Thread: pcs ... epc swap on 4T65E-HD

has anyone ever done a do-it-yourself epc and or pcs swap on the HD...if so how much work has to be put into it?.also if i keep driving my car with bad pcs will it screw the tranny up completely?

Replacing it isnt terrible but does require some serious ambition to tackle! You have to put a jack under the trans OR have an engine support craddle from the top, then another jack to put under the craddle. You can jack up the drivers side of the car pretty high and leave the passanger side on the ground which helps keep the mess down and also when digging into the valve body keeps things from wanting to fall out so easy. You wont need to remove the axle just to change the solenoid as long as the side cover gasket is in good shape. If the rubber is torn from the metal-it is a molded gasket- it needs replaced or will likely leak. NEVER use air or impact tools on the side cover when reinstalling as they can crack on the bottom bolt holes! Anyways back to removal, you will have to likely slighly loosen the passanger side craddle bolts and remove the drivers side craddle bolts and is also a good idea to unbolt the steering rack from the craddle so you dont pull the shaft apart in the column. You will have to remove the trans mount from the craddle and then you can lower the craddle down near as far as it will go. You may also need to remove the engine upper dogbone mounts to allow more freedom to lower the trans down. At this point you should be able to remove the side cover and push it over enough to replace the pcs.

As far as not doing anything like I mentioned it will be more of an annoyance than anything else but for a long period of time is going to work the pump harder and potentially cause excessive pump and or shaft wear.

When code 1811 pops up a whining noise is generally heard as the pump is now working at max output. When you reset the code or restart the car and it goes away then replacing the solenoid should addres this.

Originally Posted by gtpinsc

one other thing that has been happening the past few days is the TRAC OFF light comes on along with ABS light.when this happens i lose cruise control.lights will usually go off after a restart. is this a seperate problem or the problem i have getting worse.sorry i try to put all info in original threads when i post, but my mind goes out of order sometimes.

Bad wheel speed sensor or bad harness to one of your wheel speed sensors.

Originally Posted by gtpinsc

but it only does it when trans starts acting up.im wondering if its tied into pcs problem.

But they have nothing to do with each other and aren't even tied together anywhere but the PCM. Even then it's still a stretch. The TCS/ABS system is controlled by the EBCM, which talks to the PCM over the OBD2 bus, which controls the transmission.

I think if you set the expected shift time extremely low, then it will cause that problem. See, it's possible (I think) to set it so low the transmission can never reach it. Then, the PCM thinks something is wrong because the transmission isn't performing as it expects it too (taking too long to shift, in its opinion) and sets P1811.

But, this is speculation and Trannyman would probably know better.