The Aisin AW81-40LS 4-speed automatic transmission was produced from 2002 to 2020 and was installed in numerous Chevrolet Lacetti clones, such as the Daewoo Nubira and Buick Excelle. This transmission is rare, as it was installed in Asian-spec models.
Specifications
| Type | automatic transmission |
| Number of gears | 4 |
| Type of drive | front |
| Engine volume, l | up to 1.6 |
| Torque output, Nm | up to 150 |
| Recommended oil | Toyota ATF Type T-IV |
| Oil capacity, liter | 5.6 |
| Partial replacement, liter | 2.5 |
| Maintenance | every 60 000 km |
| Gearbox lifespan, km | ~300 000 km |
| Weight, kg | 60 |
Gear ratios Aisin AW81-40LS
Using the example of a 2007 Chevrolet Lacetti with a 1.6 liter engine:
| Main | 3.836 |
| 1st | 2.875 |
| 2nd | 1.568 |
| 3rd | 1.000 |
| 4th | 0.697 |
| Reverse | 2.300 |
Using
The transmission was installed on:
- Buick Excelle 1 (J200) in 2003 – 2016
- Chevrolet Lacetti 1 (J200) in 2004 – 2013
- Chevrolet Optra 1 (J200) in 2004 – 2019
- Daewoo Lacetti 1 (J200) in 2002 – 2009
- Daewoo Nubira 2 (J200) in 2002 – 2009
Disadvantages of the Aisin AW81-40LS gearbox
- This is a fairly reliable transmission, but its service life is highly dependent on operating conditions;
- Frequent abrupt starts wear out the linear pressure solenoid in the valve body;
- Then the oil pressure in the system drops, and the clutch packs begin to burn;
- After 200,000 km, the oil pump seal often leaks, which doesn’t improve service life;
- The thrust bearing housing also sometimes slips due to weakening of its locking mechanism;
- The short-lived plastic speedometer drive gear is also criticized on forums;
- Wear of the Teflon rings in the rear cover is typical for all automatic transmissions in this line.
