Cabrio Rear Subframe removal

[BaltimoreBimmer]

I just removed the cabrio subframe bolt yesterday. On my car all I had to do was hit it with an air chisel from the bottom. 2 seconds and it popped up. The bolt is hidden behind the rear panel.

they showed how they bent a rod to hit the bolt from above

I'm confused. People are saying they hit the bolt from below and it pops up. But then others are saying to bend a rod and strike the bolt from above in a downward motion??? How can both of these methods work? Looking at the realoem diagram,the bolt appears to have a head:

https://www.realoem.com/bmw/enUS/showparts?id=BB13-USA-11-1990-E30-BMW-325i&diagId=33_0213

So how can you hit that down? Wouldn't it catch on things? \

Regardless, I have tried hitting from below to no avail. I also jacked the car up via this bolt but it just lifted the car! The bolt didn't budge...

Not sure which way to hit this bolt. From the top or the bottom???

edit: obviously figure it out (sort of) after posting... so it looks like you pound the bolt UP, then use the rod to pound the bushing DOWN.

edit2: after a while none of the above actually did the trick for me. for those interested I ended up putting a mini jack between the upper spring perch and lower spring perch (ish, but a bit up onto the arms) and it came out. I wouldn't recommend doing it that way but it's all that worked for me. I didn't take any pictures b/c it was pretty sketchy

[Mook613]

You got the idea but left out a key step.
To start you use a BFH to hit the bolt upwards from under the car and have it pop out. Then remove that bolt by fishing it out from the inside of the car.
Step two, the critical step that you left out, is to use a 5/8 inch lag bolt and screw it as hard as you can into the bottom of the bushing sleeve. Really wrench it in there.
The last step is to use the bent rod (I think it was 1/2", but could be mistaken) and feed it through the top of the car and into the top of the bushing sleeve.
The idea is that the rod is then pressing on the top of the lag bolt.
Last step is to take your BFH and give the top of the rod a few big hits.


Sent from my SM-G920W8 using Tapatalk

[mrpenny]

I just took my rear subframe out this afternoon - tried the 1/2" bent rod from inside the car without success, but I came up with a different way that eventually worked - figured I would share.

Use the 5/8 lag bolt, thread it into the bottom of the subframe bushing as before. Then I made a "fork" out of some spare steel pipe that I had laying around - slipped the fork over top of the head of the lag bolt and supported the other end with a block. Then I used a BFH to hammer the pipe down away from the car.

I feel like it was a lot easier because you can see everything you're hitting and there's not chance of deforming the pocket for the spline bolt inside the convertible.

Now I just need to figure out how to clean the counterbore as some of both bushings remained in the car.

[Mastrcruse]

From the YouTube videos I’ve watched on “ in car” changing rear subframe bushing I notice them working inside of the care to pull the new bushing up into the subframe. If I take the interior side panel off, will I see the subframe bolt head?

[jeffnhiscars]

When I pulled my cabrio subframe I never found the head of the bolt from inside. When subframes freeze to the body itsntypically the metal sleeve on the bushing itself that sticks to the recess in the body. It's that aluminum to steel co tact that causes the problem...in spades if the car has ever seen salt. Point being that the bolt itself which is splined at the top usually will let go with a hefty whack. Just put the nut on first so a) you dont damage the threads and b) so the bolt doesn't fly out the top in to a body cavity. Once the bolts are loose I just jammed some bits of foam part way up the bushing sleeve to hold the bolt out of my way. From there, dropping the subframe in business as usual.

[Mastrcruse]

When I pulled my cabrio subframe I never found the head of the bolt from inside. When subframes freeze to the body itsntypically the metal sleeve on the bushing itself that sticks to the recess in the body. It's that aluminum to steel co tact that causes the problem...in spades if the car has ever seen salt. Point being that the bolt itself which is splined at the top usually will let go with a hefty whack. Just put the nut on first so a) you dont damage the threads and b) so the bolt doesn't fly out the top in to a body cavity. Once the bolts are loose I just jammed some bits of foam part way up the bushing sleeve to hold the bolt out of my way. From there, dropping the subframe in business as usual.

Thanks. I was trying to replace the subframe bushings without removing the entire subframe which, with the technics I’ve seen on YouTube, require that bolt to come out so that I can “pull” the bushing up into the subframe.

I’m wondering, if i have to remove the entire subframe to replace the bushing, does it make sense to send it to gargastic and get it reinforced, powdered, refreshed? Doesn’t look like there is an easy way to replace subframe bushings without removing the entire thing on the vert.

Maybe the bolt heads are under the side interior panels?

If I’m refreshing everything - does it make sense just to do all of it right even if I’m not adding a lot of additional power? Even thinking about doing the refresh on the front subframe too.

[jeffnhiscars]

Thanks. I was trying to replace the subframe bushings without removing the entire subframe which, with the technics I’ve seen on YouTube, require that bolt to come out so that I can “pull” the bushing up into the subframe.

I’m wondering, if i have to remove the entire subframe to replace the bushing, does it make sense to send it to gargastic and get it reinforced, powdered, refreshed? Doesn’t look like there is an easy way to replace subframe bushings without removing the entire thing on the vert.

Maybe the bolt heads are under the side interior panels?

If I’m refreshing everything - does it make sense just to do all of it right even if I’m not adding a lot of additional power? Even thinking about doing the refresh on the front subframe too.

I've never used the special tool so don't know. What I do know is that the worst part of this is getting the subframe free of the body and that once that's done "do it once and do it right" so you never have to do it again. Drop the subframe and replace: subframe and TA bushings, inner brake lines, diff carrier bushings and flange o rings, rear wheel bearings, fuel filler hose and rubber sleeve and freshen the parking brake as needed.

i havent reinforced a rear subframe but now that I have a good reasonable powder coaster I would personally go that route. Otherwise eproxy chssis paint and I wouldn't bother shipping it anywhere, but it's your car and your wallet :)

[Mastrcruse]

I've never used the special tool so don't know. What I do know is that the worst part of this is getting the subframe free of the body and that once that's done "do it once and do it right" so you never have to do it again. Drop the subframe and replace: subframe and TA bushings, inner brake lines, diff carrier bushings and flange o rings, rear wheel bearings, fuel filler hose and rubber sleeve and freshen the parking brake as needed.

i havent reinforced a rear subframe but now that I have a good reasonable powder coaster I would personally go that route. Otherwise eproxy chssis paint and I wouldn't bother shipping it anywhere, but it's your car and your wallet :)

Thanks. This is what I was thinking. Just do it right the first time.

You bring up some other good pieces to look into though - like the inner brake lines and fuel filler hose and rubber sleeve. Didn't think of these but I'll inspect when i get under there.

I was looking at wheel bearings....how about hubs?

You are talking hard lines, correct?

https://www.realoem.com/bmw/enUS/sho...diagId=34_0153


For the fuel filler hose..are you talking 11 and 13? Or other parts?

https://www.realoem.com/bmw/enUS/sho...diagId=16_0219

[jeffnhiscars]

Thanks. This is what I was thinking. Just do it right the first time.

You bring up some other good pieces to look into though - like the inner brake lines and fuel filler hose and rubber sleeve. Didn't think of these but I'll inspect when i get under there.

I was looking at wheel bearings....how about hubs?

You are talking hard lines, correct?

https://www.realoem.com/bmw/enUS/sho...diagId=34_0153


For the fuel filler hose..are you talking 11 and 13? Or other parts?

https://www.realoem.com/bmw/enUS/sho...diagId=16_0219

11 is a hard pipe. You want the hose #15 and sleeve #13. Only deal with the brake hard lines if they are corroded. Otherwise there are 2 soft lines that go from the T above the diff to the trailing arms and they are a bitch to replace with the subframe in place. The hubs should be reusable and IIRC you will need axle nuts and dust caps and def check the condition of the rubber boots on the half shafts