ما الفرق بين زيت التروس GL4 و GL5 لسيارات الإمارات؟

[PatrickRose]

For most modern GCC-spec vehicles in the UAE, GL-4 is the safe choice for manual transmission gearboxes, while GL-5 is specifically formulated for differentials, especially in 4x4s. The core technical difference lies in the additive package: GL-5 contains much higher levels of extreme pressure (EP) additives, primarily sulphur-phosphorus compounds, to handle the sliding action and high shock loads in differentials. However, these same additives can be corrosive to the softer yellow metals (like brass synchronizers) found in many manual transmissions. According to vehicle maintenance guidelines referenced by the RTA Dubai, using an incorrect lubricant specification is a common factor in premature transmission wear. For example, a 2022 GCC-spec Toyota Land Cruiser manual specifies GL-4 for its manual gearbox and GL-5 for its front and rear differentials. The financial implication of a mistake is significant. A gearbox rebuild for a popular SUV like a Nissan Patrol can cost between AED 8,000 to AED 15,000 at a specialized workshop, not including downtime. Sticking to the manufacturer's manual, not the generic label on the bottle, is non-negotiable.

• Correct application prevents costly synchronizer damage.
• GL-5's high-EP additives are designed for differentials, not gearboxes.
• Always verify the specification in your vehicle's owner's manual first.

[WilliamRose]

I learnt this the hard way with my 2018 Toyota Hilux here in Sharjah. The mechanic put GL-5 in the gearbox saying it's "stronger." Within months, shifting became notchy, especially in the morning. Another garage confirmed the synchronizers were getting damaged from the corrosive additives. Switched back to proper GL-4, and it improved, but some damage was done. Now I always show them the manual page myself.

[JoyRose]

In our Al Quoz workshop, we see this confusion weekly. People think a higher number means better protection, which is wrong for gearboxes. For most daily drivers like the Toyota Corolla or Nissan Sunny with manual transmission, the factory fill is always GL-4. Using GL-5 can silently degrade shifting smoothness over 20,000-30,000 km. The rule is simple: gearbox (manual) = GL-4; differential = GL-5. For modern automatics, they use entirely different ATF fluids anyway.

[VanColeman]

As a used car manager in Dubai, a clean service history with correct fluid specs like GL-4 vs. GL-5 matters. We check it. A car that's had the wrong gear oil often has a slightly rougher gear shift, which savvy buyers notice. It can knock AED 1,500-2,500 off the resale value of a sedan like a Camry because it signals potential future transmission issues.

[Juniper]

For off-roading in the desert near Liwa, GL-5 in the differentials is critical—it handles the extreme shock loads from dunes. But never in the gearbox. The high summer heat (45°C+) already stresses the transmission; adding the wrong oil accelerates wear. I use a dedicated GL-5 75W-90 in my Patrol's diffs and a fully synthetic GL-4 for the gearbox. It's a small cost for long-term reliability in our conditions.