Egr Tube Replacement Tips And Tricks

[Crusty1]

Just replaced a cracked EGR tube on my son's 96 LS400. I've read all that I can find on the web and found a few tips that may make it easier for any DIYer attempting this himself.

First off, for those of you who were able to replace an EGR tube without removing the right side cat I bow at your feet saying "I'm not worthy" repeatedly. I have idea how you pull this off because I couldn't even see the top 2 bolts without taking off the cat. And yes, the bolts on the cat were completely frozen. I stripped 2 of the three upper nuts attempting to get it off. After soaking in PB Blaster for 48hours and then hitting it with a propane torch with no luck, I pulled out the big gun: "CRC Freeze Off!." If you haven't ever uesd this stuff, it's simply amazing. After shooting the nuts/bolts with Freeze Off, 90 seconds later, "BAM!" they're off. So if you're afraid to remove the right side cat because the bolts are frozen, now you know. However, a caution: Freeze off has a flash point of 104 degrees. So be careful. And the way to get the stripped bolts/nuts off is with your Craftsman stripped bolt/screw remover set. Works like a dream even when the nut is stripped round.

After getting off the cat, the two lower nuts are cake to get off; top two bolts, not so easy. To get them off, working from the bottom, I used a long extension and swivel socket with painters tape wrapped around the swivel joint. Painter's tape allows you to position the angle of the socket so it doesn't flop around while you're trying to get it on the head of the bolts. When I got the bottom two nuts off the bottom half of the EGR tube fell off and hit me in the face. No wonder it sounded so crappy!

Once it was off putting it back on was another challenge. Feeding the tube up from the bottom it's pretty easy to get the flange over the bolts and then just screw the nuts on. No big deal. But getting the proper orientation for the upper two bolts which are inserted into threaded holes is another story because you can't really see much of the treads looking up from the bottom.

Note: I've read that a lot of guys work from the top. I couldn't get my hand between the firewall and all the tubes running around the back of the engine to thread the first bolt, the top one, to get the orientation right. Obviously, if you get these bolts cross threaded, or muck up the threaded holes, you're SOL. So I got a little creative. After unbolting the brace that runs along the bottom attached to the exhaust, I jacked the transmission up about 2 inches. I know, living dangerously. But I thought there'd be enough "slack" in the motor and tranny mounts to allow for this after I made sure I wasn't going to pinch any fuel, cooler, or AC lines in the process. Once I felt resistance, I stopped. And I used a big wood block under the tranny pan to prevent damage. Once jacked up the engine had moved far enough away from the firewall that I had enough room to squeeze my hand down the back side of the fire wall to get my hand in position to work. I couldn't hold the bolt in my hand as I worked it down the back of the firewall so I attached a piece of thread to the bolt and lowerd it down into place and then slid my hand down afterwards. Still tight, but doable. Once I could insert the bolt into the flange of the EGR tube I could safely begin to feel the proper orientation to thread the bolt into the threaded hole and position the tube at the same time as well. Once the top bolt was in I had the proper orientation/alingment to insert the bottom bolt in from the underside of the vehicle. I used the same painter tape trick on the swivel but also wrapped painter's tape around the socket leaving about 1/16" protruding about the edge of the socket. I used this to press down on the underside of the bolt once inserted in the socket so that I wouldn't keep losing it when it boinked on something and fell out for the umpteenth time.

I Don't honestly know if any of these ramblings will actually help anyone or not. But it sure helped me get this job done myself without having to take it to the dealer ($1100 quote) or drop the tranny. I've already R&R 2 trannies this year so I've met my quota.

But WOW does this car run smoother and quieter now....and doesn't sound like a '73 LTD like someone mentioned.