Explore our foundational range of heavy-duty engine, hydraulic, and specialised transmission formulations designed for severe service environments.
Manual transmission systems remain the backbone of heavy commercial transit, construction vehicles, and high-precision mechanical drivetrains worldwide. The mechanical stress encountered inside a modern manual gearbox is highly complex. Gear meshes face continuous boundary lubrication regimes, high sliding velocities, and heavy surface loading. Choosing a premium, high-shear manual gearbox oil is not just about reducing wear; it directly dictates the efficiency, longevity, and thermal profile of the entire mechanical driveline.
Under heavy duty conditions, the gear teeth surfaces experience extreme pressure. Inadequate film strength can cause micro-welding, scuffing, and progressive pitting. This highlights the vital importance of advanced anti-wear additives. Formulating manual transmission fluids (MTFs) requires balancing extreme pressure (EP) additives with syncromesh friction modifiers. Traditional gear oils designed for rear axles (such as standard GL-5 fluids) contain highly active sulfur-phosphorus additives that can corrode copper-based synchronizer rings. Thus, highly specialized manual gearbox oils must offer specialized synchronizer protection alongside reliable EP protection.
"A modern manual transmission fluid must maintain a highly stable dynamic coefficient of friction (typically between 0.09 and 0.12) across its lifetime. This ensures smooth gear synchronization while avoiding synchronizer slippage or premature wear."
At Shandong Longhai Lubrication Technology Development Co., Ltd., our R&D team analyzes driveline dynamics at a molecular scale. The performance of manual gearbox oils is dictated by two primary components: the base oil quality and the additive chemistry.
The global shift in transportation and heavy industry requires lubricants that meet diverse operational standards. In heavy logistics, fleet operators need lubricants that support longer oil drain intervals (ODIs) to reduce downtime and maintenance costs. Our formulations are engineered to meet extended drain specs (up to 120,000 km in qualified commercial systems) while safeguarding transmission components.
In construction and agricultural machinery, gearboxes are exposed to dust, moisture, and high shock loads. These systems require excellent water separation (demulsibility) and rust prevention. Our manual gearbox oils are formulated to quickly separate water contaminants, protecting steel and copper alloys from rust and corrosive wear.
Shandong Longhai Lubrication Technology Development Co., Ltd. is a modern lubrication enterprise equipped with advanced manufacturing infrastructure.
Established in 2009 in Zibo, Shandong, Shandong Longhai Lubrication Technology Development Co., Ltd. has developed a complete, vertically integrated production chain. We operate our domestic brand "Century Longhai" alongside the international strategic brand British "A Ba", providing diverse product lines to global commercial markets.
Our production facilities feature high-precision automatic blending systems and automated filling lines. This equipment achieves a filling accuracy of 1‰-2‰ and increases production speed by 20% to 35% compared to semi-automated lines. These capabilities enable us to maintain consistent quality and meet high-volume global delivery schedules.
Our formulations are verified to perform under extreme load conditions while complying with global safety, quality, and environmental regulations.
We are certified to ISO 9001:2015 for quality management, ISO 14001 for environmental management, and ISO 45001 (OHSAS 18001) for occupational health and safety.
Our products are backed by PICC (People's Insurance Company of China) quality insurance and meet key global OEM specifications, including Mercedes-Benz approvals.
Explore our research laboratories, quality control units, and strategic development centers that support our lubricant engineering.
Our production base adheres to environmental standards, with enclosed pipelines and air filtration systems. Our 131-acre manufacturing footprint integrates raw material storage, computerized blending control rooms, and automated packaging lines.
Explore Heavy Gear Oil Solutions
How Shandong Longhai is developing specialized fluids for modern automotive and industrial drivetrains.
We are engineering ultra-low viscosity fluids (such as 70W and 75W fluids) to reduce hydrodynamic losses in modern manual transaxles. This supports lower fuel consumption and carbon emissions while maintaining high film strength.
For hybrid manual gearboxes and electric drive units (EDUs), we are developing transmission fluids with balanced electrical conductivity, copper protection, and cooling performance to prevent dielectric breakdown under high voltage.
To support forestry, marine, and environmentally sensitive projects, we formulate biodegradable industrial gear oils and manual transmission fluids using synthetic esters that break down quickly in soil and water.
We are testing oil additives that react under localized heat to form a protective layer on gear surfaces. This protects gear teeth from damage during heavy loads or low-speed operations.
Our structured development process ensures tailored formulation design, testing, packaging, and supply chain logistics for custom applications.
We review your technical specifications, operating conditions, target market requirements, and compliance standards (API, ACEA, JASO).
Our laboratory selects appropriate base oils and additive chemistry to create target formulations for validation.
We evaluate trial batches using standardized tests (such as ASTM D130 copper corrosion, FZG scuffing, and four-ball wear test) to verify fluid performance.
We transition to full-scale automated blending, package filling, labeling, and logistical dispatch to target international hubs.
We provide ongoing batch consistency tracking, oil analysis services, and formulation updates to match changing market needs.
Technical guidance from our research laboratory to address common issues in driveline lubrication and maintenance.
Extreme pressure (EP) additives containing active sulfur and phosphorus form a protective layer on steel gear teeth. However, at high temperatures, these compounds can corrode copper-based synchronizer rings. Over time, this corrosion leads to synchronizer wear and rough shifting. For gearboxes with copper alloys, it is critical to use specialized MTF formulations that protect both steel and yellow metals.
API GL-4 oils typically contain about half the concentration of sulfur-phosphorus EP additives found in GL-5 oils, making them suitable for synchronizers in manual gearboxes. API GL-5 oils are formulated for high-load hypoid differentials and contain more active EP additives, which can cause chemical wear on copper components if used in standard manual transmissions.
Gear systems subject lubricants to intense mechanical shear. If the viscosity index improvers are not shear-stable, their molecular chains can break, causing the oil to lose viscosity. This thinning compromises the protective oil film, increasing the risk of metal-to-metal contact, gear wear, and noise.
Thicker oil provides high film strength but increases drag and energy loss, lowering fuel efficiency. It can also delay synchronizer engagement in cold conditions, leading to stiff shifting. Modern low-viscosity fluids (such as 75W-80) are engineered to reduce friction losses and improve cold shifts while maintaining wear protection under load.
Key indicators include increased shifting effort (especially when cold), gear noise, or metal shavings in the fluid. Analytical laboratory testing can identify oil oxidation (color darkening, acid number increase), viscosity loss, and contamination (such as water or high levels of wear metals like copper and iron).
Explore our industrial gear, anti-wear hydraulic, gasoline engine, and specialized compressor oils formulated for commercial operations.
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