Best Transmission Additives: Restore Your Transmission’s Health for Smoother Performance

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Has your car’s transmission suddenly started acting up? Is it shuddering while you’re on the road, or struggling with harsh gear changes? It’s time to check out what’s happening under the hood. Problems like these could mean your transmission is in need of repairs. But it could also indicate an issue with your transmission fluid. While you might not think about your car’s transmission fluid very frequently, it’s a small part of your vehicle’s most critical system.

Unfortunately, we're all guilty of letting the health of transmission fluid slip our minds and failing to change it or top it off when necessary. When this happens, issues can persist or arise long before service intervals come up. While there's certainly no replacement for a proper fix, transmission additives can help you're transmission stay in the fight until you're ready to take it to the shop. Thankfully, there's no shortage of options to chose from. We have the best transmission additives available right here, along with a guide to help you find the right fit for your vehicle.

To select these products, we weighed how price, benefits, and application came together for each and denoted as necessary. If a transmission additive has few benefits but commands a reasonable price, it's not necessarily a bad product. On the other hand, if a product is on the more expensive side and also has few benefits (especially in user review form), then that's not as ideal.

We also cover a wide variety of transmission additives, meaning ones that could either work in conventional, torque-converter automatic transmissions, manual transmissions, and CVTs (or all of the above). Then, whether the additive plays nice with conventional petroleum-based or synthetic transmission fluid.

For more info on our methodology, check this out.

Noticeable benefits include smoother shifts, less noise, and reduction in shuddering

Good price

One small bottle is all it takes for most transmissions

Does not work with CVT transmissions

Does not work with high-mileage and older vehicles

Prolong Super Lubricants PSL15000