miles before you change your primary?
Lets here from you.....
For all you Syn 3 users, the motor company has sent us new guidelines for changing Syn 3 oil......snip...... What do you think about the new fitment?.......
I think there are many more synthetic lubricants on the market that will outperform SYN 3.
Personally, as long as Amsoil and Redline are available, I wouldn't even use SYN 3 in my lawnmower.
It sounds reasonable to me. By using some of the higher quality oils, such as Mobil 1 red cap or V-twin, you should be pretty safe at 5K intervals for the engine oil. The others seem long to me, but I have nothing concrete to back that up.
Problem is, oil change intervals are very personal decisions and it seems not too many people believe either the MoCo or the oil companies. This thread should become pretty lively.
I don't see too much of a problem with those intervals. I've gone a year on the same primary fluid before, probably about 15k miles, and it wasn't a synthetic. Also gone quite a spell on the same tranny juice. It would get changed when too much water vapor would condense out and turn it white.
I was wondering about something. If a person went to the dealer to have his Harley serviced and they followed the recommendations of the mechanic on doing the oil change and what to use, wouldn't the dealership be responsible if something went wrong with the bike?
This sounds resonable to me, the engine oil needs to be changed more often becuse of contamination from combustion byproducts. As there are none of these in the trany or primary case the oil can maintain it's lubricating properties.
As far as Syn 3 not being as good as other synthetics, remember Harley doesn't manufacture oil. There was a point in time when Sunoco was there supplier but as Sunoco has no synthetic my guess would be it's repackaged Mobil 1 V Twin. And no other oil has been tested by Harley in their engines I believe it's as good as any other quality brand. The two mentioned here are also excellent oils, I have KLR650 that I use Amsoil in and it works fine.
DC
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HDs Syn 3 ain't Mobil 1. Sunoco is still the supplier on the HD dino oil, as you indicated. Somewhere on here there are results from analyses of new Syn 3 20w-50, Mobil 1 V-Twin 20w-50, Mobil 1 15w-50 gold cap. & Mobil 1 MX4T 10w-40. The Syn 3 came out at the bottom of the pack as far as its overall additive package. Also Syn 3 is a Group 3 synthetic, meaning it is still refined from dino oil, while the Mobil 1 is a Group 4 synthetic, meaning that it is constructed from scratch with polyaolefin base stock. Castrol synthetic is a Group 3; AMSOIL is a Group 4; not sure about Redline.
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