Synthetic Oil

Oil of Choice

  • Castrol Syntec/Edge

    Votes: 235 8.5%
  • Royal Purple

    Votes: 326 11.8%
  • AMSOil

    Votes: 398 14.4%
  • Valvoline Synpower

    Votes: 160 5.8%
  • Mobil 1

    Votes: 993 35.8%
  • Other

    Votes: 661 23.8%

  • Total voters
    2,773

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Burla

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Kept running even with sump drained, but when pan was removed, 2 miles, lol. Just a little oil in the pan and it will run.
 

HEMIMANN

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Amsoil MCV works great. The only Red Line an H-D "needs" is Shockproof Gear Oil in the transmission. Amsoil SVG works, but RL was definitely better.

For some reason I haven't been getting push notes from Syn Oil Thd, missed a bunch. Maybe I'm banned?

Anyway, Harley claims their new branded heavy synthetic manual transmission oil fixes the shift clunking and neutral hunting. Some riders say it really works.

I have RL Shockproof in my trans now, it helped, but neutral still gets tough to find. It seems to me the real difference is viscosity - Shockproof is 75W-90, Harley is 80W-140.

I'm not that familiar with Harley gear boxes, but I get the impression they've remained pretty crude - not even sure if they have synchros, hence the clunking. The trans isn't big either - that thing really takes a load and gets hot. I might try some of Harley's branded stuff......the trans only takes 0.8 quarts of oil!
 

HEMIMANN

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I run AT 4 Mobil 1 in my Motorcycle due to my all in one oiling. Nothing under 10-40 too hot in summer. But I have to have amount in crankcase exact. Even less than 1/4 qt overfill get blow back from pcv crankcase blow by valve

GW is water cooled - runs cooler and easier on the oil.

I still like the throw back air cooled Harley V Twin though. Can stretch my legs out without jugs sticking out the sides. So I go all the way to Group IV / V on these kinds of high load, high temp engines.

I run either Red Line or Amsoil in the engine. I only put enough miles on to change once a year, so I guess the pricing isn't a killer for me, but the touring guys - ouch!

These newer air cooled Harley's have the M8 engine. 4 valve heads, and oil cooled heads. They don't run quite as hot as the non oil cooled heads of yore. I got an oil temp dipstick. The sump oil reads 200 degrees F when run hot in high summer ambients. That's well-done air cooling.
 

JHoward

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For some reason I haven't been getting push notes from Syn Oil Thd, missed a bunch. Maybe I'm banned?

Anyway, Harley claims their new branded heavy synthetic manual transmission oil fixes the shift clunking and neutral hunting. Some riders say it really works.

I have RL Shockproof in my trans now, it helped, but neutral still gets tough to find. It seems to me the real difference is viscosity - Shockproof is 75W-90, Harley is 80W-140.

I'm not that familiar with Harley gear boxes, but I get the impression they've remained pretty crude - not even sure if they have synchros, hence the clunking. The trans isn't big either - that thing really takes a load and gets hot. I might try some of Harley's branded stuff......the trans only takes 0.8 quarts of oil!

Thanks for that, I'm going to use RED Line Shockproof and Red Line V Twin oils on my upcoming oci.

I've been using Mobil 1 20w/50 V-Twin oil for engine and primary and Mobile 1 75w/90 Gear oil for the transmission for oci's. My machine is 14 years old now and it wouldn't hurt for a little more and better protection using Red Line oils.
 
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turkeybird56

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2019 Bighorn, 4 X 4, 3.21 rear, Bright Flame Red Pearl Coat, Mopar tonneau cover,Westin Bed rug
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Hemi 5.7
GW is water cooled - runs cooler and easier on the oil.

I still like the throw back air cooled Harley V Twin though. Can stretch my legs out without jugs sticking out the sides. So I go all the way to Group IV / V on these kinds of high load, high temp engines.

I run either Red Line or Amsoil in the engine. I only put enough miles on to change once a year, so I guess the pricing isn't a killer for me, but the touring guys - ouch!

These newer air cooled Harley's have the M8 engine. 4 valve heads, and oil cooled heads. They don't run quite as hot as the non oil cooled heads of yore. I got an oil temp dipstick. The sump oil reads 200 degrees F when run hot in high summer ambients. That's well-done air cooling.
I have Kawasaki Ice in the rads, but even with that, and the synthetic oil and filter of course, at over 100 F out, I could cook eggs off that heat from the motor. I change oil once a year as I do not put many miles on the "Golden Pig" also. I have a filter and 4 qts of oil in a cabinet in the garage, figure somewhere near April get it done.
 

turkeybird56

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For some reason I haven't been getting push notes from Syn Oil Thd, missed a bunch. Maybe I'm banned?

Anyway, Harley claims their new branded heavy synthetic manual transmission oil fixes the shift clunking and neutral hunting. Some riders say it really works.

I have RL Shockproof in my trans now, it helped, but neutral still gets tough to find. It seems to me the real difference is viscosity - Shockproof is 75W-90, Harley is 80W-140.

I'm not that familiar with Harley gear boxes, but I get the impression they've remained pretty crude - not even sure if they have synchros, hence the clunking. The trans isn't big either - that thing really takes a load and gets hot. I might try some of Harley's branded stuff......the trans only takes 0.8 quarts of oil!
I enjoyed my old 2008 HD Ultra Classic, but yeah, that old "CLUNK" when U hit 1st gear, that is a sound I do not MISS riding the Gold Wing. But my wing is a 2006 and still has the old ancient 5 speed in it with a half wind out 1st and a lower geared 5th. Wish I had a true 6 speed, but they did not come out till x x x amount of years ago. But get up around 75 MPH, put on cruise, fire up the jams (I have a BT receiver installed so I can stream wateva off of my I Phone), and it is just an enjoyable experience. I do not MISS the vibration either of the ole V Twin.
 
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HEMIMANN

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I enjoyed my old 2008 HD Ultra Classic, but yeah, that old "CLUNK" when U hit 1st gear, that is a sound I do not MISS riding the Gold Wing. But my wing is a 2006 and still has the old ancient 5 speed in it with a half wound out 1st and a lower geared 5th. Wish I had a true 6 speed, but they did not come out till *** amount of years ago. But get up around 75 MPH, put on cruise, fire up the jams ( I have a BT receiver installed so I can stream wateva off of my I Phone),. an it is just an enjoyable experience. I do not MISS the vibration either of the ole V Twin.

BOIRD - I still need the shake n' bake to keep me alive and alert.

Softail has the counterbalanced, direct-mount engine. Riders complain of drone resonance at certain speed combos, but I'd rather have this build than an unbalanced motor jumping around on rubbers. That's not a recipe for engine life. I know a lot about that topic from my big diesel powertrain design years.

btw, surely you know Honda has auto trans option now. Just sayin'. Spend some of that inheritance fortune! lol
 

turkeybird56

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BOIRD - I still need the shake n' bake to keep me alive and alert.

Softail has the counterbalanced, direct-mount engine. Riders complain of drone resonance at certain speed combos, but I'd rather have this build than an unbalanced motor jumping around on rubbers. That's not a recipe for engine life. I know a lot about that topic from my big diesel powertrain design years.

btw, surely you know Honda has auto trans option now. Just sayin'. Spend some of that inheritance fortune! lol
It's the kids gonna get and spend, my job is to put away, lmao. Yes, Honda has the 7 Speed DTC's that came out in 2018 ish. But my trike is a 2006 bike with a 2015 Kit. Not got any of the bells and whistles on the rides now. I did check in at DFW Honda, only place U can get a Built Honda Motor Trike unless U get from a 3rd party builder, and the 2023's were 56K +++ out the door, lol.
 

HEMIMANN

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It's the kids gonna get and spend, my job is to put away, lmao. Yes, Honda has the 7 Speed DTC's that came out in 2018 ish. But my trike is a 2006 bike with a 2015 Kit. Not got any of the bells and whistles on the rides now. I did check in at DFW Honda, only place U can get a Built Honda Motor Trike unless U get from a 3rd party builder, and the 2023's were 56K +++ out the door, lol.

You sell outright, plus you can ride longer there. Do it.
 

turkeybird56

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You sell outright, plus you can ride longer there. Do it.
NAH, TBH, I sent U PM wat I am doing now. Besides, TBH, I do not ride a lot any more since no longer in club and riding alone not all it is cracked up to be, and the big "PLUS", might be an 18 yoa bike, but only 56K on odometer and paid off, lol.

ADDED: I thought about trading up and going back to "2" wheels, BUT the Trike is just so much easier to ride and enjoy. Not been on "2" wheels since 2015, been on the Trike. And U do get lazy riding VS worrying about stuff like wind, drafts, putting feet down, parking in hot lots. THE thing I miss is counter steer and lean, of course those U cannot do. Besides, BOIRD not getting ne younger, argh....
 

MRFREEZE57

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For some reason I haven't been getting push notes from Syn Oil Thd, missed a bunch. Maybe I'm banned?

Anyway, Harley claims their new branded heavy synthetic manual transmission oil fixes the shift clunking and neutral hunting. Some riders say it really works.

I have RL Shockproof in my trans now, it helped, but neutral still gets tough to find. It seems to me the real difference is viscosity - Shockproof is 75W-90, Harley is 80W-140.

I'm not that familiar with Harley gear boxes, but I get the impression they've remained pretty crude - not even sure if they have synchros, hence the clunking. The trans isn't big either - that thing really takes a load and gets hot. I might try some of Harley's branded stuff......the trans only takes 0.8 quarts of oil!
What year is your Harley, on my 2014 FXDL that tranny shifts as smooth as a hot knife thru warm butter and simple to find neutral, on the other hand my 21 Road Glide Limited is noiser shifting and a bit more tricky to find neutral. I run Amsoil V Twin primary and their transmission oil in the Limited but the Dyna just use Formula + in primary and transmission. Not sure if any big changes in trans between 2014 and 2021, guess is just the nature of the beast.
 

TotallyHucked

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I would have my Hemi towed at this point in my life as well. I won't need to hope for the best, as I already have tested the limits.
I gave you a scenario that happened to me. Driving a Cheby 3500 Dirtymax pulling a trailer with 2 Ford Excursions on Thanksgiving at 0130 just outside Indianapolis In. I hear a noise and lose oil pressure. Decision time. Wait for tow-truck which buddy at 1 towing company charges $600 just to start up their tow-truck + mileage and Holiday premium. Would have equaled the cost of rebuilding Dirtymax anyway. I drove all the way to my shop in Dayton Ohio with no issues, pulling that loaded trailer.
After Thanksgiving weekend I installed new oil pump, refilled engine with new oil, oil filter and more Motorkote with zero harm to engine. That was back in '04. That Dirtymax is still on the road working harder than I ever dreamed of.
I know for a fact 1 of the 7 time Nascar Champions team used and still use this product in their race cars. This stuff is used in ALOT of racing Hemi's as well. alot of teams use this stuff and are tight lipped about it.
My '01 Ford XLT with 5.4 Triten, one of Fords hated engines is still running strong. My neighbors nephews truck was honored at Ford Sharonville Transmission Plant with exact same truck as mine. where all he did was maintenance and run Motorkote. Was honored for 1 million miles total stock truck.
I am speaking from real world experience. Not some lab tests done by some independent study to bash one product over another. I am happy for you that your oil set up works well for you. Like I said I would run your same set up with 1 exception. I would add Motorkote and roll on
Thank you JHoward for chiming in on this subject.
I'm gonna call BS on this too. There's no way. You might've had a sensor go bad or the gauge cluster decided to act up and showed no oil pressure (I've had many of those trucks, those clusters are always failing) but there's no way you towed that load 100+ mi with actual zero oil pressure. A mile downhill at idle just to get stopped, maybe.
 

marine0311

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I'm gonna call BS on this too. There's no way. You might've had a sensor go bad or the gauge cluster decided to act up and showed no oil pressure (I've had many of those trucks, those clusters are always failing) but there's no way you towed that load 100+ mi with actual zero oil pressure. A mile downhill at idle just to get stopped, maybe.
I really don't give a damn what you or anyone else thinks. I did it. I KNOW what I'm talking about. It wasn't a faulty gauge cluster either. As far as I am concerned, either believe me or pound salt. Go ahead and tar and feather me and try to send me out on a rail. I do not care
 
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