What Type of Differential Do I Have and What Type of Vehicle Gear Lube Should I Use?

If you’ve read the latest magazine ad, or maybe look for a new-to-you vehicle, one of the selling points may be the differential.  There are three main types of differentials.  If you’re not sure which is the best for you and your driving, we’ll break each down.  We’ll also explain how to find the correct gear lube for your vehicle since there are multiple types available.

Type #1 – The open (or standard) differential

The open differential is the most common differential available. They were very common in early trucks, but have stayed in use through the vehicles being made today. The architecture of the open differential is a carrier holding a ring gear, a spider, and side gears. They are one cost-effective option for most vehicles, and most manufacturers use them for predictable handling, low maintenance, and tire longevity. One of their downfalls is their inability to drive both wheels in all situations. The open differential directs power to the wheel with the least resistance. That can cause one wheel to spin if it has minimal traction and the other does nothing. If you’ve ever heard the term ‘one-wheel peel’, it describes one wheel spinning while the other is stationary.

EasyPack SevereGear Vehicle Gear Lube

Type #2 – The limited-slip differential

The limited-slip differential attempts to solve the problem of the open differential: driving both wheels at once. The limited-slip differential directs equal power to both wheels.  It uses a collection of clutches to maintain a balance between both wheels. Clutches are made to slip with the tire’s traction and turning.  As your vehicle corners, the inside wheel turns slower than the outside wheel. The limited-slip differential allows both wheels to turn under power.  The clutches allow a minimal amount of slip as the wheels need to rotate at a slightly different speed.

One of the unwanted traits of the limited-slip differential is that the clutches eventually wear out. When this occurs the differential loses the ability to drive both wheels equally. Normal wear and tear happens over time, however the differential fluid can cause additional wear if the incorrect fluid is used.  The wrong fluid can have poor frictional properties that cause irregular clutch engagement and disengagement. When that occurs, it’s known as ‘chattering’, and it can be frustrating to deal with.

AMSOIL Vehicle Gear Lube Lubricant

Type #3 – The locking differential

The locking type of differential is similar to the limited-slip differential, but it features a mechanical locking feature that directly connects the axles instead of using spring pressure and clutches to transmit power to each wheel. By using the mechanical connection, the wheels on either side turn at the same speed regardless of turning or straight-line travel. The mechanical connection can occur manually or automatically depending on the type of differential.

What Vehicle Gear Lube Oil Does My Differential Need?

If you review the different options for gear oil, it may be confusing of which viscosity to buy and any additives to look for. The first place to check should be an owner’s manual or a service manual for your vehicle. It should list the viscosity and quantity needed to service your differential. If you don’t have a manual for your vehicle, you can always use the AMSOIL Auto & Light Truck Lookup Guide to find the right gear oil viscosity and quantity. AMSOIL does have many variations of gear oil, but they don’t cover an unlimited amount of differentials. For unique cases that require an additional additive, AMSOIL Slip Lock is available to accommodate your unique situation.

No matter what viscosity your differential requires, AMSOIL will have you covered. Their award-winning synthetic options are available in a quart sized Easy-Pack that reduces waste and mess during installation. Today’s synthetic gear oils reduce thermal runaway and prevent corrosion. If you need help with determining a complete maintenance plan for your vehicle, your local AMSOIL dealer at Buy Great Oil is here to help with a complete package of products and hints to make the job easier and more cost effective.

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