Skip the auto shop - Our mechanics make house calls

Q: is it safe to change Transmission Fluid. Hasn't been changed in a long time. Currently the Transmission is working fine; no slip

asked by on

Transmission is working fine. No slipping or noise. Car did not run for 3 years and fluid has not been changed for quite a while. A mechanic told me (without seeing the car) that it was unsafe to change the Transmission Fluid and it would cause immediate slipping due to new oil being thinner than old. Is this true? If I should NOT change the fluid, what should I do as preventative maintenance? (additives?)

My car has 213000 miles.
My car has an automatic transmission.

A: I agree with the other mechanic. If the flu...

I agree with the other mechanic. If the fluid looks dirty then this means the transmission was not serviced for a long time and if you service it then the new fluid will wash out all the clutch material that is being held together by the old fluid. You would be taking a big chance that the transmission will start slipping within a week after you service it.

A 75-point safety inspection is a good idea after long-term storage, and a qualified technician from YourMechanic can perform this for you at your home or office.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Shifting problem

This may be a sign of low transmission fluid or a faulty transmission control solenoid. As you know, automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car's computer activates a transmission...

Q: Ongoing coolant leaking issues - 2003 Grand Cherokee Jeep

Hey there. Odds are that the water pump is leaking. I would have a technician pressure test the cooling system. It will push the coolant out from wherever it is leaking to help find the issue. Rule of thumb, if...

Q: trouble finding compatible engine 3rzfe 2.7 coil type not cop

Hi there. Unfortunately, this is a question better served to ask an engine replacement shop, since our mobile mechanics don't offer engine replacement services. You might also want to search for online forums for Toyota owners and fabricators to receive...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.