Does Changing Transmission Fluid Help Shifting?

If you own a fleet of cars, are in the automotive industry, or are a heavy equipment operator, chances are you’ve encountered some type of transmission issue such as a shifting problem in one or more of your vehicles. The following question most likely is at the forefront of your mind: does changing transmission fluid help shifting?

Here are some questions to contemplate. Are you noticing any strange noises coming from your transmission when it is shifting? Is the sifting problem so bad that you need to send it to the repair shop for a checkup? Does the transmission need to be rebuilt or replaced? Is the torque converter on its last legs and due for a complete rehaul or replacement? Could the shifting problems simply be a case that requires only a change of fluid or filter?

In most instances, the seed of these issues in most cases originates from the quality and type of transmission oil that is being used. This post will present information in how by simply changing your transmission fluid to a different type and quality could be the answer to your shifting problems.

Is the Quality of Your Fluid Causing Transmission Issues?

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If you’re a professional fleet owner or just a consumer, there are a multitude of choices to make when deciding the type of transmission fluid and the quality of transmission fluid to run in your vehicle or fleet. First, we’ll discuss a common multi-vehicle automatic transmission fluid / ATF fluid.

When a lubricant manufacturer creates a formulation for a transmission fluid, they typically have a price point in mind and the performance parameters that must be met to reach that price point. A large percentage of lubricant manufacturers are engineering ATF fluids to come in to the market at the lowest possible price while still meeting the minimum OEM specifications. Most conventional regular automatic transmission fluids will start out using mineral or petroleum base stock oils. A base stock oil determines the foundation or architectural structure of that oil and how it will ultimately perform.

AMSOIL Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid.
AMSOIL Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid

When trying to keep the selling price of such a fluid low, the only real choice in base stocks would be mineral based or petroleum based. Using conventional mineral base stock oils will deliver an ATF fluid that is useful only in light duty applications. If a fleet owner or heavy equipment operator decides to use a mineral or petroleum based product with a low price, this type of transmission fluid could compromise performance if it is asked to perform in heavy duty or extreme environments.

Conventional petroleum base stock oils have an inherently natural limiting factor. The limiting factor lies in its molecular structure. The molecules of a mineral base stock oil are of different sizes and uneven. Translated, this means that when the fluid flows, it creates unwanted fluid friction because of these different sized molecules. When in operation, this fluid friction creates unnecessary heat. When you add the fluid friction along with friction being caused by the moving parts inside the transmission, together temperatures start to rise quickly within the transmission.

The higher than normal temperature found in a transmission running mineral based automatic transmission fluids will caused fluid degradation. Mineral based oils have only average thermal stability. They are unable to withstand high temperatures for long periods of time. When an oil is susceptible to heat, it oxidizes. When an oil oxidizes, deposits such as varnish, sludge, and carbon can begin to accumulate.

This slow accumulation of contaminants and deposits can and will begin to negatively affect transmission shifting. Unfortunately, transmission fluid is not changed as often as motor oil is. When a conventional ATF fluid is left unchanged in a transmission, problems can multiply and spiral out of control. Ultimately, catastrophic failure could occur. A fresh mineral based transmission fluid quickly turns into an old degraded fluid, causing unnecessary wear and tear.

The bottom line is a mineral based ATF fluid is not made for long service life or for heavy duty extreme operating conditions.

AMSOIL Signature Series Multi-Vehicle Synthetic Automatic Transmission Fluid.
AMSOIL Signature Series Multi-Vehicle Synthetic Automatic Transmission Fluid

In addition to the uneven molecular structure of a mineral based oil, these base stock oils come with byproducts that unfortunately are unwanted and not useful. One of the byproducts that offers no useful function is wax. This wax causes the fluid to thicken when temperatures drop during the winter. Mineral based oils tend to thicken when temperatures become cold. This thickened oil finds it difficult to flow through the many small and tight oil galleys found within a transmission.

Since mineral oils create unwanted fluid friction, plus the addition now of wax induced oil thickening when temperatures are cold, one can understand better why transmissions tend to have shifting issues when they are cold or when the ambient temperatures are cold.

It’s basic human nature to shop for the lowest priced lubricant such as an automatic transmission fluid. At the end of the day, the lowest priced fluid seems to always be a mineral based fluid and the choice becomes easier when the technical data sheet says it meets OEM specifications. But as we’ve alluded to already, is a low priced mineral based transmission fluid your best choice over a long period of time? If in fact what we’ve discussed already comes true, then such a low priced fluid could become quite costly.

If the fluid has to be replaced quite often because it no longer meets OEM specifications, what happens if you notice that you are making more trips to the repair shop than expected? At this point it might be a good idea to reassess how cost effective that low priced ATF fluid really is.

Studies have shown that the cost of downtime and the cost of replacing parts can be quite expensive. If this scenario is the direct result of using a cheap transmission fluid, then that becomes an issue of stepping over dollars to pick up dimes. A better strategy might be to consider a high performance automatic transmission fluid that is engineered specifically for extreme duty applications and that offers proven long service life.

AMSOIL 100% Synthetic DCT Fluid.
AMSOIL 100% Synthetic DCT Fluid

Sometimes a different perspective in looking at lubricants is all that is needed to solve seemingly complex problems. If you continue to ask yourself the question, does changing transmission fluid help shifting, while the answer seems to be yes, consider moving away from using low priced transmission fluids and consider trying a high performance synthetic transmission fluid. Let’s take a look at how synthetics can solve problems and save you money in the long run.

Are Synthetics a Better Choice?

We’ve looked at mineral based oils, now let’s see why a lubricant chemist might decide to formulate with pure synthetic base stock oils. If the philosophy of the lubricant manufacturer is to produce a high performance synthetic transmission fluid, the only choice would be to start out with 100% pure synthetic base stock oils. Immediately, choosing a synthetic base stock oil over a mineral base oil will deliver huge benefits. Why? Well, first of all, 100% pure synthetics are man-made. The goal was to create a base oil with the perfect molecular structure. That perfect structure means the same sized molecules all evenly created.

Because of these same sized molecules, a synthetic base oil flows without fluid friction. From the get go, this oil is not creating unwanted heat like a conventional oil does, due to its unwanted fluid friction.

AMSOIL Synthetic CVT Fluid.
AMSOIL Synthetic CVT Fluid

Another huge advantage that man made synthetic base oils offer is that they have no wax or other useless byproducts. The next benefit of synthetic base stock oils lies in their very high viscosity index number. Synthetic base oils naturally come with a higher VI number when compared to mineral based oils. Having a high viscosity index number means the lubricant will keep its viscosity and not change when exposed to a broad range of temperatures.

For example, a 5W20 transmission oil will keep this same viscosity no matter the temperature it encounters. Hot or cold, it stays in grade. In comparison, a 5W20 mineral based transmission fluid will thin out when exposed to elevated temperatures and start to thicken when temperatures drop.

A 100% pure synthetic automatic transmission fluid will preserve the shift quality designed for your vehicle due to the characteristics of synthetic base stock oils. A transmission fluid that is formulated with man made 100% synthetic base stock oils will be compatible with seals, gaskets, and the many components found in a broad variety of automatic transmissions. Synthetic base stock oils are made to provide extended service life and are extremely durable.

So, while you’re asking the question does changing transmission fluid help shifting, we’ve already seen how switching to synthetic base stocks can deliver an answer of yes for this question.

Next, let’s discuss how a top tier high performance additive package blended into synthetic base stock oils can make a transmission shift effortlessly.

How to Make Your Transmission Last

The next step in formulating a high performance synthetic transmission fluid that will provide the proper shifting patterns is to engineer in specialized additives.

Mineral based ATF fluids, as we’ve already discussed, are made to meet a price point rather than outright performance. When blending a light duty ATF fluid, only the bare minimum volume of additives are required to meet the basic minimum OEM specs. This philosophical approach deals with more economics instead of delivering real benefits and performance. The primary parameter is to make an oil that can pass basic industry standard requirements and no more than that.

The sad fact is, these low end fluids do find their way into many commercial fleets and heavy equipment operations. The reality should be that mechanics for such heavy equipment operations and fleet operations need to take a serious look elsewhere if downtime is to be reduced and maintenance costs decreased. There simply is too much at stake and too much money invested in equipment to expect conventional transmission fluids to protect critical transmission parts.

Once the equipment is in the field, with such fluids, the troubles begin. These low performing lubricants will slowly cause slipping. This slipping causes more shifting problems, and suddenly, the warning signs become more and more frequent. Out of sight, out of mind, when considering what is really going on inside an automatic transmission, soon becomes a very clear visionary reality.

A specialty lubricant manufacturer takes an entirely different view in how lubricants should be considered for heavy equipment, fleet owners, and even consumer vehicles. In all three instances, a custom blended manufacturer looks at any piece of machinery as a major investment, whether it’s one car per family, 100 vehicles for a fleet, or a multi vehicle heavy equipment operation. This equipment needs and should be protected with the best possible lubricants.

AMSOIL Synthetic Powershift Transmission Fluid SAE 30.
AMSOIL Synthetic Powershift Transmission Fluid SAE 30

They take the view that a high quality oil is far less costly than parts and service costs. When it comes time to design an additive package for a transmission fluid, only the best is considered. The ultimate goal is to far exceed industry standards. Not by a little, but by a lot.

An added insurance policy is formulated into the chemistry so that there is peace of mind when an oil is expected to deliver protection under extreme conditions. To get this type of performance, a chemist will first make sure that the chemistry is balanced and then they will increase the volume of additives to further improve and enhance performance and longevity.

Generally speaking, additives are there to combat foam, oxidation, rust, corrosion, wear, leakage, and cold temperatures. The intent is to create a lubricant that can combat and deal with the most basic issues and to create a shield of armor around the components inside the transmission so they are protected from the barrage of conditions and elements occurring inside the transmission when in operation.

Typically, automatic transmission fluids are viewed differently than motor oils. They are not changed as frequently as engine oils. Unfortunately, if conventional or mineral based fluids are being used, that is a risky strategy. The fact is, mineral based ATF fluids use lower grade base oils and only the bare minimum of additives. The complete opposite is the case with high performance synthetic ATF fluids. They use superior synthetic base stocks and robust amounts of top tier additives.

Transmissions that utilize these superior fluids derive many benefits and are provided exceptional protection. Without a doubt, these oils are durable enough to last for long durations of service and in many cases, transmission life is actually doubled and service drain intervals of the lubricant tripled. The same cannot be stated for mineral based ATF fluids.

To maintain cleanliness within the transmission and to provide the necessary film of lubricants to minimize wear of components, matching synthetic base oils to heavy duty additives is the ticket. A high tech automatic transmission fluid offers long drain intervals, withstands tremendous heat, and is extremely thermally stable, which translates to little or no oil consumption.

By conducting oil analysis on a high performance synthetic ATF fluid, the superiority of such an oil will be seen in the results. These results will say that the oil is still in new condition after long term use and an oil change almost becomes a thing of the past. A quality synthetic multi purpose vehicle transmission fluid will provide many benefits with the right synthetic base oils and additive chemistry.

How to Protect Shift Quality

To keep shift quality and shift times factory new, specialized friction modifiers are utilized. It is critical that these specialized additives are blended in in a balanced fashion and with the proper amounts so that the fluid remains tough enough to deliver quality shifts as designed by the OEM over a long service life.

Regardless of how many miles have been driven, the transmission fluid must be able to deliver acceptable and smooth shifts. For school buses, transit buses, emergency vehicles, and other similar fleet vehicles, a heavy duty synthetic automatic transmission fluid must provide strong anti-shutter performance. It is a given that a properly engineered synthetic ATF fluid provide and maintains proper shifting. Plus, this fluid needs to flow freely when temperatures are extremely cold, it must stay in grade and not shear down, and it must be able to provide faultless performance in the most extreme operating environments.

AMSOIL Torque-Drive® Synthetic Automatic Transmission Fluid.
AMSOIL Torque-Drive® Synthetic Automatic Transmission Fluid

The two main culprits that cause shifting problems are sludge and varnish. The only way to combat and limit the formation of varnish and sludge is to source a high performance ATF fluid. The choice is clear. Only 100% pure synthetic base stock oils, coupled with the finest additive chemistry will be strong enough to withstand thermal degradation and be resistant to oxidation. This type of fluid will keep transmissions free of harmful varnish and sludge.

If you’re a fleet owner, a heavy equipment operator, or simply own one automobile and your automatic transmission fluid currently uses a mineral based ATF oil, then based on the information provide so far, it makes sense to switch to synthetics.

To gain the most benefits from the switch, the vehicle will likely require a transmission flush. After the flush, the transmission can now be filled with a 100% pure synthetic ATF fluid. The result should reduce or eliminate any shifting issues you’ve been having.

Does changing transmission fluid help shifting? If you’ve been experiencing inconsistent shifting caused by deposits such as varnish and sludge, then the answer is yes. If the shifting problems are due to viscosity breakdown, foaming, cold weather thickening, then switching to a quality synthetic ATF fluid will without a doubt make the answer a resounding yes.

Switching to Synthetic Gear Oils to Fix Shifting Issues

If you’re encountering shifting problems in a manual transmission, the problem could be a simple one, such as using the wrong lubricant. Is the current gear oil you’re using tough enough to deal with extreme pressure, tremendous heat, or cold temperatures? Like any quality lubricant, gear oils included, the types of base stock oils used to formulate the product is critical to how it performs. We’ve already discussed the many limitations found in low priced mineral based lubricants and the same applies to mineral based gear oils.

AMSOIL Manual Transmission & Transaxle Gear Lube 75W-90.
AMSOIL Manual Transmission & Transaxle Gear Lube 75W-90

If real solutions are to occur, then it is imperative to concentrate your research into whether pure synthetic gear oils will help. A pure synthetic gear oil will deliver an oil that is free of fluid friction and free of unnecessary byproducts and impurities. If shifting problems are occurring because of deposits such as varnish or sludge forming within the gear box, then switching to a synthetic base oil will help get rid of that issue.

It goes without saying that most heavy equipment operators, fleet owners, and even consumers with a single vehicle hope for maximum protection and performance from their vehicles. With that goal in mind, let’s agree based on what’s been written so far in this blog post that only the highest quality oils should and need be considered to gain maximum protection and performance.

By choosing a pure synthetic gear oil, manual transmissions and final drives will benefit greatly.

How to Lower Heat in Your Transmission

A vast majority of manual transmissions are asked to perform in extremely high temperature environments. Temperatures can range from 280 degrees F up to 320 degrees F. These high temperatures can cause transmission synchronizer coking. Transmission synchronizer coking is a symptom that indicates a difficulty in gear shifting or gear changing. When temperatures are high enough to cause transmission synchronizer coking, then it most likely means that the gear oil being used is of low quality and lacks durability to withstand high temperatures.

Conventional mineral based gear oils lack the kind of thermal stability to deal with high heat and thus the oil oxidizes, breaks down, and eventually causes these coking issues. When this happens, it becomes quite difficult to drive the vehicle because the transition from the clutch causes an inefficient transfer of power from the engine to the drive chain system.

AMSOIL Manual Synchromesh Transmission Fluid 5W-30.
AMSOIL Manual Synchromesh Transmission Fluid 5W-30

A simple solution to eliminate transmission synchronizer coking would be to choose a high performance pure synthetic gear lubricant. AMSOIL offers a variety of heavy duty pure synthetic gear oils that will eliminate these types of shifting issues. A pure synthetic gear oil flows easily and without fluid friction, quickly reaching gears and bearings. A synthetic gear oil will eliminate any deposit formations caused through the use of inferior mineral based oils. The end result is a fast flowing lubricant that quickly reaches passageways and filters. By eliminating unwanted deposits and contaminants, shifting issues are reduced or eliminated.

Finally, let’s finally answer the question of does changing transmission fluids help shifting? The answer now seems perfectly clear. Switching from low cost mineral based fluid to 100% pure synthetic based transmission fluids will deliver many benefits. The best value transmission fluid is the one that solves problems, minimizes downtime, enhances performance, and saves money. The only way to get these kinds of benefits and to protect the large investment you’ve made in your vehicle or equipment is to choose and use the absolute finest possible lubricants.

At the end of the day, investing in the best synthetic transmission fluid is a lot cheaper than your equipment breaking down on the job due to a transmission failure. The cost of a quality oil is far less than the cost of lost profits and huge labor costs and parts expenditures.

Note: before switching lubricants, always refer to the vehicle’s owners manual for the proper viscosity and lubricant specification.