Skip the auto shop - Our mechanics make house calls

Q: My Expedition vibrates a lot when stopped at a slope

asked by on

Every time I park my car on a slope (my garage driveway for example) it starts vibrating. Two days ago, I was turning right over a mild slope and suddenly I heard a huge sound coming out from the engine and the car almost came to a stop. But thereafter it ran fine, like nothing happened. The dealership recommended I replace the engine ($8000)!! They replaced selenoids, cam shaft and a cam phaser. It drives OK now but I'm not sure for how long. The other weird thing I noticed after replacing the selenoids was that may car stopped heating up. I drive it over two hours and when I get home the engine is kinda cool, isn't that odd? Why cars act up when on a slope? It doesn't seem like an electrical issue but maybe hydraulic. Can you help?

My car has 109000 miles.
My car has an automatic transmission.

Hello and thank you for your question. This symptom is not related to the engine but rather the transmission. If you drive the vehicle around and the engine runs just fine, then either the engine oil is low, causing the engine to be starved of oil on a slope, or the transmission bearings inside the transmission are worn out, causing the transmission to kick out of gear when at an angle. Usually the AODE transmissions, which is what your vehicle is equipped with, has an issue with the input shaft being out of alignment when it gets worn causing a mass leak in the torque converter to the input shaft. This makes the pump lose pressure and causes the clutch to release inside the transmission. I recommend hooking up a pressure tester to the transmission at the front of the transmission next to the oil cooler lines and monitor the pressure as you drive the vehicle. When going on a slope, if the pressure drops, then you need to remove the transmission and replace the input shaft seals. If you need assistance with your transmission, then seek out a professional technician from YourMechanic who can come to your home or office to diagnose your transmission problem and make the necessary repairs.

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: Need problem associated with EPC and ABS Lights fixed.

The EPC Light is for the electronic throttle body. You need to have a qualified technician check the codes on the computer to determine the problem. You may just have a loose vacuum hose connected to the intake. The ABS...

Q: Car wont start. The battery and starter have been tested are fine

This may be related to a faulty starter solenoid. The starter solenoid is located on the starter and has internal electrical contacts that transmit electricity to the starter. When this fails, it may cause a clicking sound and will not...

Q: Camshaft position sensor

Hello there, when the camshaft position sensor codes are seen with your 2008 BMW 328xi there is a variety of causes. The most common cause is a faulty camshaft sensor. If replacing the sensor does not help there are still...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...