Impala Forums banner

Transmission Shifting

29K views 12 replies 12 participants last post by  zerialz 
#1 ·
I'm still having a hard shift after the car warms up, 20 miles or so. Repair shop says rebuild req. What about ( pressure control solenoids). I need to know if the big bucks are required. I have a 2000 3.8L Impala.
 
#2 ·
get it scanned and see if the p1811 code comes up. if so, its your pressure control solenoid.
tripleedgeperformance said:
Intermittant Harsh Shifting / Pump whining, Possible Code P1811:This is perhaps one of the most common problems with this transmission. It has been a problem since the release in 1997 and can happen for no reason at all even with clean fluid and very low mileage. The EPC solenoid is probably bad and again is very common to happen. The EPC solenoid controls line pressure and has a spool valve which oscillates back and forth to regulate transmission line pressure based on commanded pcm signals dependant on lots of various inputs of the vehicle. The spool valve in the solenoid will bind up and cause loss of pressure control from the pcm. The pcm constantly monitors shift timing in milliseconds and if this is not within programmed parameters after a few shift cycles the pcm triggers trouble code P1811 which is Max Adapt / Long Shift. This code will not set the SES light but will dissable all adaptive shifts and will max out line pressure in the transmission which causes the harsh shifts and can also cause the transmission pump to whine because it is supplying fluid at a high rate and pressure and puts more stress on it thus creating the whine. Generally shutting off the car will make this condition go away until you drive a few more miles or the vehicle warms up and the harsh shifting will return. Replacing the EPC solenoid will most likely correct this condition and again is probably the most common problem found in any year of this trans. I will also add that a worn out transmission can cause this. If the fluid looks bad, dark, and smells burnt or lots of fine dark sludgde or a dark film of material is in the bottom of the pan then there is probably internal damage. Once clutches become burnt and have excessive wear shift timing will be greatly extended and the pcm will fall outside of its set parameters and code P1811 will turn on, again commanding higher line pressure and harsh shifts but an overhaul in this instance is the only proper fix.


http://www.tripleedgeperformance.com/4T65E_Transmission_Info.html
 
#5 ·
ok so has anyone replaced this pressure control solenoid on there own without taking it to a shop if so how difficult is it can it be done as a weekend project? any additional info would be helpfull as i am also having the rough shifts in my 05 w/3.4L just not all the time its very sporatic i do alot of the simpler fixes/projects but this might be outside my range what do you think
 
#10 · (Edited)
ok so has anyone replaced this pressure control solenoid on there own without taking it to a shop if so how difficult is it can it be done as a weekend project? any additional info would be helpfull as i am also having the rough shifts in my 05 w/3.4L just not all the time its very sporatic i do alot of the simpler fixes/projects but this might be outside my range what do you think

This is not hard you have to remove side pan on driver side of trans but support engine with engine support to suspend engine because you have to disconnect lower ball joints sway bar links and frame to tilt trans on driver side to remove screws in pan(note disconnect battery power)trans pump must be removed to get to the pcs so purchase gaskets to re-install while you have this off you'll be safe to just put in trans shift solenoid and torque converter solenoid since you r in their you wont regret it it make sense.
 
#7 ·
Here is the persons # i have been dealing with 1-866-790-5600 ext 11310. Tell her your problem, she wants to hear all about it. It is a GM customer service line. The problem is common with these tranaxles from 97 to current. They get hot and shift hard, code P1811, it is suppose to be the PCS.
 
#9 ·
Seriously guys, this has been discussed before.

Yes, you can replace it yourself. With a complete set of tools and jackstands you can knock it out in about ten hours. Either by pulling the engine and trans through the top, or dropping the cradle to get access to the side cover. Either way it's a pain.

You can call GM Customer service to complain, but considering that this has been an ongoing issue for 13 years now, it's pretty much consensus that they aren't going to address the issue.

You can get it repaired at a local shop for $300-400 bucks. If they try to charge you more, find another shop. If they want to condemn the trans, look at a rebuild from Triple Edge Performance. You can get a good build for about $2000.
 
#11 ·
The inner solenoid in the transmission goes bad. It's a known problem in Impala's. My car has 223,000 miles and it's having the same problem. It's between $2000-$4000 to get it fixed because they have to tear apart your transmission... And it may not be fixable once they get in there to look at it.Your best bet is to do a transmission swap.
 
#13 ·
And bad info given on that last part :(
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top