No car owner will be able to undermine the importance of automatic transmission fluid. The lubricant can guarantee the car’s smooth operation by helping components avoid friction.
Additionally, automatic transmission fluid conditions seals and gaskets, controls temperature and makes metal surfaces resistant to wear. Given its very important role, it is equally important how much transmission fluid to add.
This article will provide you with all the necessary on automatic transmission fluid, and how much transmission fluid to fill your car with!
What Is Automatic Transmission Fluid?
Automatic transmission fluid, or ATF, is a lubricant that is responsible for smooth shifting, wear-and-tear protection of transmission components, and increased RPMs and manoeuvrability of your vehicle.
Transmission fluid brings many benefits to the table, and so, more and more owners are becoming adamant about ensuring there is always a sufficient amount of fluid in the transmission.
The real question is when do I know when to change transmission fluid and how much transmission fluid should I add?
Here’s an example of some Automatic Transmission Fluid readily available on Amazon:
- Provides consistent shift performance for new and old GM transmissions
Prices pulled from the Amazon Product Advertising API on:
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.
How Do I Know When to Change Transmission Fluid?
Determining the need for changing the automatic transmission fluid is never a matter of guessing. The key is inspecting the fluid levels as this will typically indicate when you would need to top up your vehicle.
Many drivers, however, often tend to neglect regular inspections, which consequently leads to encountering one of the several following known transmission issues:
- Burning smell
- CEL (check engine light) or TTL (transmission temperature light) coming on for no apparent reason
- Consistent jumping of gears or shifting delay
- Disengaged transmission while driving
- Grinding/humming/buzzing or other types of engine noise
- Intermittent surging
- Overheating
- Power loss
- Transmission slippage or engine revving high without shifting
- Visible fluid leak from the engine block
If you encounter any gearing or transmission issues like the ones above then you should immediately examine your transmission fluid levels and the quality. Vehicles with dipsticks allow more convenient checking of fluid levels. Then you must wonder how much transmission fluid should be on the dipstick? We’ll get to that later in the article, don’t worry!
However, if you own a car which doesn’t have a dipstick, you need not to worry, ATF on vehicles with sealed transmissions can be inspected by raising them levelly and accessing their underneath.
Signs That the Automatic Transmission Fluid Needs Changing
When checking, you must make sure that there are no leaks, and that the transmission fluid is pinkish, clear amber or cherry red. You do not want to be seeing a deep red, brown, or milky ATF.
Why? Well, it doesn’t take long for the automatic transmission fluid (ATF) to heat up once the vehicle is in motion. Normal driving will raise fluid temperatures to around 80 degrees Celcius (175 F), which is a normal temperature range at which most ATFs are designed to operate.
However, if the fluid temperature goes a fair bit higher, the life of the fluid will begin to rapidly plummet. And the real problem here is that even if you’re driving along the road normally, it can push fluid temperatures well beyond safe limits. And the trouble will begin once that happens.
When operating temperatures become elevated, the automatic transmission fluid oxidizes, making it turn brown in colour and taking on a smell similar to that of burnt toast.
This elevated heat will then destroy the transmission fluid’s lubricating qualities and friction characteristics. Varnish will then begin to form on internal parts (such as the valve body) and interfere with the operation of the transmission.
If the temperature were to be allowed to rise above 180 degrees Celcius (250 F), rubber seals begin to harden, which ultimately leads to numerous leaks and resulting pressure loss. At higher temperatures, the transmission begins to slip, which will only aggravate the overheating even further.
Eventually, the clutches burn out and the transmission calls it quits. And then what? You’re left with a very hefty bill to get it all fixed. That’s why it’s important to consistently check, and change your transmission fluid when necessary.
How Much Transmission Fluid Do I Need?
If you’ve inspected your ATF level and it confirms insufficient fluid levels, then you should prepare to top up your car warming it up. Do so by starting the car’s engine and letting it run for around five minutes, or until it has warmed up to operating temperature.
After doing so, you should recheck the fluid levels. If they are still lacking, slowly add a quarter to a half quart of transmission fluid at a time. And do this repeatedly until you have reached the sufficient level full on the dipstick.
Tip: You should always check fluid levels at operating temperature.
Inspect the cold and hot marks and make sure the fluid level is in the middle of these two when the engine is warm. It doesn’t matter how empty the transmission is of fluid, it is always best to pour in the transmission fluid little by little to ensure that you don’t overfill it, as this can cause damaging effects.
Consequences of Overfilling
No matter what, one of the most important considerations when you top your car up with transmission fluid, is to never overfill it. There are several important reasons overfilling ATF has been discouraged and these include:
- Difficulty in shifting gear (a symptom of a foamy transmission fluid)
- Insufficient lubrication within the crankshaft results in an overheating engine
- Oil starvation
- Part pitting, failure, or damage due to excess pressure caused by the excessive fluid amounts
- Seal failure leading to a transmission rebuild (very costly)
- Transmission fluid leaks (signs include puddles or drips underneath the transmission)
- Vehicle malfunction
Considering all of the above consequences, you will be far safer by strictly adhering to the manufacturer-recommended transmission fluid quantities which you should be able to find in your owner’s manual or by contacting them directly.
Following their guidelines will prevent the occurrence of any of the above problems and ensure the seamless operation of your vehicle.
How Much Transmission Fluid Do I Need For My Vehicle?
Below is a table which can be used as a rough range of how much transmission fluid to add. It is advised that you check your vehicle’s owner’s manual, however, for the specific transmission fluid capacity of your vehicle.
| Vehicle Type | Volume (Litres) | Volume (US Quarts) |
|---|---|---|
| Convertible | 1.9 – 10 | 2 – 10.6 |
| Coupe | 3.8 – 12.8 | 4 – 13.5 |
| Estate | 0.9 – 9 | 1 – 9.5 |
| Eco car | 1.4 – 3.8 | 1.5 – 4 |
| Family car | 1.7 – 9.7 | 1.9 – 10.3 |
| Hatchback | 1.8 – 8.6 | 1.9 – 9.1 |
| Minivan | 1.9 – 9.2 | 2 – 9.7 |
| Pickup truck | 2 – 11.3 | 2.2 – 12 |
| Sports car | 3.3 – 16.2 | 3.5 – 17.1 |
The size difference between the different car types has a close-to-negligible impact on its transmission fluid requirements. However, the reverse is true if considering other factors.
How much transmission fluid to fill depends on the type of transmission, gearbox version, number of cylinders for fuel intake, the presence of a limited-slip differential, and whether it takes petrol or diesel.
For example, more recent diesel-fed and automatic transmission cars appear to need more transmission fluid than the more remote cars. In much the same way, manual-transmission models require less transmission fluid than semi-automatic and automatic models.
There’s also a big difference in how much transmission fluid you need to add, depending on whether you are doing a transmission flush versus a dry fill or service fill.
In short, a transmission flush purges (or flushes) your vehicle of transmission fluid. While a dry or service fill, often referred to as a pan drop, will eradicate dirty fluid from the transmission pan, replacing it with fresh fluid that mixes with old but usable transmission fluid left in the car.
How Often Do I Need to Change Transmission Fluid?
Most manufacturers recommend performing fluid flushes every 30,000-60,000 miles for a manual car, and then 60,000-100,000 miles for an automatic car. Checks for automatic transmission fluid levels should be conducted at least twice a year for both.
However, when to change your transmission fluid ultimately depends on your specific vehicle make and model. Furthermore, the environment you’re driving in can affect the frequency. Any vehicles that are driven in severe driving environments, may require more frequent fluid change and inspection.
Tips For Changing Transmission Fluid
Changing the transmission fluid is a very messy job because there’s typically no drain plug to change the fluid, but you can do it yourself if you’re eager.
To change the fluid, you will have to get under the vehicle and remove the pan from the bottom of the transmission. As soon as you loosen the pan, transmission fluid will start to dribble out in all directions so it’s important to have a fairly large catch pan at the ready.
It’s also important to be aware that removing the pan doesn’t necessarily drain all of the old fluid out of the transmission. It’s estimated that around a third of the old fluid will still be in the torque converter.
On top of this, there’s no drain plug on the converter so you’re technically only doing a partial fluid change. Regardless, a partial transmission fluid change is better than no transmission fluid change at all.
A typical fluid change can require anywhere from 2.5 to 5.5 litres of automatic transmission fluid depending on the vehicle, along with a new filter and a pan gasket for the transmission pan.
The pan must be thoroughly cleaned prior to being reinstalled. This task will include wiping all fluid residue from the inside of the pan, scraping all traces of the old gasket from the pan’s sealing surface, and cleaning the mounting flange on the transmission.
When installing the new filter, you must make sure it is securely mounted in the exact position as the original was and that any O-rings have been properly positioned prior to tightening any of the bolts. Then you will be able to proceed to tighten the bolts to the manufacturer’s recommended specs.
Using a long-neck funnel with a built-in screen is recommended for refilling the transmission fluid, as this can help to avoid any dirt or debris entering.
Here’s a great YouTube demonstration on how to change the automatic transmission fluid.
FAQs (Frequently Asked Questions)
A typical fluid change can require anywhere from 2.5 to 5.5 litres (3 to 6 US quarts) of automatic transmission fluid, depending on the make and model of the vehicle. Some may require far more.
In general, it may only take around 3 to 6 quarts of transmission fluid to fill up your transmission. Although it holds a lot more than this, a lot of the quarts of transmission fluid will be in the torque converter.
