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What are the Best 3 Transmission oils for my Harley Davidson? This is perhaps one of the most common, and controversial questions asked by all Harley owners. It is not surprising because there are so many tranny oils to choose from, and you aren’t sure which is safe for your ride.
But you want the best oil that can reduce the accumulated engine heat. This is required because the Harley Davidson is an air cooled motorcycle that gets hotter quicker than a water cooled motorcycles. It is the right oil that helps ensure your Harley’s motor runs at optimal temperature.
Most important, you should know that you should never use motor oil for your engine and your tranny. Sometimes dealerships may state that single oil is more than enough for all your lubricating needs.
However keeping a high quality fully-synthetic 20W40 motor oil for the engine, a synthetic gear oil for the tranny and a synthetic gear oil for the clutch and chain is a much better practice which Harley owners, and other motorcyclists should maintain.
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What happens if you use motor oil in the transmission?
If you wonder what happens if you add motor oil to the transmission, well motor oil contains additives that keep contaminants suspended. This is not at all good for your pride and joy, which is there are specific tranny oils in the market. Here is a brief description of the three most popularly used oils in Harley Davidson motorbikes:
The Best 3 Transmission Oils for my Harley Davidson
1. Amsoil MYTQT-EA Synthetic V-Twin Trans Fluid, 1 qt.
What we like
- The synthetic oil can perform efficiently under any weather
- It does not void the warranty of your Harleys bike when you use it.
- You can never miss any shift when using the Amsoil MYTQT-EA synthetic oil which assures you of a perfect acceleration.
- It saves you a lot of maintenance cost and time
What we do not like
- It is not multifunctional which adds you more cost
Pros
Allows for smooth shifts
No rider wants to miss any shift while riding. You also want to have the best acceleration through all the gears. As such, Amsoil MYTQT-EA Synthetic V-Twin Trans Fluid, 1 qt is for you. The oil comes with viscometric and frictional properties that make it easy for you to shift from one gear to the next for optimal performance.
Additionally, the fluids protect your gear and bearings from wear and tear, thereby reducing gear noise and get rid of loud thumps. Thus, you have the assurance that your Harley Davidson Sportster, Softail or other model will respond as you wish and offer you a ride like no other.
Protects the gear and bearings from wear and tear
Every serious rider knows that there is extreme pressure between gear teeth as you ride. Not all fluids can stand the pressure, and some will lose viscosity and expose your gear and bearing to wear.
However, Amsoil MYTQT-EA SYNTHETIC V-TWIN Trans Fluid withstands the extreme pressures between gear teeth. It does not lose viscosity, and it can also withstand extreme temperatures. As such, it provides optimal protection against gear wear.
Apart from the extreme pressure additives that protect the gear and bearings from wear, the trans fluid also contains molecules that prevent damage from shock loading.
Less frequent oil change
As a rider, you want a tranny that will not only offer you optimal performance but also saves you maintenance costs. You do not want a fluid that will require you to go to the garage after a few weeks to change the oil.
As mentioned earlier, Amsoil MYTQT-EA trans fluid can withstand extreme pressures between gear teeth, and it also performs under high temperatures and doesn’t lose viscosity. Thus, you will have fewer intervals of going to the garage to change the oil, which saves and allows you time to carry out other chores.
Warranty secure
The last thing you want to put on your ride is anything that will void your warranty. Amsoil MYTQT-EA trans fluid gives you the security and confidence that you need for using it as it does not void your warranty in case of anything.
Performs well under extreme temperatures
With the Amsoil MYTQT-EA transmission fluid, you are sure that your ride will not disappoint you under any weather. It can perform optimally under high temperatures, and when the temperatures go down outside, your ride will still offer you maximum efficiency.
Cons
Not multifunctional
The fact that the Amsoil MYTQT-EA fluid is not multifunctional means you will incur more cost. You will have to buy different motor oil for your engine, the clutch and chain, and synthetic oil for the tranny.
A Little More Info
The Amsoil Synthetic V-twin Trans fluid is specially formulated for those drivers looking for a dedicated fluid for their Harley Davidson bikes, instead of something multifunctional. This oil helps give smooth shifting of gears and keeps transmission noise down. Regular use of it will lead to an improved clutch feel as it protects your gear, chain and bearings from wear and tear.
The Amsoil Tran fluid helps your ride function smoothly and quietly by forming a durable oil film on gears and bearings. It is this oil film which with time dampens any loud chunks produced while shifting gears.
This layer of oil also helps protect the tranny against possible gear and bearing wear and tear. It can also resist viscosity loss and withstand extreme heat which proves ideal for optimal wear protection. It is the strong molecules in the oil that creates a film which keeps the tranny protected from any damage inflicted by shock loads.
It is the combined efforts of all these features that help provide for smooth shifts and helps prevent riders from missing shifts. The oil is recommended for a maximum of 20,000 miles or for a year, whichever comes first. This oil is just right for bikers reluctant to use multi-use lubricants. And thanks to their wide range of products, Amsoil tranny oils appeal to most people.
2. Red Line 42804 V-Twin Transmission Oil
- This product dampens transmission noise (reducing the notorious shifting clunk found in these gearboxes), dramatically reduces temperature, provides thicker oil films between gear teeth and resists throw-off
- Compatible with all aftermarket versions like Baker, JIMS, S&S, etc.
What we like
- The pink color makes it stand out
- After every oil change, the magnetic drain plug is always clean with no metal shaving accumulated.
- Effortless shifting of gear
- The oil reduces temperatures significantly for optimal performance
- It does not void your warranty
What we do not like
- Some people may have an issue with the color
Pros
Dampens gearbox noise
For every rider, nothing disturbs more than a gearbox that sounds like it is going to fall off the next minute. Gearbox noise is occasioned by the use of oil that is not able to withstand the extreme pressure from the shifting gear teeth, especially for a sporting bike.
Red Line 42804 V-Twin trans oil comes with friction modifiers that help to reduce gearbox noise significantly. The oil helps to eliminate the noise that comes from shifting gears.
The tranny oil is known as “shockproof” because it substantially reduces the noise. The fact that it offers thick oil films between the gear teeth reduces friction and eliminates the noise during the shifting of gears.
Smooth-shifting of gears
In sports bikes, shifting gears is crucial as it affects acceleration, which would mean the difference between winning and losing.
Therefore, the Red Line 42804 V-Twin oil comes in handy as it makes gear shifting effortless.
High viscosity
Red Line 42804 V-Twin oil has viscosity characteristics that offer a firm thickness that provides a layer of protection over the gear teeth. As such, it greatly protects the teeth from wear and tear by reducing the friction while shifting.
Highly efficient
Efficiency is when you can cover more miles without having to change the oil. With Red Line Big Twin transmission synthetic oil, you do not only go for a prolonged period before changing the oil, but it also maintains your engine during that extended period.
The fact that the oil circulates in the engine also helps to keep it clean. As it circulates, it collects all the debris and dirt that can damage your motor if they clump up.
Reduces temperatures
High temperatures in the engine can lead to overheating, which not only reduces the performance of your ride but also reduces its life. Overheating is especially detrimental to a sports bike.
Red Line V-Twin synthetic oil works to reduce the temperatures, thereby preventing overheating and increasing its performance.
Does not void your warranty
You should use synthetic oil with confidence as it does not affect your motorcycles warranty.
Pink color
One aspect that makes Red Line 42804 V-Twin transmission oil stand out is its pink color. As much as some people may have an issue with the choice of color, it comes in handy. If there is any leakage, it will be easy for you to notice.
Cons
Sensitive riders can sense a smell of the burning oil which can be irritating
A Little More Info
The Red Line 42804 V-Twin transmission oil is especially engineered for use in four-stroke motocross and ATVS. It’s known to be ‘shockproof’ because of how well and effectively it dampens tranny noise.
It is a pink gear oil formulated with high levels of anti-wear chemistry like zinc and phosphorus friction modifiers. They protect gear teeth and in the process, reduce tooth wear. It also dramatically reduces heat to help provide for a thicker film of oil between gear teeth.
This is a 90W gear oil, and is not so ‘heavy’ in structure. This is because the oil clings well with metals that dampen noise so well while preventing wear and tear.
In fact, most users agree that continual use of this tranny oil helps eliminate the shifting ‘clunk’ commonly found in gearboxes. Users notice and enjoy the smoother shifting of gears and notice a great improvement in their bike’s performance with regular use of Red Line’s ‘Shockproof’ tranny oil.
3. Spectro R HDPG6 Heavy Duty Platinum Synthetic 6spd Trans Lube
- Cures noisy six speed transmissions
What we like
- Ideal for long-distance riders as it still performs under high temperatures and load.
- The oil helps to clean your engine as it circulates and collects the dirt and debris
- The G4 technology and other special additives protect your gear and bearing against wear and tear.
- Smooth and silent shifting of gears and reduced whining of the 5th gear
What we do not like
- It is not multifunctional which means you may incur additional costs of buying oil for other parts.
- Spectro R HDPG6 heavy duty oil is costly
Pros
G4 Technology
Spectro R HDPG6 trans oil features a G4 technology and other additives. As such, it offers protection against gear and bearing wear and tear.
The oil also offers more film strength between gear teeth, which reduces drag over the gear. Thus, you will not only have a quieter transmission, but you will also ensure that your gear will last for long.
Smooth-shifting
As mentioned earlier, the 6-speed trans proves to be excellent with power and efficiency. However, it can be a little bit noisier.
Experienced riders can also notice an irritating whining in the 5th gear.
The use of Spectro R HDPG6 tranny oil reduces the noise significantly and a reduction in the whining of the 5th gear.
If the shifting clunk found can irritate you, Spectro oil is your oil of choice as it eliminates it.
All-weather performance
Some bikes will have a problem shifting gears when it is cold. Others will have a problem transmitting under extreme temperatures.
When you use Spectro synthetic oil, your bike is sure to perform under all kinds of weather.
If you do long-distance riding, Spectro R HDPG6 comes in handy as it performs great even when your engine heats up, and it performs even with heavy loads.
Increased efficiency
While standard oils require to be changed after a few miles, Spectro synthetic oil takes you for thousands of miles before you can change it.
Additionally, as the oil circulates in the engine, it collects most of the dirt and debris. Thus, it ensures it’s always clean.
However, it should be best practice for you to check the oil dipstick regularly to determine how clean your engine is.
Warranty
Spectro R HDPG6 oil meets the warranty of Harley Davidsons. As such, you should not have a problem using it on your bike to improve its performance and efficiency.
Cons
It is a little challenging to find it in retail and it is also a bit expensive though it is worth the cost.
A Little More Info
The Spectro Synthetic Trans Lube was specially formulated for use in Harley bikes, especially for the owners who were unhappy with their great, but noisy 6 speed tranny.
Its proprietary oil formula uses G4 Technology and special additives which together help provide for additional anti-wear protection. The oil also helps reduce drag and gear noise, prolongs gear life and also creates a higher film strength in between gears. This SAE 75w140 formulation even helps ease the shifting of gears when cold.
Regular users notice smoother shifting of gears and a remarkably reduction in 5th gear whining. The transmission fluid also helps eliminate the shifting clunk found in most bikes.
Spectro’s technology makes it the perfect oil on long drives and heavy use because the oil does not get affected by heavy loads and extreme heat. The oil is famous, and known for exceeding the warranty requirements.
Conclusion
It is left to you to choose the right transmission oil for your Harley Davidson based on its budget and availability. Whichever trans oil you finally choose to use on your bike make user you change the oil on time.
The first oil change is generally suggested after 500 miles and consequent oil changes after every 2500 miles. It is even suggested to change the oil filter while changing the oil.
No matter which oil you use, and how good the oil may be, it will not work at reducing heat and wear and tear in the gear box if it is not changed regularly. Once again, it is always better to check with your manual to ensure the oil you choose is suitable for your bike.
FAQs
How many quartz does a Harley Davidson transmission take?
The amount of trans fluid you use on your bike depends on the fluid you select. For instance, there are fluids that you can use in the engine, tranny, and the chain case. As such, 1 quartz for the transmission is enough.
How much is transmission fluid for a Harley Davidson?
How much it will cost you to get transmission fluid will depend on the type of tranny fluid you choose. If you go for the conventional fluid, it will be cheaper to buy. Yet, you will not get optimal protection for your tranny.
Harley Davidson is a hardworking bike. As such, the tranny operates under a lot of pressure and high temperatures. If you use conventional trans fluid, it will break down fast. So, you will incur more maintenance costs and shorter drain intervals.
Alternatively, you can choose to use synthetic trans fluid, synthetic trans fluids cost you more than conventional ones.
The high cost is due to the research and method used in their production. Although they cost more upfront, synthetic transmission fluids are cost-effective. They come with specific additives that meet the needs of your engine.
Thus, you will have a cleaner and healthier engine with the best protection. It also does not break down fast. This means you will have fewer trips to the maintenance shop, which saves you a lot of maintenance costs.
The cost of synthetic oil depends on the brand you choose. For instance, Spectro Oil R.HDPG6 1 quart will cost you about $26.78 plus other shipping fees. Red Line Big Twin transmission oil comes at about $35.99. Amsoil VTWIN full synthetic oil 4 Quartz will cost you about $40.00.
How often should I change the tranny oil in my Harley?
According to the manufacturer’s service manual, you should change the engine oil at 5,000 miles. Primary oil should change at 10,000 miles, and trans fluid at 20,000 miles.
A transmission oil change should happen every year. The best idea should be to change the trans oil when it is warm. When it is warm, it is easier to get rid of all the contaminants and debris.
The frequency of oil change may depend on other factors such as hard riding, distance covered, and so on. For a hardworking tranny, it needs a frequent oil change to guarantee protection.
If you ride for extended distances, your oil change interval may be more frequent.
What kind of fluid goes in a Harley tranny?
Harley Davidson should certify the transmission fluid you use on your tranny. As such, you won’t risk voiding your warranty in case of anything.
The transmission oil should withstand extreme temperatures and pressure and heavy loading.
For instance, you can use Red Line 42804 V-Twin transmission oil. The trans fluid ensures that you have a smooth shifting of gears. It also cools down your tranny and reduces the gear noise. It also has a prolonged drain period, which makes it cost-effective.
Is synthetic oil better than standard oil?
Synthetic oil is better than standard oil for some reasons. First, if you use synthetic oil, you will reduce the intervals of visiting your garage for an oil change. While standard oil requires you to change after a few miles, synthetic oil will require you to change after thousands of miles.
Secondly, synthetic oils significantly reduce the noise produced during transmission. Synthetic oil features a viscosity that lubricates the gear teeth and bearing reducing friction and noise.
Additionally, synthetic oil can perform in extreme weather conditions. For instance, some bikes may have a problem shifting gear in extremely cold conditions. However, synthetic oil makes gear shifting smooth under cold and extreme temperature conditions.
Some synthetic oil will also reduce the temperatures of the engine, which prevents overheating and ensures optimal performance.
Are there times that I should not use synthetic oil?
You can use your synthetic oil at any time you want, whether with a new or old engine. The oil promises optimal performance irrespective of the age of the engine.
However, synthetic oil is highly slippery. For a new engine, some parts need to mate so that they can work efficiently. Synthetic oils may, therefore, hinder the mating.
Is synthetic oil multifunctional?
Some dealers may tell you that a single oil product will take care of all your lubrication needs.
However, that is not the case. To get the best performance, you should have synthetic oil for your gear, synthetic oil for the clutch, chain and synthetic oil for your engine.
Synthetic oil for your gear protects your gear and bearing against wear and tear and also aids in the smooth shifting of the gears. The lubrication of gear teeth also significantly reduces noise while shifting gear.
Synthetic oil for your engine ensures that it is healthy and clean at all times. As the oil is circulating in the engine and providing the necessary lubrication, it also comes across dirt and debris from various parts. The oil absorbs the dirt and prevents it from clumping up, which would affect its performance.
Does the use of synthetic oil void my warranty?
Most synthetic oils do not void your warranty. They meet and exceed the requirements of various motorcycle brands for a warranty to stand.
Which is the best synthetic oil for me to choose?
There are tons of synthetic oils in the market for you to choose from.
In this article, we have provided you with the best three types of synthetic oil, according to our research. These include Red Line 42804 V-Twin transmission oil, which is especially useful for sports bikes and four-stroke motocross.
Also, we have Spectro R HDPG6 heavy duty synthetic oil, which works with six-speed tranny. Six-speed is famous for its high performance. However, it can be noisy. The synthetic oil, therefore, makes it effortless to shift through the gears, eliminates the noise, and also reduces the whining of the 5th gear.
Finally, we have the Amsoil MYTQT-EA V-Twin transmission fluid. The synthetic oil protects the gear, chain, and bearings from wear and tear. It also aids in smooth shifting and reduction of noise.
Last update on 2023-09-22 / Affiliate links / Images from Amazon Product Advertising API
