Gearbox Aisin TF-70SC

The 6-speed automatic transmission Aisin TF-70SC was produced in Japan from 2007 to 2024 and was installed on a number of front-wheel drive Peugeot-Citroen models under its index AT6. This transmission is also often found on Fiat cars for the American market.

Specifications

Description

In 2006, the Japanese concern Aisin released a simplified version of its bestseller TF-80SC. This 6-speed gearbox was developed for front-wheel drive Peugeot-Citroen models and was aggregated with gasoline engines and transverse diesel engines up to 300 Nm. Structurally, this is a fairly classic hydromechanical automatic transmission, built around the planetary scheme according to Lepelletier: a simple planetary gearbox plus a double one from Ravigneaux.

An updated modification of the transmission with a slightly different valve body appeared in 2009. In 2013, a new version of the TF-71SC gearbox debuted, on PSA models it was called EAT6. Then a modification for front-wheel drive BMW and Mini appeared with its own index TF-72SC, and there was also a simplified version of the TF-73SC automatic transmission for the lowest-power cars.

Gear ratios Aisin TF-70SC

Using the example of a 2009 Peugeot 3008 with a 1.6 THP turbo engine:

Using

The transmission was installed on:

• Changan CS75 1 (S301), CS75 Plus 1 (S311), Raeton 1 (CD101);
• Citroen C4 I (B51), C4 II (B71), C4 Sedan I (B5), C4 Picasso I (B58), C5 II (X7), DS3 I (A55), DS4 I (B75), DS5 I (B81) (as AT6);
• Dongfeng AX7 I (G29);
• Fiat 500 II (312), 500C II (312), 500L II (351), Tipo II (356);
• Jeep Compass 2 (MP), Renegade 1 (BU);
• Geely Jiaji 1 (VF11);
• Peugeot 208 I (A9), 308 I (T7), 408 I (T73), 508 I (W2), 2008 I (A94), 3008 I (T84), 5008 I (T87), RCZ I (T75) (as AT6).

Service regulations

Although there is no regulation on oil change in the gearbox, it is advisable to renew it every 60,000 km. The system is filled with 6.8 liters of lubricant from the factory, and for a partial replacement, 3.0 to 4.0 liters are needed. Oils with ATF JWS-3324 approvals are used, for example, Aisin AW-1 or the original Toyota WS.

Disadvantages of the Aisin TF-70SC gearbox

Valve body

This is a reliable automatic transmission and with regular oil changes it causes a minimum of problems. However, if it is not serviced, the valve body solenoids will become clogged with wear products of the torque converter lockup clutch and the automatic transmission will start to push already by 150,000 km.

Heat exchanger

This automatic transmission is equipped with a tiny heat exchanger, which becomes clogged already by 100,000 km and the box simply begins to constantly overheat, which greatly reduces its service life. Service technicians recommend installing an external cooling radiator through an adapter.

Mechanical part

On runs over 200,000 km, Teflon sealing rings often wear out and the lubrication pressure in the system drops, which leads to grinding of the planetary washers. A preventive overhaul of the gearbox with the replacement of all rings and gaskets will help to avoid this.

The manufacturer stated the service life of the TF-70SC gearbox at 200,000 km, but this automatic transmission lasts 300,000 km.