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Removing your Cats

Old 01-01-2008, 06:33 PM
Thread Starter
Join Date: Dec 2004
Location: Seattle, WA
Posts: 8,980
Default Removing your Cats

Written By: mustang196718

Alright guys, here’s what I did to remove the front cats. First things first, I’ll give you a brief overview of what removing the front cats entails. The car is going to either need to be on a lift or up on jack stands to get this done properly. The front wheels need to come off, along with the brake calipers, rotors, upper control arms, the rest of the exhaust from the upper exhaust pipes back, CV shafts, and the CV shaft heat shields before you’ll actually be able to remove the upper exhaust pipes where the cats are. It sounds like a lot of work, but it’s really not too bad after you get into it. And I of course have to include my little disclaimer stating that if you in some way break your car, I am in now way responsible yada yada yada…

1. Jack up the car and remove the front wheels first using a 17mm socket.

2. After you have the front wheels off, pop the center caps out and put the wheels back on. Get them torqued on there properly and set the car back on the ground.

3. Through the center cap hole you should be able to see the bolt that holds the CV shaft to the hub assembly. There were a couple different ones, so yours could either be a regular bolt, or in my case, a 17mm allen. In either case, you’re going to probably need a ½” drive socket wrench with a nice pipe or something else to give you some extra leverage because they’re torqued on there pretty good. Just loosen these so that they’re not tight.

4. Now disconnect the battery. You are now going to need to unplug the O2 sensors. You may have to take off some of the engine plastics to get to these. The plugs are black and are right up against the firewall in little plastic clips. The passenger side one will be grouped with a green and a brown one, whereas the driver’s side will be grouped with a smaller grey one. You only need to unplug the BLACK ones. Also, make sure that there aren’t any zip ties holding the wires so that when you lower the exhaust, it’s not going to get hung up by the O2 wires being tied up.

5. Lift the car back up, or put up on jack stands, whichever your case may be, and remove the wheels once again.

6. This time you can go ahead and remove the brake calipers via the two large bolts on the back of the caliper assembly. They should be a 5/8” or something to that extent. Go ahead and take these out and pull the brake caliper off the rotor. Be sure to wire up the caliper somewhere so it’s not hanging by the brake line. Also make sure that you take out the ABS sensor, it should be a little allen screw, just be careful not to break the sensor.

7. With the brake calipers off the rotors and wired up, go ahead and knock the rotors off the hub assembly. Nothing is holding them on at this point except for the center protrusion of the hub, so all you have to do is tap it with a rubber mallet and they should pop right off (or in my case they’ll be rusted on and you’ll have to use a block of wood and a big f****** hammer to get them off!) In either case, get these off and set them aside.

8. Now we’re going to remove the upper control arms. There is a bolt that runs through the top that “pinches” the control arms together. All you have to do is remove this bolt and tap the control arms out.

9. Now the steering arm needs to be removed. This also relies on the same concept of the pinch bolt, only it has a bolt holding it in from the top as well. Just remove these two bolts and the steering arm will come right out.

10. Now the CV shaft hub bolts need to come out. These are what we loosened in step 3. Just go ahead and remove them and set them aside.

11. Now what you have to do is to remove the CV shaft heat shields. They are bolted right into the side of the differential with 3 bolts, and they’re going to be allen bolts. This is where a long extension will come in handy as well as a set of 3/8” drive allen bits.

12. With the heat shields removed, it’s time to remove the CV shafts. There will be six bolts per side and they’ll be a M10 triple-square (12-point) bit. You’re definitely going to want this in a ½” drive ratchet attachment if you can. The easiest way that I found to remove these was to screw the wheel studs back into the hub and use a socket a long ½” drive ratchet to hold the hub still while I had a friend loosen the inner CV shaft bolts. With these out, the CV shafts will come right out.

13. For this part you’re going to want someone to help because the back part of the exhaust is quite heavy and very awkward. Loosen the 4 collar bolts that hold the back part of the exhaust to the midpipe. Now spray a little WD-40 on the exhaust hangers right where the metal touches the rubber so that they’ll slide out easier. There’s going to be 4 hangers, 2 in the very back by the rear mufflers, and 2 right by the center muffler. Now just slide the exhaust back, pop it out of the hangers, and lower it to the ground.

14. Now if you’re in a hurry, go ahead and skip ahead to step 15. If not, go ahead and get out some of your favorite beverage and take a little break, because you’re getting pretty close to being done.

15. Now you need to remove the rear O2 sensors. An O2 sensor socket works great, but a regular old open end wrench will do the trick too. The upper exhaust/midpipe has a flex point in it, so you can pull the back part down a tad to get the rear O2 sensors out. Don’t forget which side that each came out of; mark them if you need to.

16. You’re going to need that can of WD-40 again, because now we’re going to get to work on one of the last parts. The upper exhaust bolts. Some places say that you can get to the top bolts to loosen them from the engine bay. Don’t listen to them, they lie. You can barely touch them from the top, let alone get any kind of force on them to loosen them. You’re going to need to get at them from the wheel well area. For the top, you’ll need about an 8” extension and a swivel end. The other two you should be able to get at fairly easily.

17. After you’ve managed to cut your hands all to hell from trying to reach the top exhaust bolts for about half an hour, you can now take the upper exhaust off the car. This has to be done with the upper O2 sensors still installed in the exhaust because there’s absolutely no way to get them out beforehand. It’s going to be extremely tight, but the upper exhaust pipes will come out with enough wiggling and turning. Be very careful though, you don’t want to somehow manage to break one of the O2 sensors by catching it on something.

18. And that’s it, you’re done! Now all you have to do it put everything back together in the reverse order that you took it apart.

Just a couple notes on putting everything back together. The CV hub bolts need to be torqued to 90 ft. lbs. + 180 degree turn. Personally, I think this is too much so I just give it 90 ft. lbs. + 90 degrees or so, which seems to hold fine and doesn’t feel like I’m going to snap the bolt off in the end of the CV shaft. Make sure to tighten the exhaust bolts as much as you can so that you don’t get an exhaust leak anywhere. Make sure you remember to plug in the O2 sensors as the cars ECU won’t like it too much if you forget. Other than that, I can’t think of anything else that is out of the ordinary that you would need to know for this, so good luck and if anyone has any questions, just email me: [email protected]. Sincerely, Mike
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