SYN-3
Elite HDF Member
Joined: Oct 2005
Posts: 3,872
Likes: 83
From: Canton, Michigan
RE: SYN-3
I had to switch to Syn-3 in the primary because the regular Harley dino stuff was no longer available. I've developed a 'whirling' noise about 500 miles after the swap. Don't know if it's from the oil or not. I might try something different the next scheduled change.
For the transmission I'm nowusing Mobil 1 gear oil (same deal, couldn't find the HD semi-syn). I don't really notice a difference from the stock HD semi-syn oil I used prior. But then, my 93 doesn't have any backcut gears, so it's rather noisey anyway. (I laugh everytime I read about the 07's with the 'noisey 5th gear'-hell the day I rode my 93 FLHShome from the dealer I thought I was in my old Peterbilt)
For the transmission I'm nowusing Mobil 1 gear oil (same deal, couldn't find the HD semi-syn). I don't really notice a difference from the stock HD semi-syn oil I used prior. But then, my 93 doesn't have any backcut gears, so it's rather noisey anyway. (I laugh everytime I read about the 07's with the 'noisey 5th gear'-hell the day I rode my 93 FLHShome from the dealer I thought I was in my old Peterbilt)
Cruiser
Joined: Sep 2006
Posts: 153
Likes: 0
From:
RE: SYN-3
My 98 FXSTC has had syn 3 in all three holes since it was new. With almost 50,000 miles, I changed to Mobil 1 oil and transmission lube (I have dyno oil in the primary). I have noticed a considerable difference (positive) in the way it shifts.
Stellar HDF Member
Joined: Feb 2007
Posts: 2,558
Likes: 280
From: Russellville, Arkansas
RE: SYN-3
I use regular 20w50 for summer months. HD360, TwinPower, Revtec, Castrol GTX, and other various aftermarket oils. Currently, it is has Valvoline VR1 and that is a pretty good oil.
The winter months...it gets 15w40 diesel oil. Rotella, Motorcraft, and other storebrand diesel oil.
The primary gets 15w40 diesel oil year round. I don't care who makes it.
The transmission gets 80w90 GL5. It has been regular, synthetic, and semi-synthetic. I don't care who makes this stuff either.
Absolutely no trouble and this way works for me.
The winter months...it gets 15w40 diesel oil. Rotella, Motorcraft, and other storebrand diesel oil.
The primary gets 15w40 diesel oil year round. I don't care who makes it.
The transmission gets 80w90 GL5. It has been regular, synthetic, and semi-synthetic. I don't care who makes this stuff either.
Absolutely no trouble and this way works for me.
Cruiser
Joined: Nov 2006
Posts: 193
Likes: 1
From: Arnold, MO
RE: SYN-3
I've been using Harley 20W/50 dino in the crankcase. Formula + in the primary. Just switched to Mobil 1 75W/140 in the tranny. The Mobil 1 made a huge difference. Really quieted the tranny down. Sixth gear is almost quiet now.(aftermarket)
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Ultimate HDF Member
Joined: Apr 2006
Posts: 6,913
Likes: 87
From:
RE: SYN-3
ORIGINAL: EVOrider
I use regular 20w50 for summer months. HD360, TwinPower, Revtec, Castrol GTX, and other various aftermarket oils. Currently, it is has Valvoline VR1 and that is a pretty good oil.
The winter months...it gets 15w40 diesel oil. Rotella, Motorcraft, and other storebrand diesel oil.
The primary gets 15w40 diesel oil year round. I don't care who makes it.
The transmission gets 80w90 GL5. It has been regular, synthetic, and semi-synthetic. I don't care who makes this stuff either.
Absolutely no trouble and this way works for me.
I use regular 20w50 for summer months. HD360, TwinPower, Revtec, Castrol GTX, and other various aftermarket oils. Currently, it is has Valvoline VR1 and that is a pretty good oil.
The winter months...it gets 15w40 diesel oil. Rotella, Motorcraft, and other storebrand diesel oil.
The primary gets 15w40 diesel oil year round. I don't care who makes it.
The transmission gets 80w90 GL5. It has been regular, synthetic, and semi-synthetic. I don't care who makes this stuff either.
Absolutely no trouble and this way works for me.
Why do you use diesel oil?
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