Skip the auto shop - Our mechanics make house calls

Q: What happens if I unplug my transmission?

asked by on

If I unplug my transmission will it cause any issues beside horrible gas mileage? My transmission lost all the fluid yesterday, but I put more in as soon as that happened and it's still holding. I wasn't sure if it was the gasket. But I was told that the transmission has an overflow tub and that if it gets to warm the fluid will flow out. But if I unplug my transmission will my truck (4L60E) still shift right and I won't take a risk of screwing it up?

My car has 157896 miles.
My car has an automatic transmission.

A: Hello and thank you for contacting YourMech...

Hello and thank you for contacting YourMechanic. The 4L60E has electronic shift solenoids that shift the transmission in first, second, and fourth. If you unplug the harness to the transmission, your transmission will only have reverse and third gear.

In the event the transmission looses power to the solenoids, the transmission goes into limp mode which is third gear, for it is a mechanical gear only. Plus, the torque converter clutch will not work for it has an electronic solenoid that operates the circuit to apply the converter clutch.

My recommendations is to leave the plug on the transmission. The instant the plug is disconnected, the engine light will come on for the computer not communicating with the transmission. If your transmission is holding the fluid and is working fine, then it is good.

Check the transmission fluid with the engine running and at cold temperatures along with operating temperatures for proper oil level. If you need assistance with your transmission fluid, then seek out a professional, like one from YourMechanic who can help you with your vehicle.

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・Save up to 30%

Get a quote

What others are asking

Q: After multiple replacements, gas mileage is worse - 1997 Ford Aspire

The fuel economy will change depending on the whether the transmission is manual or automatic. According to fueleconomy.gov the manual transmission Ford Aspire is getting a combined 33mpg while the automatic get 26mpg. Ford's initial adverts were 34 mpg city...

Q: Why won't my truck run?

This could be a few different things. The first thing to do check is to check if the engine oil is not low and that there is oil pressure on the gauge. A loss of oil pressure will shut off...

Q: Tranny troubles

You need to have the transmission leak from the bell housing fixed. The fluid leaking is causing the transmission shift problem. The trouble code P2271 indicates that the O2 sensor after the converter shorted rich. This may happen if transmission...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...