So i was like many of you having rear bag suspension issues. Got on the site, looked, read, and learned. Thanks for all the advise by the way. My rear compressor would sometimes come on and sometimes not. It was a hassle. I ruled out it wasn't the sensors because i never had height irregularity between the sides and i originally ruled out it wasn't a bag leak because it would stay full over night most nights. I sprayed the lines and didt see any leaks. I had just replaced the transmission and so i couldn't stomach another 2G repair so of the three options, OEM($1300), used OEM(800), or generic (258) i went with the generic. Taking the old one out was that bad. Def go ahead and lower the spare first because you need to be able to stick your head into the hole where the spare was to see the air connections between the lines and the compressor. Obviously remove the plastic cover, remove 2 of the three bolts that hold the compressor. the third isn't accessible. loosen, but don't remover the black circular air duct connected to the compressor and then you will be able to remove compressor. remove rubber fittings, detach air supply lines from the suspension to compressor and its out. install in reverse order. Everything went back together well except for the last power line to attach in the end. I had to take plyers to it in order to fully seat. Turn vehicle back on and it didn't work. Thats right, no go, bummer. Took to dealer and prepared to bend over. I prepared myself for the worst and to only repair what was broker, dealers love to fix the just in case and while we are hear bull**** stuff as well. Dealer came back, and said that right bag leaked, compressor i removed they thought was shot. they suggested replacing both bags and they also said the compressor / vehicle did a hard reset on the old compressor turn the pathway off all together and that is why the new one wasn't working. Glory days!! walked out having dealer replaced only leaking bag- 290-, diagnostic-130- and a few other unrelated things. all in all i save myself 1500 by buying and installing compressor myself. I love my truck again!! hopefully no new issues for a while.