Transmission Shifting Hard (Fluid related?)

[2002ls1z]

I've got a 2001 Buick Century for my daily driver with 90k on it. The transmission has never given me any problems. Tonight it was upshifting hard, kinda like it had a shift kit. It wasn't slipping though. So I checked the fluid and noticed it did seem low (it's really hard to tell). So, I added some Lucas Transmission Fix to it and it shifts fine again. I really don't know a lot about automatics transmissions. The fluid in there looked pink and didn't smell burnt. Would low trans fluid cause it to shift rough or is the Lucas stuff hiding a big transmission problem? Looks like i'm going to get a transmission flush tomorrow just to be safe. Thoughts?

[slick]

Pink/red fluid is fine. The fluid is probably original, so a flush won't hurt. Be sure to change out the filter as well.

 

As a rule of thumb, I generally run a little over the full mark. They don't leak, however, if you happen to be making a turn quite quick, and the fluid is sloshing around, the pump may not pick up the fluid. In fact, lots of Auto-x'ers do this.

 

Yeah, get that Lucas crap out. Additives are always a no-no.

[jeremy]

I've heard nothing but bad things about the Lucas additive

[oldscsc]

Low fluid level can cause it to shift hard, yes.

[slick]

Oh, and be sure to post LOTS of pictures of your other car in the Other Cars section!

[ManicMechanic]

Red fluid - good

 

Pink fluid - bad

 

If it is a bright pink, that usually means there's coolant mixing in with it.

[2002ls1z]

Oh, and be sure to post LOTS of pictures of your other car in the Other Cars section!

 

I have a few, i'll post them

 

 

[88red4cyl]

Pink/red fluid is fine. The fluid is probably original, so a flush won't hurt.

 

I've always heard that flushing is bad???

[Night Fury]

Pink/red fluid is fine. The fluid is probably original, so a flush won't hurt.

 

I've always heard that flushing is bad???

 

I hear a new thread coming on!

[slick]

Pink/red fluid is fine. The fluid is probably original, so a flush won't hurt.

 

I've always heard that flushing is bad???

 

With that low of miles, shouldn't hurt it.

 

But, I know what you are referencing to. Seems like a hit or miss really.

[Brian P]

my sister's '02 Grand Prix with an identical powertrain to your Century had a similar problem. It was more of a 1-2 slow slip-shift, then harsh grab to 2nd gear. I did a pan drop, changed the fluid and filter and it never happened again.

[Regal_GS_1989]

Is the check engine light on?

 

I know that the pressure control solenoid sometimes will go bad and can cause the harsh shifting. IIRC, the code that it throws is something along the lines of "Slow shift adapt" or Long shift adapt.

[2002ls1z]

Is the check engine light on?

 

I know that the pressure control solenoid sometimes will go bad and can cause the harsh shifting. IIRC, the code that it throws is something along the lines of "Slow shift adapt" or Long shift adapt.

 

Nope. I drove the car 25 miles today and had no problems. I'm going to have the fluid and filter changed tomorrow though.

[Andrew]

make sure they actually change out the filter. i had a shop tell me they dont even do that anymore, they just flush the system out. i was like

[MonteCarloDude]

make sure they actually change out the filter. i had a shop tell me they dont even do that anymore, they just flush the system out. i was like

That's crazy!

[BIGBULS]

Is the check engine light on?

 

I know that the pressure control solenoid sometimes will go bad and can cause the harsh shifting. IIRC, the code that it throws is something along the lines of "Slow shift adapt" or Long shift adapt.

 

I hear a winner..............

 

And the DTC is P1811, "max adapt and long shift".........PC solenoid is a VERY common thing on 65-E's and is only about a $60 part last time I checked, although it IS a fair bit of work to do it. Oh..........and you'll need a sidecover gasket and it's a VERY good idea to change out the left axle seal at this time too (they all leak sooner or later).

 

Be aware the PC solenoid CAN fail without setting a DTC too............

[jman093]

make sure they actually change out the filter. i had a shop tell me they dont even do that anymore, they just flush the system out. i was like

 

Well it depends on what you're having done. Dropping the tranny pan and changing the filter is not a "flush" and doing this only changes about half the fluid as the torque converter is holding a few quarts that don't come out when you take off the pan. So a "flush" is done with a machine that you hook up the the tranny lines and it pumps new fluid into the tranny as the car (running) is pumping it out. A flush exchanges all the fluid, but obviously you've still got your old filter. Quick-lubes places and even some shops will only offer flushing since it's a lot quicker and they can still charge a lot.

 

I work at a dealer and we'll do either depending on what it needs more.

[2002ls1z]

Is the check engine light on?

 

I know that the pressure control solenoid sometimes will go bad and can cause the harsh shifting. IIRC, the code that it throws is something along the lines of "Slow shift adapt" or Long shift adapt.

 

I hear a winner..............

 

And the DTC is P1811, "max adapt and long shift".........PC solenoid is a VERY common thing on 65-E's and is only about a $60 part last time I checked, although it IS a fair bit of work to do it. Oh..........and you'll need a sidecover gasket and it's a VERY good idea to change out the left axle seal at this time too (they all leak sooner or later).

 

Be aware the PC solenoid CAN fail without setting a DTC too............

 

I think this may be the issue. It started shifting hard again today, but no code. I turned the car off for 5 min and no problem. What do you think labor is going to run me? How many hours will this job take?

[1990lumina]

make sure they actually change out the filter. i had a shop tell me they dont even do that anymore, they just flush the system out. i was like

 

Most import cars don't even have filters.

[Regal_GS_1989]

Is the check engine light on?

 

I know that the pressure control solenoid sometimes will go bad and can cause the harsh shifting. IIRC, the code that it throws is something along the lines of "Slow shift adapt" or Long shift adapt.

 

I hear a winner..............

 

And the DTC is P1811, "max adapt and long shift".........PC solenoid is a VERY common thing on 65-E's and is only about a $60 part last time I checked, although it IS a fair bit of work to do it. Oh..........and you'll need a sidecover gasket and it's a VERY good idea to change out the left axle seal at this time too (they all leak sooner or later).

 

Be aware the PC solenoid CAN fail without setting a DTC too............

 

I think this may be the issue. It started shifting hard again today, but no code. I turned the car off for 5 min and no problem. What do you think labor is going to run me? How many hours will this job take?

Up here, you would probably be looking around 600 - 700 dollars. I've only experienced this repair done on a Venture, and the cost to replace both the TCC and the PCS solenoid was right around 700$. I'd assume that a W would be about the same cost. Best bet is to take it and get it checked out by a reputable trans shop. Most shops should be able to tell you over the phone what the average cost is for your type of vehicle, as it is a fairly common repair.

 

 

[mcbfarm]

If the Lucas additive appears ok, it's ok. People add stuff to a failing AT and think the additive caused it... but the level is probably your real problem. Get it right and check it often. And Change it -- as close to every 15,000 miles as you can. Like brushing teeth, only change the fluid on ATs you want to keep SOme additives can change the feel of shifting; if you notice this and it's not for the good, drain it. If it works, it works, don't panic and drain new fluid just because you've added Lucas.