A vehicle’s transmission system transfers power from the engine to the drive shaft and differential, allowing the wheels to turn. Like the engine, the transmission needs to be at a specific temperature range to perform its best.
170 to 225 degrees Fahrenheit is the normal transmission temp for most vehicles. However, the transmission temperature can go as high as 240 degrees Fahrenheit if pushed to its limit.
The torque converter is where the heat is created in an automatic transmission. Heavy loads can overheat the fluid and change its properties so that it deposits sticky varnish on the valves, which can cause shifting problems. A vehicle that pulls heavy trailers or hauls a lot of weight regularly should have more frequent transmission fluid changes than vehicles that don’t pull heavy loads.
Furthermore, because the torque converter generates heat (shearing the fluid), just sitting in traffic or at a drive-through on a hot day with the transmission in drive can cause the transmission to overheat to the point that it pushes fluid out the transmission’s vent port. If you’re going to be sitting for a long time in traffic or anywhere else, slip the gear selector into park or neutral to prevent transmission overheating.
A vehicle that pulls heavy trailers or hauls a lot of weight regularly should have more frequent transmission fluid changes than vehicles that don’t pull heavy loads.
– Richard McCuistian, ASE Certified Master Automobile Technician
Prolonged high temperatures in the transmission can cause severe issues, sometimes leading to transmission failure. If your transmission’s temperature is more than 225 degrees Fahrenheit, something might be wrong with your vehicle.
The torque converter can generate high heat, especially when the vehicle is carrying a heavy load and the torque converter clutch is disengaged. That’s why vehicles come equipped with an automatic transmission fluid (ATF) cooler.
The cooler is a part of the engine cooling system’s radiator that helps reduce the temp of the coolant, which absorbs the heat from the ATF.
Towing trucks usually come equipped with a larger cooler or a series of liquid-to-liquid or liquid-to-air coolers to manage heat during towing.
Note that severe heat in your transmission can be detrimental, but so is extreme cold. That’s why some vehicles also have an ATF heater, so the fluid can be warmed when it’s cold. Warm fluid can lubricate metal parts better.
Transmission overheating happens when the cooler can’t keep your transmission temperature within the recommended range. Here are some of the issues that can heat your transmission.
The condition of your transmission fluid affects how your transmission works.
Low fluid levels, for example, can cause less lubrication, damaging your transmission components in the long run. Inadequate transmission fluid can also cause low hydraulic pressure, resulting in slipping, hard shifting, and overheating.
If you’re not sure how to check your transmission fluid level, you can check out our guide.
The transmission usually has a solenoid that regulates the flow of transmission fluid. If the solenoid fails, the system will not have enough transmission fluid.
Replacing the solenoid will usually solve the issue.
Extreme heat can affect your transmission’s temperature. For example, hot summer days can raise the transmission fluid’s temperature, making it easier for it to overheat.
How you drive your vehicle affects your vehicle’s transmission.
Constantly speeding up and slowing down can take its toll on your transmission and increase its temperature. Frequently shifting gears can also have a similar effect.
So if you often drive through busy streets with heavy traffic, watch out for transmission overheating.
Your transmission works harder than usual when you tow heavy loads. So if you’re using your ride as a workhorse, watch for signs of overheating.
Here are the symptoms you should watch for that can indicate it’s time to ask a mechanic to inspect your transmission:
If your vehicle has a transmission warning light, it will illuminate once the system detects an issue in your transmission. This light looks like a gear with an exclamation point at the center.
Don’t ignore any weird odor coming from your car. If you smell something burning when you’re driving or parked, have a mechanic check your vehicle.
Many issues can cause a burning smell, and one of them is an overheating transmission. The source of the burnt smell can be the burning transmission fluid inside.
If your engine doesn’t respond as quickly as usual, it might be due to an overheating transmission. Overheating can cause faults in the transmission, causing it to exhibit issues while driving.
If your engine is overheating, your transmission could be in the same boat. To be safe, make sure to have your transmission inspected too.
Experts don’t recommend driving your vehicle while its transmission is overheating because you would only damage it more.
Instead, drive your vehicle to the safest side of the road and wait for your transmission to cool down. Contact a towing service to take your ride to the nearest repair shop.
However, if towing isn’t possible, wait for the temp to drop and maintain a slow speed until you reach the shop.
It takes work to fix transmission-related issues, which is why keeping your transmission in optimal condition is vital. That includes making sure the system’s temperature is within the recommended range.
Here are some tips to help you avoid transmission overheat:
Buy an aftermarket cooler if you can’t avoid towing or carrying heavy cargo loads to manage the heat in your transmission more effectively.
Consult your mechanic if you need help determining whether buying an aftermarket transmission cooler suits your vehicle.
Check your transmission fluid at least once a month. Book a transmission service right away once you notice your transmission fluid is in poor condition or if the level is low.
Remember that low fluid levels could indicate a fluid leak, so inspect your ride right away before things worsen.
Most manufacturers recommend checking the transmission every 30,000 to 60,000 miles. However, you’ll have to have your transmission checked more frequently than that if you use your ride for towing.
You can consult your owner’s manual or talk to a trusted mechanic to clarify your transmission maintenance intervals. A standard transmission maintenance service includes changing the transmission fluid, filter, and pan gasket.
If you notice any signs of transmission problems, you should address them as soon as possible. Have your vehicle inspected by a transmission professional, and replace any worn parts immediately.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.