Upgrading the exhaust system is one of the most common and effective supporting modifications for the D22 Navara YD25, particularly once tuning or turbo upgrades are introduced.
The factory exhaust is adequate for stock power levels, but becomes restrictive as airflow and boost increase.
Typical Upgrade – 3″ Turbo-Back Exhaust
The most common upgrade is a 3-inch turbo-back exhaust system, replacing:
- The factory dump pipe
- Catalytic converter (where applicable)
- Rear exhaust sections
A properly designed 3″ system reduces post-turbine restriction and allows the turbocharger to operate more efficiently.
“Too Big” Doesn't Apply to Turbo Engines
On turbocharged engines, there is effectively no such thing as too large of an exhaust within practical packaging limits.
The turbocharger itself provides all the back pressure the engine requires. Reducing restriction after the turbine:
- Improves turbo efficiency
- Reduces exhaust gas temperatures (EGTs)
- Improves throttle response
- Supports higher boost levels safely
For tuned vehicles, this becomes even more important.
Catalytic Converter and Mufflers
For most applications, we recommend:
- Retaining a catalytic converter
- Running one small muffler
This setup:
- Maintains legality in most regions
- Reduces excessive drone
- Keeps the exhaust note deeper but refined
- Avoids the harsh “straight pipe” sound
It provides a good balance between performance and comfort.
Quality and Fitment
There are many brands available on the market. As with other platforms:
- Cheaper systems can have poor fitment
- Inferior welds may crack over time
- Clearance issues can cause stress and vibration
Choosing a well-built system with good fitment history is important for long-term durability.
EGT Gauge Bung
When purchasing an exhaust system, it is highly recommended to choose one with a pre-installed EGT probe bung.
Even if you don't install a gauge immediately:
- The bung can be capped
- Adding one later is much easier
- Installing a bung with the exhaust already fitted can be inconvenient
Planning ahead makes future monitoring upgrades simple.
Is the Factory Exhaust Acceptable?
For a completely stock vehicle or very mild tuning, the factory exhaust can be sufficient.
However, once:
- Boost levels increase
- Turbo upgrades are installed
- Towing is common
- Higher sustained load is expected
an upgraded exhaust becomes strongly recommended.
Summary
- 3″ turbo-back exhaust is the typical upgrade
- Larger exhausts benefit turbocharged engines
- Turbo provides all necessary back pressure
- Retain a cat and small muffler for legality and comfort
- Choose quality brands to avoid fitment issues
- Install an EGT bung for future flexibility
- Factory exhaust is acceptable for mild setups but limiting for higher performance
For the D22 YD25, an exhaust upgrade is a foundational modification that supports both performance and reliability — especially when combined with tuning or turbo upgrades.