The 5-speed automatic in your 2020 Mitsubishi Pajero should shift smoothly and imperceptibly under normal driving. When shifts become harsh, jarring, or clunky, something has changed in the transmission's operation. Understanding the causes helps you determine if a simple service might help or if more significant repairs are needed.
Symptoms of Harsh Shifting
- Hard or jarring shift between gears
- Clunking sound during gear changes
- Vehicle jerking during shifts
- Delayed engagement when selecting gear
- Shifting at wrong RPM
- Transmission slipping then engaging harshly
- Harsh shifts when cold that improve when warm
Common Causes of Harsh Shifting
Transmission Fluid Problems
Transmission fluid degrades over time, losing its friction-modifying and hydraulic properties. Low fluid or old fluid often causes harsh shifts.
Solutions:
- Check fluid level (while warm, per procedure)
- Inspect fluid condition (should be red/pink, not brown or burnt-smelling)
- Perform transmission fluid and filter service
Solenoid Issues
Shift solenoids control hydraulic pressure to engagement clutches. Failing solenoids can't apply clutches smoothly.
Solutions:
- Scan for transmission codes identifying specific solenoid issues
- Solenoid replacement (often can be done without full transmission removal)
Valve Body Problems
The valve body is the "brain" of hydraulic control. Worn valves, stuck check balls, or accumulated debris cause erratic hydraulic pressure.
Solutions:
- Valve body replacement
- Valve body rebuild (less common)
Worn Clutch Packs
Internal clutch packs wear over time. Worn clutches may slip then grab harshly as they engage.
Solution: Transmission overhaul or replacement if clutches are significantly worn.
Engine or Transmission Mounts
Worn mounts allow excessive drivetrain movement, making normal shifts feel harsh as the powertrain lurches.
Solution: Inspect and replace worn mounts.
Software Calibration
Transmission shift points and pressure are software-controlled. Updates may improve shift quality.
Solution: Check with dealer for transmission software updates.
Diagnosis Steps
- Check fluid: Level and condition are the first things to verify
- Scan for codes: Transmission codes may identify specific issues
- Note patterns: Which shifts are harsh? Is it worse cold or hot?
- Check mounts: Visual inspection for collapsed or broken mounts
- Test drive: Professional evaluation of shift quality
- Check for updates: Software updates may address shift calibration
When Fluid Change Helps
If fluid is dark or burnt-smelling, and the transmission doesn't have severe internal damage, a fluid and filter service may significantly improve shift quality. However, very old transmissions with significant wear may actually shift worse after fluid change (fresh fluid can't compensate for worn parts the way contaminated fluid did).
Repair Costs
- Transmission fluid and filter service: $150-$350
- Transmission software update: $100-$200
- Motor/transmission mount replacement: $200-$500 per mount
- Solenoid replacement: $300-$800
- Valve body replacement: $800-$1,800
- Transmission rebuild: $2,500-$4,500
- Transmission replacement: $3,500-$6,000
Early attention to harsh shifting may prevent more expensive repairs. A simple fluid service is worth trying before assuming major transmission work is needed.