Do You Check Transmission Fluid When Hot or Cold?

Are you driving your car while the transmission fluid (view on Amazon) is low? Do you know whether your transmission fluid level is low? Transmission fluid is another must have for a vehicle with great performance. This article will show you how to identify a low transmission fluid problem in your vehicle and steps you can take to correct the problem.

Why Cars Need Transmission Fluid

Of all the fluids that run through your vehicle’s system, the transmission fluid is by far of the most important. Typically, the transmission fluid is red; however, it may be other colors. Whether your vehicle has an automatic or manual transmission, keeping the transmission fluid topped off will help you to avoid some serious issues that could permanently damage your car.

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Manual Transmission Fluid

Manual transmissions are the traditional design. For a long time, the manual transmission was the only option. Manual transmissions only use transmission fluid to lubricate different parts. When the fluid is low, metal-on-metal grinding occurs and wear down. Manuals are somewhat less susceptible to things going wrong because of the transmission fluid. Manual transmissions use gear oil to help do the job. Yet, the manual transmission can overheat when there is not enough fluid. The clutch and gears are primary areas that are affected by low transmission fluid in the early stages.

Automatic Transmission Fluid

The automatic transmission may be a bit more sophisticated; however, it also can experience serious issues when the transmission fluid runs low. Transmission fluid keeps the transmission lubricated and cool. The fluid absorbs some of the heat and transfers it to the radiator. As a hydraulic fluid, transmission fluid also facilitates gear shifting. The torque converter needs transmission fluid to form hydraulic circuits to transfer rotational force between the transmission and the engine. Transmission fluid decreases instances of slippage. Something else that is important, the transmission fluid facilitates the transfer of power to your engine.

Causes of Low Transmission Fluid

The transmission system differs in cars that automatic or manual. The automatic requires automatic transmission fluid (ATF), while the manual still use the plain stuff. Other than that, either model may experience low transmission problems for different reasons. Here is a list of the most common things that can cause transmission fluid levels to drop:

Time – Generally, transmission fluid does not have to be changed or replaced like oil. It’s built to last for a while. Yet, transmission fluid deteriorates in some cases and can even become contaminated over time as parts of the transmission wear down. When the fluid deteriorates, it becomes a darker red and may give off an odor.

Heavy wear and tear – Even the sturdiest of vehicles can only take so much. If you drive your vehicle often in stop and go traffic, or on rough terrain where you have to keep shifting gears, the operating temperature rises more than normal, straining the transmission fluid and the transmission. When this happens, it’s common that other things are also wearing down on your vehicle. The CEL light may be on for more than one reason.

Heavy hauling or towing – If you do a lot of heaving towing and hauling, the transmission’s life cycle decreases at a faster rate. The extra work means the transmission has to work harder. After making several hauls or towing of heavy stuff and your system has been hard like that for a long time, you can assume that some of the fluid may have dissipated.

You don’t care about your car – Regular inspections or maintenance should include checking your oil and transmission fluid as a form of preventive maintenance. If you don’t have your vehicle serviced regularly, these fluid problems can develop and build up over time. If your transmission fails because of a lack of maintenance, it’s going to cost a lot to repair at the auto workshop.

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Gasket failure – Gaskets play a very important role in different parts of the vehicle. A common cause of transmission fluid leaks in manual transmissions is gasket failure or leaks. The gasket makes a seal between the engine, gearbox, and output shafts. The gaskets also wear down from pressure, friction and the resulting heat which cause the transmission fluid to leak. The gasket problem intensifies over time.

Line and connection leaks – Some transmissions have lines that carry the fluid to the transmission oil cooler. The line system may have a leak or the clamps may be worn. The fluid leaks and decreases then amount of transmission fluid on reserve.

Symptoms of Low Transmission Fluid

Fluids are the lifeline of any vehicles. Several things commonly happen when your vehicle is low on transmission fluid. Whether your car is an automatic and manual, transmission fluid is an integral part of your vehicle running smoothly. Check out these signs that probably mean your vehicle is low on transmission fluid:

Warning light on the dash/Limp Mode – When your transmission fluid is low, the engine control module (ECM) (view on Amazon) or transmission control unit in some vehicles will activate a Check Engine Light (CEL) warning on the dash to let you know you’ve got trouble.

Transmission fluid leaking – Common transmission fluid leaks occur in the gasket between the transmission and the transmission fluid sump and You may see transmission fluid on the ground, under your vehicle. If the fluid is leaking, you can be sure that there is not enough fluid in the vehicle for proper functioning. The more the fluid leaks, the more damage to your car. It can be difficult to spot the leak in the early stages.

Gear slipping – When you change gears and your vehicle falls back, this is called transmission slipping. The synchronization between the engine and the rest of the system causes a slip. Spikes in the RPMs, sudden shifting up or down, and grinding noises are all a part of transmission slipping, which could cause overheating. When you shift gears, you can hear grinding noises as the transmission struggles during the gear shift.

Irregular shifts – Shifting gears is what enables your vehicle to increase and decrease speed; and to go from forward to neutral or reverse. When a vehicle shifts irregularly, the gear changes are delayed, slamming, or accelerated. Low manual transmission fluid symptoms is a common problem in automatic transmissions.

Unable to change gears – If your vehicle has no transmission fluid in it at all, you will not be able to change gears. Or, you may hear a scrubbing noise as you try to move from one gear to the next. When this happens, your vehicle is beyond the beginning stages of a transmission fluid or transmission problem.

Delayed gear engagement – Pauses in shift for drive and reverse happens for a few seconds. The gear change does not have enough pressure to make the shift. The gears may just be totally unresponsive. Vehicles with a manual transmission may operate a bit longer without sufficient transmission fluid; however, the manual transmission eventually starts to malfunction.

Overheating transmission – Once you start driving, it does not take long at all for the transmission fluid to heat up. The transmission fluid temperature should never exceed 175 degrees. Every 20 degrees higher reduces the life of the transmission fluid by 50%. Many things happen when the transmission overheats. When transmission fluid is lacking, friction occurs that creates heat. Seals may harden, varnish appears on metal parts, and clutches may slip. Smoke may come from under the hood, you may lose power, a burning smell comes from under the hood, or while driving the gear shifts erratically. This is one of the last phases before the transmission fails.

Transmission failure – The correct amount of transmission fluid assures that there is a correct amount of pressure to able to change gears. If your vehicle will not shift gears, and after adding transmission fluid, it still will not change gears, the transmission has failed.

Solutions to Low Transmission Fluid

Driving with low transmission fluid can be dangerous as your vehicle may start to behave erratically or your transmission may fail. Here are a few things you can do to avoid trouble because of low transmission fluid:

Check your owner’s manual – Your owner’s manual is a way for you to get acquainted with your car. The information it gives will be specifically for your vehicle.

Check the transmission fluid levels – Normally, you should not have to refill your transmission fluid. Yet, if your fluid is low, it’s best to add some until you can get it to a repair shop. If your car has a dipstick for the transmission fluid, simply pop the hood and check the transmission fluids yourself. Start the engine and let it idle until the transmission reaches 40C. Check the transmission dipstick while the car is idling. If the mark is below the MIN dash, add some transmission fluid and check with the dipstick again.

Use an OBD2 Scanner – If your car does not have a dipstick, or you don’t know how to access it, use an OBD2 Scanner (view on Amazon) to pinpoint the problem. There are several codes that are associated with the transmission fluid. The P0868 trouble code will show when the transmission fluid pressure is problematic. The powertrain control module (PCM) detects the problem and send the code. This code is often activated because of a transmission fluid leak. The P2740 trouble code will show with problems associated with the transmission fluid temperature sensor B circuit.

Take the car for inspection – If you suspect you have problems with low transmission fluid, a certified technician or even the dealership can inspect the vehicle. If you are not sure what the problems is, taking it to a garage is your best bet.

Maintain the gearbox – You should make sure that your gearbox is clean and lubricated to reduce wear and tear can help. Make sure the gear teeth are not damaged.

Replace transmission pan gasket –The pan gasket on your car may be leaking, which means it must be replaced. Refer to the owner’s manual for your vehicle type to determine the seal maintenance status. The replacement is a pretty simple job that most mechanically inclined owners can perform. If not, take your vehicle to a certified professional who can get the job done right.

Transmission Overhaul – When the transmission has been severely damage from a lack of fluids and high temperatures, the transmission may have to be overhauled. This means the transmission is disassembled so that any wear or damage can be identified. Any friction surfaces are replaced. This procedure can be expensive depending on the make and year of your vehicle and how long the fluid leaked.

Replace the transmission – Small problems, when left unattended, cause big problems. If you have driven your car with low transmission fluid for a while, or it has been leaking for some time, the outcomes may be irreparable. In this case, it may better to just replace the entire transmission and start over.