hey there everyone, we had gotten our tranny flushed about a week or two ago and then went downstate and experienced some hard upshifting a few times , since we have gotten back its done it repeaditly but not all the time, we've taken back to the garage that serviced it and they checked it somehow and drained and replaced the fluid again, the place weve taken it is very reputable and htey do good work. there not a small little garage though they are local, anyways we know that it was done right but why is it shifting hard jsut after the tranny being flushed? I have a GM/PONTIAC TSB for it saying that if the customer complains about hard upshifting that the Pressure Control Solenoid Valve Assembly needs to be replaced in this case, but id like to get all of your wonderful opinions first! Thanks in advance for any help! Also the trans checked out fin it the shops so called test?! whatever they did it didnt fix it though its not anyworse! Oh and the tech took the car for a ride and it didnt act up at all for him, he too it for about 7-9 minute drive at about 45/50 MPH... Why doesnt ever act up ehn the techs drive it?!?!?!
Anyways when he gave us the keys he said; "WOW that is a really nice car, real nice!"
Thanks again for any advance help! OH also i forgot to mention, i started doing this after we had driven thur a lot of water, couldn't see about 10 feet in front of you but had to get to the relatives place! ARGGGH! I HATE IT WHEN THINGS GO WRONG!

How does it react when you shift manually?
Race up in 2nd gear and shift 3rd, does it shift normally?
The flush is suspect and may have loosend some debris that has gotten hung up in a control assembly?

well they used a system to actually FLUSH the system not just drain and replace, well havent tried manushifting but will see what happens, will the garages that flush them usually back up there service if they screw something up? my mom who owns the car is really worried about it we just replaced the tranny in my brothers *-10, really dont know why it would break down though, hes only got the dinky little 4 banger! wow it puts out 120HP just kidding its a nice little truck! But 1200 bucks for transmission really scare you when your recently bought bonneville from the friendly neighbor starts acting up! actually we know thathe took good care of the car, well let me know what you think! thanks again sf/jr

Just wondering why you made the choice to have the transmission flushed,as opposed to just drained,filter changed,and refilled??Was the transmission doing anything unusual before you decided to flush it?

well thats what the garage that we went to and the transmission shop recommended! i didnt choosemy mom did! it was like 120 bucks. it only shift hard sometimeothertimes its smoothas glass!

the problem had stopped for now... knock on wood!!! Well we'll see what happens with it.. hopefully it has worked itself out, maybe just becuase we flushed it it irratated the trannys nooks and crannys (hey that rhymes!) Thanks though for the help.

How many miles on your car? Flushing is usually bad for our tranies unless they have low miles and its done on a regular basis.

Not entirely sure about this, but when these places do tranny flushes they are actually back flushing. In other words they force new fluid in against the normal flow paths. So all particulate on the top of the screen in theory should be flushed out. The fluid replenishment is about 80-90% as opposed to 50% with the traditional drop the pan & screen methods with tranny services.

The problem is after a lot of miles the clutch material becomes part of the fluid and the tranny continues to shift ok, but when its flushed all that clutch material is gone now and with new thin tranny fluid the tranny will begin to slip.

hmm so based on this, I can't tell - is flushing ever good? mine is 2000 ssei w/ 35000mi; it was off-lease vehicle so I doubt its ever been flushed/changed before... I'm getting a little 'catch' between 2nd and 3rd however I'm tempted to just leave it alone.. good idea?