Banging during gear shifts
Older Renault with a four-speed transverse automatic transmission, labeled as DP0, have a fairly common gear shift issue.
It will manifest itself as a harsh gear change that comes in combination with a loud bang.
In more severe cases, there will trigger a ‘check gearbox’ warning on the dashboard. This problem usually shows up only after the vehicle warms up and tends to be intermittent.
- Fluid leaks within the pressure regulator, which has the task of ensuring that the transmission fluid pressure is within specifications. This happens as the spring inside the regulator becomes weak, resulting in a loss of hydraulic pressure and harsh shifts. The solution to this problem is a new and upgraded regulator.
- Clogged lock-up solenoids, which obstruct their movement and causes delays during gear changes. The harsh engagement happens as a result of different speeds between gears.
Switching to limp mode
Another common problem that affects many older Renaults with a four-speed transverse automatic transmission, designated as DP0, is a sporadic engagement of limp mode.
In most cases, the car runs and shifts fine for several miles after startup but switches into limp mode as it warms up. In this mode, the transmission will stay stuck in 3rd gear, and there will be a ‘Gearbox faulty’ dashboard warning.
- Low transmission fluid level, which triggers a limp mode as a preventive measure to prevent the damage caused by overheating and lack of lubrication.
- Faulty pressure modulation valve, causing increased differences in transmission fluid pressure during gear changes. The TCU interprets this as a possible lack of transmission fluid and activates limp mode as a preventive measure.
Rattling noise while accelerating
Several Renault models come with a Continuously Variable Transmission sourced from Jacto. These transmissions have a very common problem that shows up as a whining or rattling noise. This may be intermittent or constant but usually happens only during acceleration.
In some cases, there might be noticeable shaking. There will be no other symptoms or warning lights.
- Broken or worn down pulley bearing, which is a fairly frequent issue with these transmissions. As there are two pulleys, primary and secondary, narrowing down the source of the noise requires a test drive in specific conditions. While coasting at speed with the noise being the loudest, shift the transmission into a lower ratio. Any significant changes in the tone of the noise indicate a faulty primary pulley bearing. Otherwise, the problem is with secondary pulley bearing. Replacing faulty bearings with aftermarket upgraded ones solves the issue.
Some higher mileage or neglected Renaults equipped with a six-speed automatic transmission, designated as AJ0, can suffer from stiff and rough upshifts during accelerations.
An additional symptom is a severe lurch that happens when trying to shift from Neutral to Drive or Reverse. In the beginning stages, these symptoms might only occur until the car reaches running temperatures and will not trigger any warning lights.
- Excessive wear inside solenoid valves, which causes fluid leaks and corresponding pressure drops. Also, mechanical wear can obstruct the solenoid movement. The lack of smooth and controlled solenoid movements causes harsh gear shifts. Replacing all solenoid valves at once is the best solution.
Judder and rattle on idle or when shifting gears
Newer Renaults that have a 6-speed dual-dry-clutch automatic transmission, designated as 6DCT250, can have a problem with rattling, juddering, or even shuddering.
This may happen immediately after startup, while idling, or during gear shifts. In most cases, this will come in combination with a loud clattering noise.
- Excessive wear and play within the dual-mass flywheel, causing a metallic rattle while idling. Check the fly-wheel condition and replace it if there is any movement between the two plates.
- A worn dual-clutch assembly as a result of normal wear-and-tear. Although there are repair kits that allow partial repair, replacing the whole clutch assembly is usually the best solution.
These symptoms may affect Renault Clio, Scenic, Megane, Kangoo, Rafic. More important than the Renault model is the transmission model. To properly research and troubleshoot a Renault vehicle, you need to find out the transmission model installed on your car.
These are some of the most common Renault transmission problems based on the YOUCANIC team experience and research. It doesn't mean that all Renault vehicles have transmission problems.