Just wondering how many others have run into SYN3 lubricant issues.
2011 FXDF 110ci motor, used SYN3 since new. 12 miles on motor when picked up. All maintenance and service intervals done by Harley dealers.
@ 54,000 miles
Transmission failure - Main roller bearing failed - taking out 4 & 5 gears, shifted the armature causing the main drive belt and both pullys to fail.
repair cost $2.400 CAN (of course it happened in the middle of a road trip to Nova Scotia)
@ 57, 000 miles
Lifters failed - still waiting on all the issues from this repair to come in.
Figured I'd join the Forums and see if there is anyone else experiencing issues like this with SYN3 use. I have heard a lot of talk of SYN3 causing these issues from Harley Technicians and Service professionals all up and down the east coast and Canada but no one will take a stand against SYN 3 use or recommend against it. Makes sense in the context the information was provided - at the dealerships.

 

I've read plenty of posts here where owners have used that oil with no problems. I'm sure they will chime in.
Personally, I'm not a believer that a single oil can be the best choice for each application, regardless what the MOCO says. So I use motor oil, primary oil and trans oil designed for those uses. It's not that much of an inconvenience.

 

I use Redline products in all 3 holes...20w50 in engine, their trans fluid with shockproof in the tyranny and their primary fluid...I think they make a great product...just my opinion

 

Exactly, engine oil makes a horrible trans and primary lube. It has none of the anti-shear additives that real gear lube have. Harley knows you are paying them to dump it once a year, at least, and they make huge money selling "synthetic fluid changes". I have a lot of experience with it, both in dealerships and racing, it is not a very good product compared to many out there. I will just use Royal Purple as an example, without the desire to start yet another debate about oil.

 

There are so many unknown variables here. How many miles per oil change and was the correct filter always used?

 

New 2017 road king owner. Was thinking about this today.
Had liked the idea of a synthetic. But seemed a little thin for trans and primary.
Think I;ll have them do the regular 1k service with standard stuff and change it over myself. Dedicated trans and primary fluids.

 

I would "NEVER"run motor oil in a tranny,don't care what the moco says.as far as syn 3 goes,i believe its produce by citgo i can't imagine its better or worse then any other synthetic in its class,key word here is "in its class".there are many better oils out there for one to choose from.

 

Chances are your Harley lifters would have failed with any oil.... lots of history there.

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So you think a 75W 90 is better? Now here is the shocker it is the same viscosity as a 20/50 engine oil. They use two different methods to measure them. If the same is used they 75W90 gear oil and 20/50 engine oil come out the same.
No way on this earth 20/50 syn oil is to thin. In fact to thick is a bad idea all of today engine ,transmission are designed for lighter lubes.

 

engine oil regardless of how the viscosity is checked does not have the additives that trans oil does.yes to heavy is a factor even in harley transmissions,but the trans oil has to have the anti shear and throw off properties.in other words,the oil must stay on the teeth while meshed and stay on the teeth at high rpm's to create a cushen.at least thats the theory as to how its suppose to work.engine oil does not do this effectively.