The Opel AR25 4-speed automatic transmission was assembled in Strasbourg from 1988 to 2003 and installed in rear-wheel drive models such as the Senator and first- and second-generation Omega. This automatic transmission is essentially a variant of the popular General Motors 4L30 automatic.
Specifications
| Type | automatic transmission |
| Number of gears | 4 |
| Type of drive | rear |
| Engine volume, l | up to 3.0 |
| Torque output, Nm | up to 250 |
| Recommended oil | ATF Dexron VI |
| Oil capacity, liter | 8.7 |
| Partial replacement, liter | 4.5 |
| Maintenance | every 60 000 km |
| Gearbox lifespan, km | ~300 000 km |
| Weight, kg | 75 |
Gear ratios Opel AR25
Using the example of a 2000 Opel Omega with a 2.2 liter engine:
| Main | 4.22 |
| 1st | 2.856 |
| 2nd | 1.618 |
| 3rd | 1.000 |
| 4th | 0.723 |
| Reverse | 2.000 |
Using
The transmission was installed on:
- Opel Omega A (V87) in 1988 – 1994
- Opel Omega B (V94) in 1994 – 2003
- Opel Senator B (V88) in 1989 – 1993
Disadvantages of the Opel AR25 gearbox
- This is a fairly reliable automatic transmission, but it can cause problems with high mileage;
- It all starts with wear on the torque converter clutches, which spreads throughout the system;
- This dirt clogs the Overdrive valve body solenoids and even corrodes their wiring;
- When the torque converter clutches are severely worn, shaft vibrations can damage the oil pump bushing;
- There are also frequent complaints on specialized forums about gear selector failures.
