{"product_id":"ultra-1plus-75w-90-full-synthetic-gear-oil-sae-75w-90-gl-4-3-quart-jug-low-temp-flow-high-load-protection","title":"ULTRA 1PLUS 75W-90 Full Synthetic Gear Oil SAE 75W-90 GL-4 — 3-Quart jug, low-temp flow \u0026 high-load protection","description":"\u003cstrong\u003eULTRA 1PLUS SAE 75W-90 Full Synthetic Gear Oil (API GL-4) is a full-synthetic, all-season gear lubricant formulated to protect manual transmissions, differentials, and drivetrain gears under high load and temperature extremes.\u003c\/strong\u003e\n\n\u003cp\u003eEngineered from premium synthetic base stocks and advanced anti-scuff additives, this 75W-90 GL-4 gear oil meets SAE J306 viscosity and API GL-4 performance levels. It delivers consistent low-temperature flow for easier shifting, strong film strength under high torque, and enhanced resistance to oxidation, rust, and foaming. Packaged as a 3-quart jug for service and topping applications, it’s intended for passenger cars and light trucks that specify GL-4 or where friction characteristics must be maintained for synchronizers and limited-slip setups.\u003c\/p\u003e\n\n\u003ch3\u003eHow does this gear oil improve shifting and drivetrain feel?\u003c\/h3\u003e\n\u003cp\u003eULTRA 1PLUS 75W-90 uses friction modifiers and refined synthetic basestocks to balance smooth synchronizer engagement with gear protection. That reduces gear grinding and provides consistent shift feel across temperature ranges without compromising wear resistance.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eStable low-temperature viscosity for quicker oil flow at cold starts\u003c\/li\u003e\n  \u003cli\u003eFriction modifiers tuned for synchronizer compatibility\u003c\/li\u003e\n  \u003cli\u003eStrong film strength under high torque to prevent metal-to-metal contact\u003c\/li\u003e\n  \u003cli\u003eMinimizes gear noise and rough engagement\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat protection does it offer under heavy load or high heat?\u003c\/h3\u003e\n\u003cp\u003eDesigned for extreme-pressure applications, this GL-4 formula forms a resilient lubrication film that resists scuffing and wear even under repeated high-load conditions. Thermal and oxidation stability keep the lubricant effective longer, reducing varnish, deposits, and frequent service intervals.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAdvanced anti-scuff additives for high-load protection\u003c\/li\u003e\n  \u003cli\u003eSuperior oxidation resistance to limit viscosity breakdown\u003c\/li\u003e\n  \u003cli\u003eAnti-foam and rust inhibitors for cleaner internals\u003c\/li\u003e\n  \u003cli\u003eExtends gear and bearing life under sustained stress\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eIs this oil compatible with limited-slip differentials and synchronizers?\u003c\/h3\u003e\n\u003cp\u003eYes — the formula includes friction modifiers that maintain the correct shear characteristics for limited-slip differentials while remaining GL-4 compliant for synchronizer-friendly performance. It’s a cost-effective option where GL-4 chemistry is specified.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eLimited-slip compatible friction profile\u003c\/li\u003e\n  \u003cli\u003eAPI GL-4 certification ensures safe synchronizer operation\u003c\/li\u003e\n  \u003cli\u003eSuitable for many manual transmissions and transaxles\u003c\/li\u003e\n  \u003cli\u003eReduces the need for separate additives in most applications\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow do I know when to use ULTRA 1PLUS 75W-90 in my vehicle?\u003c\/h3\u003e\n\u003cp\u003eCheck your owner’s manual or service guide for API GL-4 or SAE 75W-90 recommendations. This product fits passenger cars and light trucks calling for GL-4 performance, particularly where smoother shifting and limited-slip compatibility are desired.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFollow manufacturer viscosity and GL-4 specifications\u003c\/li\u003e\n  \u003cli\u003eIdeal for manual transmissions, transaxles, and differentials\u003c\/li\u003e\n  \u003cli\u003eComes in a 3-quart jug suitable for top-offs or light service work\u003c\/li\u003e\n  \u003cli\u003eNot intended to replace GL-5 when GL-5 is explicitly required\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThis ULTRA 1PLUS SAE 75W-90 Full Synthetic Gear Oil balances all-season flow, high-temperature durability, and friction characteristics needed for modern gearboxes. It focuses on protecting gears, synchronizers, and bearings while reducing maintenance overhead through better thermal and oxidation resistance.\u003c\/p\u003e\n\n\u003cp\u003eWho is this for? Mechanics, DIY enthusiasts, and fleet operators who require an API GL-4 rated gear lubricant for passenger cars and light trucks will find this product appropriate. It’s particularly useful when the service specification calls for 75W-90 viscosity with synchronizer-friendly friction behavior or when limited-slip performance must be preserved. Always confirm compatibility with your vehicle’s service manual before use.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Can ULTRA 1PLUS 75W-90 be used in limited-slip differentials?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. The formula includes friction modifiers compatible with most limited-slip differentials while meeting API GL-4 requirements.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is this oil suitable for cold-weather use?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. The 75W low-temperature rating ensures reliable flow and easier shifting in cold starts.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"ULTRA 1PLUS","offers":[{"title":"Default Title","offer_id":48079923216542,"sku":"B098TQXKPP","price":66.48,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/ultra-1plus-front-packaging-3-quart.jpg?v=1785775873","url":"https:\/\/northtrailauto.ca\/products\/ultra-1plus-75w-90-full-synthetic-gear-oil-sae-75w-90-gl-4-3-quart-jug-low-temp-flow-high-load-protection","provider":"North Trail Auto","version":"1.0","type":"link"}