The company produced the 2.9-liter Volvo B6294S gasoline engine from 1998 to 2001, but it was only used on the S80 model prior to restyling, particularly in many of these American-made vehicles. In essence, this power unit is just an upgraded version of the popular B6304S motor.

The B6284T, B6294T, and B6304S are members of the 6-cylinder modular engine family.
The engine was mounted on:
- Volvo S80 I (184) in 1998 – 2001.
Specifications
| Production years | 1998-2001 |
| Displacement, cc | 2922 |
| Fuel system | injector |
| Power output, hp | 204 |
| Torque output, Nm | 280 |
| Cylinder block | aluminum R6 |
| Block head | aluminum 24v |
| Cylinder bore, mm | 83 |
| Piston stroke, mm | 90 |
| Compression ratio | 10.5 |
| Features | DOHC |
| Hydraulic lifters | yes |
| Timing drive | belt |
| Phase regulator | at the intake |
| Turbocharging | no |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 6.9 |
| Fuel type | petrol |
| Euro standards | EURO 3 |
| Fuel consumption, L/100 km (for Volvo S80 2000) — city — highway — combined |
15.2 8.4 10.9 |
| Engine lifespan, km | ~330 000 |
Disadvantages of the B6294S engine
Magneti Marelli’s whimsical electric choke is responsible for the majority of the issues;
Oil leaks from the phase control system rank second in terms of complaints;
Here, lubrication consumption is also frequently caused by clogged crankcase ventilation;
Because the valves bend when the timing belt breaks, it is essential to keep an eye on its condition;
The thermostat, fuel pump, pump, and engine mounts are additional weaknesses.
