What is a CVT Transmission? Can we prevent their problems?

“CVT” stands for continuously variable transmission. Which means saying “CVT transmission” is redundant, like saying “PIN number” instead of just “PIN”. A CVT uses a pair of variable-diameter pulleys and a belt or chain to provide unlimited gear ratios.

To illustrate, think of a traditional automatic or manual transmission. They’re built with a defined number of gears, for example first through sixth (plus reverse, of course). When you’re driving, you can only select one of those gears, and no more. You typically feel a slight surge with each gear change.

CVTs, however, offer unlimited gear ratios. Take a look at the image. You can see the metal belt connecting the two pulleys. Depending on engine speed and load, the computer automatically varies the pulley sizes to ensure the optimal gear ratio for the driving conditions.

CVT belt system cutaway

CVTs use variable-diameter pulleys to create unlimited gear ratios.

Minimum input for maximum output

What good does that do?

Imagine pedaling a bike. As you approach a steep hill, you adjust the shifters so a smaller chainring attached to the pedals is driving a larger sprocket on the rear wheel. This reduces the effort required to move the bike.

When you reach a stretch of flat road, you adjust the gear ratio again so you’re using a larger chainring and smaller sprocket until you find the perfect balance between energy expended and bicycle speed.

The same principle applies with a CVT, except the computer does all the thinking for you. When starting from a dead stop, it varies the pulley diameters (smaller drive pulley and larger driven pulley) so the engine can move the car as efficiently as possible. As you accelerate, it continuously varies the pulley sizes to keep the engine in its “sweet spot,” which results in improved fuel economy. Plus, you never feel the gear engagements because, in effect, there aren’t any.

CVT Transmissions Gaining in popularity, but there are negatives

These benefits are why many car makers, including Nissan, Honda and Toyota are introducing more vehicles with CVTs.

There are drawbacks, however, including the “rubber band effect” (you rev the engine, yet it takes a moment for vehicle speed to catch up) and lack of driver involvement (zero fun). In addition, most CVT transmissions relatively diminutive parts can’t handle the power and torque of the truck or SUV you use to tow your boat or camper. Although the 2017 Nissan Pathfinder comes with a CVT as standard fare, so CVTs may eventually work their way into the larger vehicles Americans love.

The main issue to understanding a CVT is to study the make-up of the belts and internal bands. AMSOIL’s fluids are adjusted and trialed to solve the overheating and wear issues of these belts.

Slip into something special

One look at the guts of a CVT and you can’t help but wonder how the belt doesn’t just slip wildly over the pulleys. Believe it or not, the transmission fluid plays a major role in ensuring the belt or chain remains in contact with the pulleys without slipping.

That’s why CVT transmissions require specialized transmissions fluids, and not the traditional automatic or manual transmission fluid you probably have in your garage. CVT fluids must be formulated with the correct frictional requirements to guard against slipping. Using the wrong fluid will reduce performance and potentially wreck your transmission.

Wear protection also important to extend assumed life of the CVT Transmission

Solid wear protection is also vital to maximizing CVT performance and life. That’s why we designed AMSOIL Synthetic CVT Fluid to fight wear and help extend transmission life. To demonstrate, we pitted AMSOIL Synthetic CVT Fluid against Nissan NS-2 CVT Fluid in a field trial. After 100,000 miles, the belt lubricated with AMSOIL Synthetic CVT Fluid demonstrated minimal wear, as you can see in the images. This helps you get the best performance and most life out of your CVT.

AMSOIL Synthetic CVT Fluid protected against wear.

 

The belt lubricated with Nissan NS-2 CVT Fluid demonstrated increased wear.

While driving purists may initially scoff at the notion of a transmission that requires no driver input, many eventually warm up to CVTs’ increased gas mileage and smooth operability.

If you’re one of them, make sure you protect it with a good CVT fluid.

Editor note – we had a local customer who is a tire dealer for Yokohama. His son drove the Nissan car just after switching the fluid. His dad said he had a huge grin on his face!! The difference was noticeable!

 

Winter Driving Tips

December 6, 2021 Maintenance

Winter Driving Tips John Baker|Oct 08, 2020 7:20 AM With the worst of winter right around the corner, now is a good time to get your vehicle prepared for potentially hazardous roads. Here are a few winter driving tips, along with ideas to prepare your vehicle for winter. Prepare you car for winter Battery check – […]

A CLOSER LOOK AT DIFFERENTIAL COVERS A new differential cover can help provide increased performance. Although they’re not always top-of-mind for enthusiasts, differential covers play an important role in the performance of pickup truck differentials. In addition to providing access for changing gear lube, differential covers help dissipate heat that can damage differentials, and they […]

NEW MOTOR OIL SPECIFICATIONS NOW IN EFFECT The automotive industry’s latest specifications, ILSAC GF-6 and API SP are now effective. AMSOIL is ahead of the game. Original equipment manufacturers (OEMs) are under pressure to improve fuel economy and reduce emissions. As a result, most new engines today use some combination of turbochargers, direct-fuel injection and variable valve timing to deliver better fuel economy and increase […]

How to Adjust Snowmobile Belt Deflection John Baker|Feb 02, 2021 8:11 AM Setting the proper snowmobile belt deflection is one of the easiest things you can do to ensure your sled performs at its peak level. In this video, we show you how it’s done.   Time needed: 20 minutes. How to adjust snowmobile belt […]

Dealer Robert Lolato of Orleans, Ontario, Canada

DEALER: ‘EVERYTHING RUNS BETTER, LASTS LONGER’ Dealer Robert Lolato of Orleans, Ontario, Canada has been a believer in AMSOIL products for more than 20 years. He started using AMSOIL products in 1985. “I can tell you firsthand that my experience with AMSOIL products has been phenomenal,” he said. “Everything runs better and lasts longer. That’s […]

Watch How These Snowmobile Oils Handle -40º John Baker|Jan 27, 2017 9:33 AM   Like the engine in your car or truck, the engines that power your two-stroke snowmobile are growing more sophisticated with each passing year. The same demands driving changes in the automotive market are influencing two-stoke engines as well – the government […]