Skip the auto shop - Our mechanics make house calls

Q: Car slams into gear after having transmission flushed

asked by on

I had my transmission fluid flushed and ever since then, when the car switches gears, it feels like it slams into gear (more than it used to before). It doesn't happen all the time, or between every gear shift, but it feels much more noticeable lately. Is it possible that the mechanic used a low grade fluid replacement? Or is it just me being more sensitive to it?

Sometimes, on older and/or high mileage transmissions, a fluid flush can be detrimental. The old fluid (which is full of friction material from the transmission clutches) is all that is holding the transmission together. However, this may not be the case with your vehicle. There is a TSB 08-07-30-002A for your Buick which states harsh shifting may be caused by problem with the valve body. Since the valve body is used to direct fluid flow to the transmission, it’s possible that your transmission flush exacerbated this problem.

Other potential cause for your symptoms include a low fluid level (if the shop didn’t add the correct amount), faulty accumulator, incorrect line pressure, and more. The list or potential causes is quite lengthy, so I suggest you have a trained professional inspect your vehicle firsthand to pinpoint your shifting problem.

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: Engine smoking from seals and overheating.

Hi there. Check the coolant level and see if its low. If it is low, then check the engine oil and see if the oil is black or like a milkshake. If the oil looks like a milkshake, then there...

Q: High beams come on whenever I use my right turn signal 2008 Pontiac Grand Prix

Hello - you have a wiring problem with the right front lights, most likely a bad ground for all the lights on the right, front corner of the car, but especially the right, front turn signal. I recommend an electrical...

Q: Car Starts fine, but shakes violently and loudly when shifted into any gear and wont move

Hi there. This type of issue is sometimes caused by motor mounts that are worn out or in some cases an exhaust leak. It's also possible that transmission mounts or CV joints are misaligned. The best way to correctly diagnose...

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...
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...
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...