P0788 — 4-5 Shift Malfunction
Drivable short-term, but fix now to avoid damage.
What P0788 means
This code means the transmission control system detected a fault completing the shift between 4th and 5th gear. It's commonly caused by a faulty shift solenoid, low or dirty transmission fluid, or worn internal clutches, with wiring and control module problems also possible. Fixes range from a simple fluid service or solenoid replacement to more extensive internal transmission repair.
Common symptoms
- Check engine light is on
- Harsh or delayed shift between 4th and 5th gear
- Transmission slipping or high RPM at highway speeds
- Stuck in a lower gear or limp mode
- Reduced fuel economy and poor highway performance
Common causes
- Faulty 4-5 shift solenoid
- Low, dirty, or burnt transmission fluid
- Worn clutch packs or internal transmission wear
- Damaged wiring or connectors to the solenoid
- Failing transmission control module
Typical repair cost
$150 – $2500
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0788 code?
For short distances, usually yes, but don't rely on it. The transmission can be damaged further if you keep driving with shift problems, so get it inspected soon and avoid extended highway or heavy driving.
How much does it cost to fix a P0788 code?
It depends on what's wrong. A fluid service or solenoid replacement may cost a few hundred dollars, while internal transmission repairs can run well over two thousand dollars.
Is a P0788 code serious?
Yes. While the car may still drive, a shift malfunction can lead to costly transmission damage if left unaddressed, so it's a higher-priority repair.
Why does my engine rev high on the highway with a P0788?
If the transmission can't shift into 5th gear, the engine stays at higher RPM at highway speeds. This hurts fuel economy and means the transmission isn't reaching its top gear until the fault is fixed.