Does changing transmission fluid hurt my transmission?

The answer is no.

But, does a transmission fluid exchange really need to be done?
Of course I would say yes. I work for a company that manufactures the BEST tools and equipment to perform a transmission service.

Here are the unbiased facts:

Your standard automatic transmission uses transmission fluid to activate hydraulic pistons, lubricates gear sets, and keep moving parts cool.

Still with me?

"Good. Now let's talk about what CAN hurt your transmission."

Heat hurts.

Heat is the culprit for most transmission failures. But you will always have heat in your transmission. In today’s transmissions, heat and transmission fluid are roommates… inconsiderate, incompatible roommates.

Over time and miles (at high temps), transmission fluid starts to wear out. As transmission fluid breaks down, it will cause the operating temp inside your transmission to rise even more.

Despite what you may hear from the “vehicles will last forever regardless of maintenance” fan group, every fluid has a breaking point. And when it hits that point, it’s no longer going to protect components.

In your engine, typical oil is expected to last 7,500 miles. In your transmission, fluid is breaking around 30,000 miles.

Neglect hurts even more.

Most of the horror stories you hear about transmission-related problems after a fluid change service are because the vehicle owner waited way too long to change the fluid. Which means the transmission most likely had hit breaking point years ago and the damage had already been done.

“But,” you may argue, “I’ve never had to do this with any car I’ve owned and I’ve never had a problem.”

To that I say, “You’re pretty lucky and your vehicle is living on borrowed time.” Also, “The next owner of your vehicle is probably paying for it now.”

Do yourself or your car’s future owner a favor, and stick to a solid maintenance regimen. Here’s some info on the BG Transmission Service.

By Tom Probus
BG Automotive Research Specialist, BG Proving Ground

Tom Probus is an ASE Master Technician and has been ASE Certified for more than 20 years. He joined the BG Proving Ground in 2015, where he helps invent new equipment that keeps BG at the top of the industry.

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