How I swapped out my subframe + diff bushings with cradle on the car.

[mar10]

EDIT: Now that I've finished I have concluded that this is not a difficult job to do. Had I known ahead of time the little tricks I figured out, researched and learned along the way it would have gone a lot smoother. Do not let the fact that this is broken down into 7 days intimidate you from sing this if you are fairly mechanically inclined. If your able to do more than basic maintenance on your car you can do this. Had I started this and worked on it I could have had it done in a day maybe day and a half tops. But now knowing how to do it and what to be prepared for I could easily do it in a day. But I did this and worked through it a couple hours at a time and took time to document it.

I'm currently working on installing some bushings on my 2010 camaro SS. I'm taking my time while doing it because it's a lot more relaxing this way. I started the night before last and worked slowly for about an hour and a half until my wife and son came home. Last night I worked on it for about an hour and a half after work until they came home again. But yesterday I had an issue with a lug nut that I'll address later. I decided to document everything because I've noticed some discrepancies in the BMR instructions. Mainly about the socket sizes needed. I did a few things differently as well so i thought I'd share another way to do it. This is my first write up so please bear with me while I try to get it organized.

DISCLAIMER! I'm no expert or even a mechanic, I'm just a guy that didn't think this was worth paying $1,200 to have someone else install them. Just because I'm doing this doesn't mean you should or that it'll work out for you. Working on your car can be dangerous, even after your done if you screw up. So if you decide to duplicate what I've done it is at your own risk. I'm not responsible if these steps hurt you, your car or someone else or their property. Hopefully that covers everything.

First the instructions say that the sockets needed are 10mm, 13mm, 21mm. Then in step 4 it states to use a 15mm socket to remove the tunnel brace.

On the Diff bushings install instructions it says to unplug the rear O2 sensor but I don't think this is necessary at least on the Ls3 cars. It also stated to remove the exhaust hanger bolt in the rear but mine was welded on.

I unbolted the stock H pipe at the front and pulled it back before placing it on a jackstand. I went to the rear of the car and popped the metal exhaust hangers out of the rubber things they are hanging in. It was a little difficult to do laying on my back working by myself but I got it loose. I had to take the front half off of the jackstand and push it to each side in order to get my exhaust tips to clear the holes without my flow master mufflers getting in the way.

With the exhaust out of the way I pulled the driveshaft tunnel heat shield off as per the Diff Bushings instructions.

The Diff Bushing Instructions called for using an 18mm wrench and socket to remove the 3 bolts that connect the driveshaft flex joint to the differential and leave the flex joint attached to the drive shaft not the diff. This was inaccurate I'm pretty sure the size was wrong and it was a 19mm socket and as you can see in the picture below the nuts need to stay on the flex joint because that holds it to the drive shaft. So there was no need to use a wrench as the instructions state because the bolts that you remove thread into the differential. (Sorry my pics are upside down). I left the E-brake set which allowed me to loosen the diff bolts without the drive shaft spinning. I had to release the e brake and turn the tires to get the third bolt where I could reach it then reset the E-brake in order to loosen the bolt. Then I pry'd the driveshaft towards the front of the car in order to clear the alignment pin. It was tight and I didn't notice the notches in the flex joint to pass the pin through.
EDIT: When I was putting everything back together in loosened the two bolts holding what I believe it's called the carrier bearing. It is located just in front of the U-joint for the drive shaft. Doing so gave me enough play in the driveshaft to clear the alignment pin no problem. Just make sure you get it back on straight to make sure it doesn't rub the wrong way. I made sure the bolts lined up in the same spot on the bracket. You may want to mark them before loosening the carrier bearing. Also I had removed the front heart shield for the driveshaft tunnel. But this is not 100%necessary although it will give you easier access to the carrier bearing. I did not remove the rear heat shelf during this install.

This is about as far as I got the first night after about an hour and a half. That was going really slow.

[mar10]

Day 2:
I realized that I had forgotten to loosen the lug nuts before raising the car up. . One of the mechanics at work let me borrow his cordless snap on impact so I didn't have to drop the car to the ground again if the e-brake wouldn't hold while I tried to break them loose.

I tried using it and the lug nut got stuck in the socket and it didn't break loose. . I put my breaker bar on it and got it loose. I tried to knock the lug nut out using a fat Phillips head screwdriver and a hammer. It moved a little so I hit it a few more times a little harder. The screwdriver kept moving so I assumed I was making progress. I looked and noticed the lug nut had not moved any further. That's when I realized that the "cap" of the lug nut was not solid and was just denting. . I grabbed a 7/8ths socket and using the breaker bar removed the remaining lug nuts and tires. Since I don't have a bench vise I decided to put the stuck lug nut back on the lug/stud so I could try to tap the socket loose. It was Really on there and tapping it with a hammer was not getting it loose. I assumed that it might be due to the dents in the top pushing it out of shape and tight against the socket. So I tightened it down tight on the stud to try to push the dent out. I pushed the dent out and then some. I ended up pushing the wheel stud out the top of the lug nut. I finally got the socket off by using a couple of pry bars. This whole process took most of day 2s hour and a half.

[mar10]

Day 2 cont.:
The instructions for the subframe removal said to remove the calipers, undo the e brake from the spindle, disconnect the fuel pump harness and an ABS harness. I didn't do that because Im not planning on doing the cradle all the way out.

One thing I noticed was the instructions said to pull the brake line out of the first bracket by twisting it out. They didn't mention removing the bolt shown in the picture below. I then popped the other brake lines and e-brake line out of their respective brackets on both sides of the car.
Sorry the pics are upside down.

[mar10]

Day 2 cont.:

I read online that it can be difficult to remove the "hats" that hold the bushings in place. I'm not sure if it would have been better to remove them after the bushings were out but I decided to do it while they were still on the car.

I saw a couple ways to do this in my research. I used a mix of them all. First I removed each of the bolts holding the subframe in place one at a time. I believe the instructions call for a 21mm socket, that is too small. I used a 15/16ths socket. After I removed a bolt I put them back in about 6-10 turns to hold the subframe loosely while i repeated the steps with the other 3 bolts. During this process I set up a couple of jackstandseconds under the cradle to catch it in case it dropped. I heated the hats up a little with a propane torch then pry'd them with pry bars. When that didn't work I used a 2 hammer method of putting the claw of one hammer between the bushing and the hat. Then striking it with the other hammer to knock it loose. (I've always been told to avoid hitting two hammers together so this seemed like the worst way to do it but it worked the best.).

As you can see it roughed up the hats a little bit. I address that on day 3.

[mar10]

Day 2 cont.:

After knocking the hats off I moved to the bushings. I didn't take pictures of the first one I did but I have pictures of the last 3. I decided the easiest way for me to get the bushings out was the heat and socket method since I don't have a lift.

The first picture you can see what it looks like when I hung the subframe by only putting the bolt back in a few turns. 2nd pic shows where I placed the 1" socket on the metal center of the bushing after I removed that bolt completely . 3rd pic shows me jacking the subframe up to raise the car slightly above the jackstand holding that side up. The next step is to add heat but the first one I did the center popped out and left the outer ring of the bushing before I could put the heat to it.
Luckily I had the polyurethane jack pads left over from when I had my corvette. It's shown in the last picture of this post. It was big enough to fit the outside of the bushing but small enough to fit through the hole in the cradle.

4th pic shows me putting the heat to it to release the bushing. 5th pic shows what it looks like just before it pops out. You'll hear a little creaking noise as it starts to move then it'll fall out of the bottom.

[mar10]

Day 2 cont:

Due to the rear alignment pins and my plan to not completely remove the rear cradle I couldn't fit the 1" socket in between the bushing and the car to push it out. So I used 2 of the jack pads as shown in pic #1 of this post. It was important to make sure that they were both on the center metal piece of the bushing. Then the process was pretty much the same as before. Jack up the subframe to add pressure, add heat then as it started to slide jack it up more.

Pic 4 of this post shows where the jack pads will stop pushing the bushing out. I lowered the subframe and moved 1 of the jack pads to the center of the bushing then quickly jacked the subframe up to push the bushing out before it cooled.

After getting the 2 drivers side bushings out I decided to call it a night and brace the cradle with Jack stands to prevent it from dropping in the middle of the night. So at this point I'm about 3 hrs total into the project. On to day 3.

[mar10]

Day 3:

First thing I did was order a replacement lug nut and a tube of super lube through the garage at work. On the way home I picked up a can of rust-oleum.

I may be a little over cautious but I did not like the rough edges left on the hats by my removal attempts. So I knocked off the rough edges with steel wool cleaned them up then put the rustoleum on them.

Pic #3 of this post shows where I messed up on day 2. I didn't remove the melted plastic from the subframe and I let it cool and harden for 24hrs. After scraping it off and using some steel wool to remove the oem adhesive I took some measurements. Out of respect for the vendors and sponsors on here I'm not going to share them sorry but I have them incase I decide to go with delrin bushings I can have a friend make then for me.

Due to the scratches caused by scraping out the plastic I sprayed some rust-oleum in the subframe hole.

Then I put the hats on the bolts and put them in a few turns to hold the subframe up while I repeated the process on the passenger side.

Now I have the subframe bushings removed and the hats and holes prepped for the install of the BMR polyurethane bushings.

[mar10]

Day 3 cont.:

I decided to move on to the differential bushings before tightening up the subframe. The instructions say to note the orientation of the bolts and nuts holding the diff to the cradle. My passenger side has the bolt to the rear and the drivers side has the bolt to the front. I loosened them up but didn't pull them out yet and called it a day.

So far I have 4.5 hrs invested tops and that's really going slow and taking my time. Not bad for working on jack stands. I haven't gotten to a point where I got angry. So far in my opinion this is going more smooth than my headers install.

[mar10]

Day 4:
Sorry I spent today wrenching on my wife's Tahoe dealing with an oil consumption issue. I'll get back to the camaro tomorrow hopefully.

[Crash76]

Can you measure the diameter of the cradle alignment pins ? I am going to make a aluminum disk with a slot so it can just be slid over the pin... Thanks!

[mar10]

I'm still working on my wife's Tahoe . But the top of the alignment pin diameter was just slightly bigger than an inch at 1.02". The reason I couldn't fit the socket in was I didn't feel comfortable lowering the cradle low enough to get a big enough gap between the bushing and the pin. Make sure you get the diameter big enough because the alignment pin is tapered.It may fit the bottom fine but once you put weight on it the piece your using could get stuck.

[BMR Sales]

Good Write Up. The one thing about Heat is that I have been told by some customers that the Rubber Vulcanized & got harder with heat

[mar10]

I basically melted the plastic sleeve to pop it out and didn't have any issues with the rubber. But the bushings are useless one you start to get them out this way.

[mar10]

I don't understand why some of my pictures post fine and others post sideways or upside down.
Day 5: Diff Bushings

I got pretty frustrated today but found a solution that made it simple.
Pic 1 shows the rags I put under the CV boots to protect them from tearing on the subframe and it being supported by a jack. I loosened the front two bolts and nuts and lowered the front of the diff to gain access to the bushings. Be careful how much you lower it there is a vent tube on the top that might rip off.

Pic 2 shows the bushing. I used a 2" hole saw and drilled the center out. My little black and decker drill did not have enough power to make it all the way through. I put my pry bar into the rubber part of the bushing and hammered it in to finish ripping the rubber "tabs" that hold the center of the bushing to the outer part. Once those were ripped the bushings pushed out easily by hand.

Pic 3 is the core of the bushing I drilled out. You can see the thicker part of the bushing that was left on when I used the pry bar to rip it loose.

Pic 4 shows the bushing sleeve still in the diff. and the mess left from drilling out the bushing core. The instructions say to use a screwdriver to bend the sleeve so it can be removed. Good luck with that.
First I tried to pry the screwdriver behind the front of the sleeve and hammer it in but was unsuccessful with that.

Pic 5 and 6 I tried to hammer a screwdriver into the backside and that did not work. So using some metal shears I cut a slit into the back of the sleeve hoping that it would tear as I hammered the screw driver into the back of the bushing.

The instructions made it sound so easy to pop the sleeve out that I just kept pounding away instead of searching for better options to get it out. About 4 hours of pounding and prying on it with little progress I decided to search around and found that this was not as easy as implied by the instructions. I found several different ways that included an air chisel and sawzall. I didn't feel comfortable taking either to my diff so I grab a plumbers hacksaw (basically a small handle that you attach hacksaw blades to) from my tool box and started to try and cut the bushing out. That was taking forever even after changing to a fresh blade. Finally I got to the "F" it point in my frustration and went to town and bought a sawzall and a metal blade. It took me 10 min tops to get it out after coming home with the sawzall to get the sleeve out. I carefully cut through the length of the sleeve and the front of the lip on the sleeve. When your cutting you might feel the blade kind of grab or catch that is when your through the sleeve but you need to work slowly and keep checking to make sure you don't cut into the differential.

Pic 7 After the cut is made the sleeve can easily be tapped out of its hole using a screw driver and hammer.

Pic 8 I got tired of holding the driveshaft out of the way and wish I would have thought of it earlier when I was drilling the bushing out. Putting a screwdriver into the bolt holes where the diff mounts to the flex plate will hold it out of the way.

Pic 9 The second bushing was much easier to get out using the sawzall. you can see how far I got with the 4 hours of pounding on the first sleeve when compared to the second sleeve.

Pic 10 Just a comparison of the bushings new vs. old.