I. Driver's Perspective: A Genuine Transformation from 'Reluctant to Drive' to 'Effortless Operation' At a municipal sanitation department parking lot in Ningbo, Zhejiang, driver Lao Zhang has just completed a round of rainy-season sludge suction operations. He is operating a Chengli-Dongfeng single-cab blue license plate sludge suction truck with a 5 m³ capacity, chassis model CLW5070GSSD6 (based on the Dongfeng DOLICA chassis). Lao Zhang says: 'Driving older sludge suction trucks was tough—stiff steering wheel, poor visibility, and especially in Ningbo’s humid, rainy climate, rust easily formed inside the cab and sealing strips aged quickly. But this vehicle is completely different.' What Lao Zhang refers to as 'different' manifests in three key aspects: First, the steering wheel features hydraulic power assist, enabling effortless one-handed operation—unlike older models requiring forceful two-handed steering. Second, the cab offers an expansive field of view with minimal A-pillar blind spots, significantly boosting driver confidence during reversing and turning maneuvers in narrow streets or residential neighborhoods. Third, the vehicle employs high-performance anti-corrosion coating and premium-grade sealing components; after multiple heavy-rain operations, no rust or water leakage has been observed inside the cab. 'The handling performance is what impresses me most,' adds Lao Zhang. 'The clutch pedal is light, gear shifts are short-travel, and paired with the 5-speed manual transmission, stop-and-go traffic in congested urban areas feels far less fatiguing. Our unit has received five units total, and fellow drivers consistently report how intuitive and easy this vehicle is to operate.' II. Operational Convenience: C-Class Drivers Can Operate It Effortlessly For municipal sanitation departments, driver licensing profiles represent a critical procurement consideration. While many veteran drivers hold Class B or Class A licenses, newly hired younger staff often possess only Class C licenses. This Chengli-Dongfeng single-cab blue license plate sludge suction truck weighs under 4.5 tons—fully compliant with blue license plate regulations—and can therefore be legally operated with a Class C1 driver’s license. In practical use, operational convenience is evident in the following features: Steering System: Hydraulic power-assisted steering ensures light, precise handling—even female drivers find it easy to maneuver. Braking System: Equipped with either air brakes or hydraulic brakes (depending on configuration), delivering responsive, stable braking performance even on wet, slippery roads during rainy conditions. Visibility Design: The cab adopts a cab-over-engine (flat-nose) layout with a large front windshield, complemented by oversized side mirrors and blind-spot mirrors—effectively eliminating vision dead zones. Control Layout: Hydraulic valves and pump switches essential for sludge suction operations are ergonomically grouped near the center console within easy reach—no need to exit the cab for operation. 'We have several young colleagues who obtained their Class C licenses less than a year ago; they adapted fully to driving this vehicle within just two or three days,' notes Wang Shifu, fleet manager at a local subdistrict environmental maintenance unit. 'Previously, we had to assign experienced drivers for mentoring—but now that’s largely unnecessary.' III. Class C License Learning Curve: Real-World Test Confirms Proficiency Within 3 Days To objectively assess the learning curve, we conducted a small-scale field test in collaboration with a municipal sanitation department in Ningbo. Three drivers participated: two held Class C1 licenses but had zero prior experience operating special-purpose vehicles; the third held a Class B2 license but had exclusively driven passenger cars for years. Results were as follows: Day 1: All three completed static familiarization (instrument panel, control buttons, hydraulic system oper