Best Transmission Oil for Harley 6 Speed: [Top 5 Picks]

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Harley Davidson is one of the most renowned bike manufacturers in the industry. The speed is the one thing that elevates its glory even further. Most riders prefer to use the 6-speed gear. And that makes it critical for you to get the best transmission oil for Harley 6 speed for better efficiency.

A good transmission oil ensures proper lubrication in the interior components of your bike. Also, it helps to decrease engine heat and make smoother and quieter transmissions.

However, there are so many different brands and models of transmission oil available out there. To help you pick the best one, let’s go over the top 5 transmission oil for 6 speed.

Best Transmission Oil for Harley 6-Speed

Let’s review the top 5 transmission oils that you can get for your Harley bike that’s going to be perfect for 6-speed.

1. Spectro Oil R.HDPG6 Heavy Duty Platinum Full Synthetic

Spectro Oil R.HDPG6 Heavy Duty Platinum Full Synthetic 6spd Trans Lube 1 Quart
112 Reviews
Spectro Oil R.HDPG6 Heavy Duty Platinum Full Synthetic 6spd Trans Lube 1 Quart
  • Cures noisy six speed transmissions
  • Smoother shifting, reduces fifth gear whine and eliminates clunks
  • G4 technology, special additives that provide additional anti-wear protection, higher film strength between the gears, and reduces drag while extending gear life
  • High loads and extreme heat do not affect the oil
  • A.P.I. Gl-5 rated. Dyed Red. Exceeds all known OEM and Harley Davidson warranty requirements

If you are looking for one of the best transmission oil for your Harley Davidson for 6 speed, this oil is going to do the job perfectly for you. It’s super-premium quality synthetic oil that’s going to improve the performance of your bike by a lot.

Another great thing about this oil is that it eliminates the noise that your 6-speed transmissions make. It helps to make the whole thing a lot smoother and efficient as well.

The best thing about this oil is that it can withstand high temperatures and don’t lose quality. That way you can use it for a very long time without any problem. That’s perfect for you if you want to go on an uninterrupted long ride.

It might be a bit expensive to get this oil, but it’s worth every single penny. It’s going to help to maintain the health of the engine of your Harley Davidson.

Also, it’s going to give you a smoother riding experience as well with your bike. So, if you’d like to have a premium quality synthetic oil for your Harley Davidson, you can go for this one. It’s a solid option for you and you are going to love the quality that it provides.

👍 Pros:
  • Best transmission oil for Harley Davidson
  • Gives smoother and quieter transmission
  • It can withstand higher temperatures
  • Best value of your money
👎 Cons:
  • Not the most affordable option

2. Maxima Racing Oils 90-119016C Chrome 90-119016C Twin Cam Synthetic

Maxima Racing Oils 90-119016C Chrome 90-119016C Twin Cam Synthetic 20W-50 Chrome Filter Complete Oil Change Kit, 6 Quart, 1 Pack
128 Reviews
Maxima Racing Oils 90-119016C Chrome 90-119016C Twin Cam Synthetic 20W-50 Chrome Filter Complete Oil Change Kit, 6 Quart, 1 Pack
  • Fits All 1999-present Harley Davidson Twin Cam engines; Meets or exceeds all manufacturers' specifications and will not void your new vehicle warranty
  • Contains 4 quarts of Maxima V-Twin 100% Synthetic 20W-50 Engine Oil, 1 quart of V-Twin Mineral Transmission 80W-90 Oil, & 1 Chrome 171C Oil Filter
  • Maxima V-Twin 100% Synthetic Engine Oil is an ester based motorcycle oil engineered and approved to be used as a multi-compartment oil for H-D V-Twin engines
  • Maxima V-Twin Transmission 80W-90 Oil is a high-quality, mineral based motorcycle gear oil. Recommended for use in 4-, 5- and 6-speed high performance gear boxes
  • Maxima V-Twin Primary Oil is a high-quality, mineral based motorcycle gear oil formulated for high-performance transmissions and primary chain cases

This is another great option for you if you are searching for a great synthetic oil for your Harley Davidson. It gets the engine at its maximum efficiency at the 6-speed transmission and helps to do the whole thing without any issue.

It features 20W-50 viscosity, which makes it perfect for both colds and hot temperatures. That way you can use it anywhere without any issues.

It gives you a very amazing mileage so that you don’t have to change the oil frequently. That’s perfect for you if you don’t want any interruptions in your long rides.

Another great thing about this oil is that it helps to maintain the health of your bike engine. It’s very slippery and that allows it to help the whole transmission process. Also, it eliminates the annoying noise as well, and that comes handy most of the time.

So, if you’d like to invest in a premium transmission oil for your Harley Davidson for 6 speed, you can’t find any better option than this one. It is going to guarantee the best quality and services that you can ever ask from in transmission oil.

👍 Pros:
  • Great for the health of your bike’s engine
  • Gives a very impressive mileage
  • Helps to reduce noise production by a lot
  • Keeps up the quality at both cold and hot temperatures
👎 Cons:
  • You might need to get more oil to fill up the tank

3. Life Guard Fluid 8 – ZF PARTS – S671090312

Life Guard Fluid 8 (7 Liter) - ZF PARTS - S671090312
42 Reviews
Life Guard Fluid 8 (7 Liter) - ZF PARTS - S671090312
  • Brand New ZF PARTS Lifeguardfluid 8, 7 Piece Set
  • BMW OE#: 83 22 2 220 443
  • ZF PARTS #: S671-090-312

ZF has some of the best fluid products that you can use for your engine that’s going to give you the best performance. This one is one of their best selling products that you can use for your Harley Davidson.

This oil is perfect for 6-speed transmission as it helps the engine to do the transmission a lot easier, smoother, and more quietly. It helps to improve the functionality and performance of your bike and make it work at its best capacity.

However, it’s a bit pricey, but if you don’t like to compromise the quality for the money, you are going to love this one. It has all the high-quality materials that you need to get maximum efficiency out of your bike engine.

If you want more power and mileage with your transmission oil, you can’t go wrong with this oil. There is no better transmission oil that you can find on the market at its price range.

So, if you are thinking about investing a bit more money for getting the premium quality transmission oil for your Harley Davidson, this one is going to be the best fit for you.

👍 Pros:
  • The most premium quality transmission oil
  • Helps to improve efficiency and performance
  • Makes the transmission a lot smoother and quieter
  • Best value of your money
👎 Cons:
  • Not the most affordable option out there

4. RAVENOL J1D2113 ATF

RAVENOL J1D2113 ATF (Automatic Transmission Fluid) - 8 HP 8-Speed & 6-Speed Compatible with Replacement for ZF Transmissions (1 Liter)
2 Reviews
RAVENOL J1D2113 ATF (Automatic Transmission Fluid) - 8 HP 8-Speed & 6-Speed Compatible with Replacement for ZF Transmissions (1 Liter)
  • Please see Product Description regarding the California Proposition 65 Warning
  • Controlled friction properties equals smooth and efficient shifting over the fluids life ,High viscosity index assures proper lubrication in severe hot and protection in cold weather; Good protection against foam formation with excellent cooling capacity
  • Excellent lubricating ability for the transmission even at low temperatures, provides a high, stable viscosity index, and good oxidation stability along with excellent protection against corrosion and foam formation
  • Excellent anti-wear, corrosion resistance, oxidation, and thermal stability
  • Note: See “Product Information/Technical Details/OEM Part Number” section in this product listing for OEM Approval details, OEM part numbers, oil specifications descriptions and quality standards for this product

If you are looking for a good quality transmission oil that’s not going to break the bank for you, this one is going to be a perfect fit in that case. It makes the transmission a lot smoother and efficient, and it’s perfect for 6-speed transmission as well.

The high viscosity lets this oil be the most effective at both the cold and the hot weather. That way you don’t have to worry about the environment you’ll ride your bike in.

Also, it’s very effective at keeping the engine cool as well. That way your engine gets more longevity and efficiency as well.

It features a lot of additives that help to keep the engine clean of all the corrosion and debris. And that’s perfect as it doesn’t require you to do extra maintenance to keep everything functional. Also, it provides decent mileage which is perfect for a hassle-free experience.

So, if you are searching for a great transmission oil for your Harley Davidson bike, this one is a no brainer option for you to get. You are going to get the most value out of it as it’s one of the best products at its price range.

👍 Pros:
  • Great quality transmission oil
  • Helps to reduce the noise of your engine
  • Keeps the engine clean of the debris and corrosion
  • Works amazingly at both hot and cold weather
👎 Cons:
  • Not the best option for you if you want greater mileage

5. Red Line RED42804 V-Twin Transmission Oil

Red Line RED42804 V-Twin Transmission Oil, 1 Quart, 1 Pack
714 Reviews
Red Line RED42804 V-Twin Transmission Oil, 1 Quart, 1 Pack
  • CUTTING EDGE TECHNOLOGY - Shockproof technology designed to make a big impact against big impacts
  • QUIET SMOOTH SHIFTING - V-Twin Transmission oil dampens transmission noise, reducing the notorious shifting clunk found in these gearboxes
  • IMPROVES PERFORMANCE - Transmission fluid that dramatically reduces temperature, providing thicker oil films between gear teeth and resists throw-off
  • SPECIFICALLY ENGINEERED - Gear oils designed for the latest high-revving four-stroke motocross bikes & ATVs sportbikes
  • WHY RED LINE - Established in 1979, Red Line Products perform & protect better than any on the market. No compromises

The final transmission oil we are going to review is a great option for your Harley Davidson for 6 speed. This is one of the best selling transmission oils by Red Line that you can get for a very affordable price.

It uses shockproof technology that makes this oil the perfect fit for your Harley Davidson. Especially this helps to make the engine stay healthy at the 6-speed transmission.

This oil helps to give you a quiet and smooth shifting that you crave. It is super slippery, which allows it to make the engine more effective and cut down the nose of shifting as well.

It helps to improve the overall performance of your bike, which is truly impressive for a product at its price range. It’s very easy to use as well and you won’t have to sweat to get the oil into place and to make your bike ready for a ride.

So, if you want to get the best quality transmission oil at a great affordable price, you can’t go wrong getting this one for your Harley Davidson.

👍 Pros:
  • Helps to improve the overall performance
  • Enhances the functionality and efficiency of the engine
  • Very easy to use
  • Best value of your money
👎 Cons:
  • Not the best option for warmth

Buying Guide For Harley 6 Speed Transmission Oils 

Now you have a list of the top 5 transmission oils that you can get for your Harley Davidson for 6 speed. But still, you need to consider a lot of things before you choose an oil for your bike. That’s going to ensure that you get the best fit for yourself and get the best value out of your money as well.

To help you with that, let’s go over everything you need to know and consider before you choose to spend your money on a transmission oil for your Harley Davidson 6 speed.

Type

You’ll find two main types of transmission oil that are very popular in the market; standard & synthetic.

Natural oil is not the best option for your Harley Davidson bike that you can get for your money. These are pretty annoying as you’ll have to change it very frequently to keep everything functional. Also, they don’t provide quiet operation or even good efficiency.

But that’s not the case with synthetic oil as you can use it to get more mileage. You won’t have to change anything to keep your engine at its peak using synthetic transmission oil. It is very slippery and provides a quiet service. It’s much more effective and efficient for your engine as well.

So, if you want to get the best oil for your Harley Davidson, you should get yourself synthetic oil over the standard oils. It’s going to ensure that you get the best possible results with your bike engine.

Viscosity

This tells you how faster or slower the transmission oil is going to flow inside the engine, and it’s a very vital thing that you need to consider before spending your money on oil.

Low viscosity means that the oil is going to flow faster and more freely inside and the opposite is accurate as well. However, you must choose the right viscosity level as it’s one of the most critical things you need to get right to keep your engine working.

Also, try to go for a viscosity that has a wider range. That’s going to be perfect for every environment whether it is cold or hot.

Additives

The next vital thing that you need to consider while you go to buy a transmission oil for your bike is additives of the oil. That’s going to impact the whole functionality of your bike.

The additives are very important to keep the engine clean and debris free. It’s going to help to keep it cool and function well in all environments as well, which is amazing for your Harley Davidson.

So, make sure to check the additives of the oil before you choose to spend your money on it.

Compatibility

The final thing you need to consider which is the most important thing as well is the compatibility of the oil. That’s going to tell you if the oil is going to be effective for your bike engine or not. Make sure to always check the compatibility of the oil to avoid any imbalance that can ruin the engine.

FAQ

Question 1: Should I get standard oil or synthetic oil for 6-speed transmission?

Answer: Synthetic oil is a far better option than a standard oil for so many different reasons. First of all, you can’t get enough mileage out of standard oil, and you’ll have to change it very frequently. That can be a huge interruption to your long rides and such. And another huge drawback is that it’s not good for every weather condition as well.

However, synthetic oil on the other hand is perfect for any kind of weather condition. Also, you can ride your bike for hundreds of miles, but you won’t have to change the oil, which is very impressive. And it’s far better for your engine as well.

Question 2: Are synthetic oils truly multifunctional or is it just a myth?

Answer: Synthetic oil can be a multifunctional oil if you know the right place to use it. First of all, you can use it on the bike chain, clutch, and engine, which is pretty impressive on its own. Also, it can be a great liquid that you can use to protect the brakes and the gear of your Harley Davidson.

It helps to reduce noise very effectively if you use it on the teeth of the gears. That way the gear shifts will be very less noisy and also it’s going to stay healthy for a long time.

Question 3: Is there any time when I should not use synthetic oil on my Harley Davidson?

Answer: It’s perfectly fine to use synthetic oil on your Harley Davidson at any time without any trouble. You should know that synthetic oil is very slippery and provides maximum efficiency to the engine of your bike. That way the overall performance of your bike improves by a lot.

It’s a far better option than using a standard oil in your Harley Davison bike. That’s going to ensure that everything works at maximum efficiency at all times.

Final Thoughts

Now that you have a list of the top 5 best transmission oil for Harley 6 speed that you can get from the market. Also, the in-depth buying guild will help you further to pick the perfect fit as well.

Just make sure to spend as much as you can afford to get a better quality transmission oil for your Harley bike. That’s going to pay off big times in the near future for you.