In recent days, China Auto Quality Network has continuously received complaints about the Dongfeng Ligent V3, with car owners reporting that the engine and transmission of this model have serious design flaws. According to statistics, China Auto Quality Network received 85 complaints regarding the Dongfeng Ligent V3, among which 19 complaints (22% of total) were related to engine problems, and 26 complaints (31% of total) were related to transmission issues.
For engines, the rocker arm detachment issue requires out-of-warranty owners to bear the cost themselves. Mr. Li from Shanxi complained on China Auto Quality Network: "The engine experienced severe shaking due to a cylinder misfire, which was caused by the valve rocker arm falling off and getting stuck in the exhaust valve. Upon inquiry, other car owners also reported similar problems." Mr. Li said that the staff at the 4S store claimed it was a common phenomenon, but the manufacturer did not initiate a recall, instead opting for a covert recall method mainly due to high costs. It was noted that vehicles within the warranty period would be replaced free of charge by the manufacturer, whereas those out of warranty or no longer covered would need to pay for replacements themselves.
China Auto Quality Network reporters learned that vehicles experiencing such problems were primarily concentrated on the 4G15M engine, produced by Dong'an Engine Factory. This problem is not universal; analysis of complaint cases from China Auto Quality Network revealed that the issues were mainly concentrated in vehicles manufactured before 2010, with the manufacturer subsequently improving the engines in later production. The Ligent V3 uses Mitsubishi's 4G15M technology engine, where M stands for MIVEC, the abbreviation for the variable valve timing system. This engine can adjust the lift and opening/closing sequence of the intake valves, increasing the lift at high-speed rotations. The main symptom of rocker arm detachment is difficulty starting the vehicle engine, unusual noises after ignition, unstable idling accompanied by intermittent vibrations, and severe cases may lead to engine shutdown. When driving, there might be noticeable vibrations while accelerating, feeling powerless, and an illuminated engine fault light. Vehicles showing these symptoms typically experience "clicking" noises between 500 and 2000 kilometers. This could be due to damage to the automatic timing belt adjustment component, causing misalignment of the timing chain and resulting in valve collision issues. Furthermore, according to China Auto Quality Network reporters, this also relates to uneven torque applied by workers during camshaft assembly at the Dong'an Engine Factory. If not adjusted in time, it could cause wear on the camshaft and pushrod. Coupled with inherent design defects in the valve rocker arm, this leads to its detachment.
Mr. Wang from Shaanxi complained on China Auto Quality Network: "Technicians at the 4S store indicated that many cars experience this symptom around 25,000 kilometers, attributed to design flaws. Only by replacing the improved valve rocker arm (with a retaining spring type) can the problem be resolved." According to China Auto Quality Network reporters, the manufacturer has identified the root cause, mainly improving the structure of the valve rocker arm and adding a retaining spring for fixation. However, based on feedback from car owners, if the problem occurs within the warranty period, the manufacturer offers free replacement of improved cylinder heads, but if out of warranty or no longer covered, owners must bear the cost themselves, with a complete cylinder head replacement costing over 10,000 yuan, and even just disassembling and replacing the valve rocker arm costing several thousand yuan. The reporter believes that since the manufacturer has already made improvements, it confirms that there are indeed certain quality issues with the product, making the warranty period irrelevant. If customers still have to bear the cost, it seems somewhat unreasonable.
In the complaints received by China Auto Quality Network, transmission noise problems are mainly concentrated in the Getrag transmission used with the Ligent V3's 4A91 engine. Mr. Zeng from Guilin complained that despite the 4S store replacing parts with counterweights, the noise problem persisted, strongly demanding that the manufacturer thoroughly resolve this issue. Many car owners reflected in their complaints that the 4A91 engine and the paired Getrag transmission have mismatch problems. Currently, the manufacturer adopts the method of adding counterweights to reduce noise.
According to China Auto Quality Network reporters, the transmission used in the Ligent V3 is produced by Jiangchi Manufacturing. The original dual-gear structure was changed to a single-gear structure, which altered the original transmission structure and natural frequency, causing uneven weight distribution in the transmission. Additionally, processing accuracy and clearance issues may also lead to noise problems. Currently, the manufacturer’s solution involves replacing slightly higher viscosity transmission oil and adding counterweights to balance the transmission weight, but these methods do not address the root cause. Due to mismatch issues leading to excessive vibration in the transmission and processing precision problems causing clearance, re-designing and adjusting the transmission structure and counterweights is necessary. If this problem is not completely resolved, it will directly affect the movement of the transmission input shaft, causing the crankshaft and input shaft to become misaligned, thereby damaging the clutch assembly, and severely leading to failure of the first-axis pressure bearing in the transmission. It is recommended that the manufacturer identify the fundamental cause and thoroughly resolve this issue.
Dongfeng Ligent has not yet proposed practical and feasible solutions for the problems encountered with the V3 model. For any car, the engine and transmission are the two most important components. If these critical components have quality defects, it will directly affect the quality and lifespan of the product. It is hoped that Dongfeng Ligent takes this matter seriously and soon provides an explanation to all car owners.
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