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Transmission shifts hard sometimes

130,000miles transmission shifts hard in every gear sometimes other times it is completely fine. thought about servicing it with new fluid, filter, flush but have heard that this could cause problems since so many miles

What year is your Buick?? Which engine?? Has the transmission ever been serviced?? At 130k miles you should have had the pan dropped, filter changed 4 times already (Every 25-30k miles) Has this been done??


Look at this post: since you probably have the same transmission.

The short story is that you need to go to your best local, independent transmission shop to have it checked out. You can keep your fingers crossed if you want, but my guess is that your next question is “should I put a new transmission in this thing or just buy a different car.”

thought about servicing it with new fluid, filter, flush but have heard that this could cause problems since so many miles

Yea, those are the people who don't get around to changing the fluid and cleaning the filter until AFTER it starts having problems.  It is not the fluid change that cause the problems, rather it is waiting too long to change the fluid that is the cause of the problem.  

There is no way of knowing now what will happen, but I would consider change the fluid and cleaning the filter and hoping that I am lucky.

it is a 2004 with a 3.4 V6 and no the transmission has never been serviced.

but it can go 6 months or more and be fine but then it always seems like winter when it messes up

Have you at least checked the transmission fluid?

Either way the story doesn’t change - take it to your best local, independent transmission shop. They can scan it and run diagnostics.

If it has never been serviced then expect no miracles. The thing is probably mostly gone. But if it were mine, depending on what the transmission shop says, I’d have the pan dropped, change the filter and then do a full fluid exchange - not a “flush” - just a complete fluid exchange. If it fails soon after that it won’t be because of the service. It will largely be because you went 130K miles without ever having it serviced. Consider yourself lucky. A lot of those transmission don’t make the 100K mark.

ok will do i will report back after the service. thanks for the help. btw i have checked the fluid it is fine and clean. do u know what the going rate is for a good transmission?

Have you scanned the computer for codes??


no. the service engine light does not come on. or will it still spit out codes even though?

Some codes will turn on the light. Other codes can be set, but not turn on the light. For those that don’t turn on the light a generic OBD II code reader will not read them - it will just indicate no codes. A good local transmission shop will be able to pull codes not matter what kind.

Yes it can have codes w/o the light on. Take it to a local auto parts store who reads codes for free and have them scan it. Post back with any code/s and we can go from there.


ok great. i will post asap

OK well I went to the dealer and they serviced the transmission I(changed the fluid and filter no flush) still does the same thing went to the auto parts store and had them run the diagnostic on it and all it said was that the “coolant temp is always low”

You need to clarify.

Did the dealer scan it for codes or what? Result?

If the auto parts store pulled a code regarding coolant temp that is important. If your coolant temp is remaining low this suggests a stuck open thermostat. This will cause all kinds of problems (no heat, very poor gas mileage, and yes - may even create transmission issues). It also suggests that your check engine light is on -? Or not. In any case, what was the exact code they pulled out? (e.g. “P1234”).

OK to clarify the auto parts store did the scan PO128. I went to the dealer they just changed the transmission fluid and filter no flush.

the code said that to check coolant level or it could be a defective thermostat or engine coolant temperature sensor

and yes the gas mileage is poor 17mpg at best used to get around 23-24mpg

and no the check engine light is NOT on.

What my troubleshooters show for this code is:
Thermostat sticking open or slow to open, or low coolant level. Those are the most common causes. Other things found are a missing restriction orfice for the radiator surge tank causing excessive coolant flow to surge tank. Techs have been finding missing restriction orfices in vehicles which have had radiator replacements. Has your radiator ever been replaced??


No radiator has never been replaced