Aisin TF-80SC: Oil Change Interval and Common Issues

If you are into technical details of vehicles, you are going to like my today's article since I'm going to tell you more about the Aisin TF-80SC transmission (also known as General Motors AF40-6). This is a legendary automatic transmission that survived almost 18 years on the market with no major changes in its engineering.

TF-80SC transmission highlights

• Average lifespan:190,000-220,000 miles
• Reliability Score:Medium
• Prone to minor issues:Seldom
• Price for repair after failure:$1,200-$1,600
• Price for replacement:$2,900-$4,500
• Availability of parts:Good
• Common problems: Valve body problems, torque converter problems, cooling issues, bearing issues.

What should you know about the Aisin TF-80SC transmission?

This unit was first offered on the market in 2001. It was made by Aisin for a whole lot of car models and it had pretty all-purpose specs so it could suit a small Chevrolet Cruze and a big Volvo XC90. Literally dozens of cars started implementing this transmission in the 2004 model year and it was used up to 2015 actively. Some models had this unit even in 2018.

The transmission could be used in front- and all-wheel drive cars. It was known under different codes. While some manufacturers used the TF-80SC code from Aisin, Peugeot-Citroen implemented its own code name - AM6. While General Motors used the AF40-6 code for this transmission.

Here are the key things to know about it:

• this is the conventional automatic 6-speed transmission used in all- and front-wheel-drive cars all over the world;
• it was completely engineered and made by the Aisin company in Japan;
• it could be used with the engine up to 4.4 liters of displacement and up to 330 lb-ft of torque;
• the overall weight is 87 kilos or 190 pounds;
• there was a modification TF-81SC that was even used by Land Rover and Jaguar;
• the transmission wasn't modified seriously and saved its initial engineering till its death in 2018;
• it's pretty complicated in terms of proper servicing - the filter can only be replaced when the transmission is taken apart.

One of the very important advantages of this automatic transmission is that it's pretty widespread. You can easily buy affordable parts for repair. Also, the transmission is available used/refurbished at a very good price compared to other modern automatic transmissions.

But still, the first years are commonly known to be pretty problematic. With their minor problems, they will get on your nerves regularly and some of them can quickly grow to fatal issues requiring expensive repairs. So, I can't say this unit is perfect (as well as any other transmission in the modern world).

What about the durability of the Aisin TF-80SC?

Reportedly, this transmission can last about 200,000 miles. This is not bad for an automatic gearbox and this is just the average estimate. So, if you maintain it perfectly and never overload, you will most likely be able to take it further than that.

Also, durability depends on many factors like the year, the type of fluids you put into it, the quality and intervals of regular maintenance, the type of use, etc.

When this transmission fails, you have a choice of repairing it paying at least $1500 for this, or replacing it with a new one (usually the used one) for adding more miles to your car. Fortunately, parts are not that expensive. But the labor costs are still very unpleasant.

How often should you change the oil in this transmission?

Now, the central factor that defines the longevity of this unit is fluid change. Depending on the car brand that you have, you may find numerous recommendations for the type of fluid. Toyota ATF WS is known to be the perfect choice for this unit. But you can use anything that the manufacturer of your car recommends.

The funny thing - you will find little to no information about transmission fluid change. Aisin basically says nothing about maintenance and you can conclude that this transmission doesn't require oil change. It's wrong and this can lead to a very short life - about 100,000 miles before your gearbox dies.

Here are the important maintenance tips from me (after speaking to several transmission mechanics):

• it's a good practice to change the fluid in this transmission about once every 40,000 miles;
• the filter may be changed once per three oil changes because the procedure is very labor-intensive;
• you will need about 4 liters of ATF - better take the Toyota ATF WS or Aisin AW-1;
• also, you will need the drain plug seal - it should be changed every time you change the fluid;
• the level can't be changed easily because there is no dipstick, so just don't miss the regular fluid change.

Overall, the Aisin TF-80SC has about 7.2 liters of ATF in it but as with all conventional automatic transmissions, the entire volume can't be changed. About 4 liters will be changed during standard service.

Once every 100,000 or 120,000 miles, you will need to change the filter, too. This is when you can change all the fluid because the transmission will be taken apart.

What are the best and worst years of the Aisin TF-80SC?

Clearly, the best years are the later ones. I would say, after 2010 this transmission became much more reliable and got rid of many of its initial problems.

In its first years, the transmission had a pretty bad torque converter with faulty friction plates that could get loose and affect the pump. If you don't react timely, the transmission will just stop working completely once.

On more powerful engines like in the Volvo SUV models, this transmission lives a much shorter life due to overloading. Friction plates are worn out faster and send a lot of metal shaves directly to the fluid and they then clog the valve body units. That's why changing fluid is so important. This is true for all model years.

Also, the transmission has a so-so heat exchanger in all model years and it can overheat leading to jerking when shifting. A lot of Cruze owners came to me with a jerking transmission and I ended up installing an additional radiator for the transmission fluid. This solved all the problems without any other repairs.

Other than that, there are almost no serious common problems that you could connect to model years. So, I would recommend staying away from these transmissions made before 2010. But everything that was made after that, is pretty reliable and won't cause a lot of problems.

What else can you do to prolong the life of the Aisin TF-80SC transmission?

Well, this transmission is not made for sport, so aggressive driving is not a good option. When you start driving aggressively, it overheats and the clutch plates will wear out extensively. This leads to fluid contamination with friction plates' material and the transmission may easily get clogged.

Also, I strongly recommend against towing anything heavy with this transmission. Again, it will lead to serious overheating which is the deadly thing for this unit. You can tow some light trailers but if you decide to tow your big boat with your Volvo equipped with the Aisin TF-80SC, you need to understand the risks.

The heavier your vehicle, the calmer your driving style. This is the rule of thumb for this Aisin 6-speed automatic transmission. For the Cruze, it's more than just good. But if you own something much heavier than the Cruze, then it may be very questionable in terms of durability. Be careful and never kill your transmission by overloading it.

Excessive heat is the number one culprit of problems, so you may want to install the additional cooler for transmission fluid which is perfectly possible in this model. The standard heat exchanger is ridiculously small and ineffective.

Final thoughts

Although I've found some serious common problems connected with the Aisin TF-80SC transmission model, I still think this is one of the best affordable automatic transmissions. It was used in literally dozens of models and it can live over 200,000 miles without serious and expensive repairs.

Also, even if it's broken, you can repair it without breaking the bank. It's not that easy to locate the problem when something happens with this transmission, but actually, the engineering is pretty simple, so you can get it repaired in almost any independent repair shop.

Still have any questions? Write in the comments below!