CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Transmission problem (?)

Hi…I have a 2007 Subaru Outback, automatic transmission with 28000 miles on the odometer. Recently, I noticed a jerking motion when I accelerate. This also happens when I slow down and speed up again. Is this a transmission problem? Do I have to get the transmission fluid changed? Thanks.

I suggest you check the transmission fluid. The owner’s manual will have instructions. It will also tell you how often to change the transmission fluid. Many here, myself included, recommend changing automatic transmission fluid every 30,000 miles, so you’re close.

At 28K miles you’re only 2k miles short of what should be your first transmission service anyway (drop of the pan and changing of the filter - no a “flush”). So you may as well just do it. Any good shop can do this - all the better if it is a transmission shop - but stay away from national chains. Go to a good, local, independent shop.

But a jerking kind of thing can also come from problems with how the engine is running - such as misfiring which can be caused by many different things.

Is the check engine light on?

No, the check engine light is not on.

Thanks for the suggestion.

I would suspect the engine before I would the transmission.

Since your transmission is about due for a change, yes you should change the fluid. However I would not expect it to fix the problem, it just needs to be done and maybe it might fix the problem, but I doubt it. It seems many people never change the fluid until there is a problem. Too bad, because by the time they change the fluid the damage is already done, then they blame the fluid change when it gets worse.

I would not rule out an engine problem. In fact I would look there first.

Your car is under full warranty. Take it to the dealer and let them diagnose and correct on Subaru’s dime.

People here have good suggestions on using independent, however that is past power train warranty (5yrs/60k).

I would spend a moment and check the level of transmission fluid.

The manual on Subaru more or less recommends transmission fluid replacement on Subaru’s every 30k miles. They also recommend diff fluids too.

Andrew makes an excellent point.

Since the vehicle still has coverage under the Powertrain Warranty, the OP should simply take it to the dealership and describe the symptoms. Even better would be if he/she can take a dealership mechanic along for a ride in order to demonstrate the problem.

Not only does the OP not need to give a diagnosis to the dealership’s service department, the service dept will actually not accept his/her diagnosis. Think about this:
If they proceed down a blind alley on the basis of a diagnosis that is given to them–Who pays for the labor (and possibly parts) involved in pursuing a bogus diagnosis? It would certainly not be either the dealership or the vehicle manufacturer.

Before going to the dealership, I would suggest that the OP open the booklet titled Subaru Maintenance and Warranty, see what needs to be done at the 3 yr/30k mile service, and also read the details on the various warranties that this car came with. I suspect that the OP is not familiar with either of these important details.