Another rear subframe thread.

[FredK]

Well I'm using polyurethane mounts, so they slide in without too much fuss. The original rubber ones need a little coaxing with some dish liquid. I believe PiercedE30 says he installs em with a bottle jack.

[funcrew]

A little story of skinning the cat a different way.

I wanted to remove the subframe without removing the rear section of the exhaust, which could introduce its own set of problems. But, my trick is applicable to anyone wanting to quickly remove the bushings from the body (2-3 minutes a side).

So, to start, I removed the subframe rubber hanger, and loosened the straps so the exhaust could hang down a little. I supported the exhaust tip with a jackstand, to avoid straining the back section. I removed the M14 studs that pass through the center of the subframe bushings.

I think rocking the subframe back and forth will place the exact kind of shear loads on the tops of the bushings that will cause the top of the bushing to break off in the body. So, one of the ways to do this is to tap the bottom of the bushing with screw threads, screw a bolt into the bushing, then pound on the bushing from up top.

Good luck finding an M16 tap and bolt. An M16 tap ain't cheap either. You could use a 5/8-11 tap. But these cost $25. Screw that! :nice:

I decided to get a 5/8" lag bolt (less than two bucks at Lowes) and thread it into the soft aluminum bushing and pound it from up top. Worked like a charm. I put a 1 foot 3/8" extension inside the subframe pin bores while inside the car, and pounded on it a few times to break the bushings free.

This sounds quick & easy but... having not yet tackled subframe bushings, I'm having a hard time picturing it. Has anybody else done it like this that could describe it differently? Diagram? DIY with pics?

[Naplm00]

BACK FROM THE DEAD!!!!!!!!!!!!!!!!

Just wanted to put in my comments about cabrios:



we cannot EASILY pound the lag bolt from the top due to how the body is constructed from above

TO be able to pound it out, you need a 3 foot steel rod, I got one from lowes (cold rolled for strength) for about 6 bucks


follow all of the above directions then thread in the lag bolt as far as it will go then pouund out from above


This only worked on one side for me..the other side i had to threadin the lag bolt and hit the back and forth horizontally so it would break off the aluminum inside the body.


I then used a dremel and a rotzip bit to cut away a portion of the siezed in alum sleve and tap the remaining out with a hammer and chisel.



Good luck, having a cabbie make this job even harder

[MIKe30]

I had a shop press what was left of that metal cylinder out of the subframe as well as do the diff mount and my rear wheel bearings for 150.

Fred,
I am very interested to hear about your issue with your subframe when you raise/lower the car. I installed the powerflex race subframe bushings and when I place the subframe on jackstands it actually moves vertically alittle. When the car is placed back on the ground everything returns to normal. Everything was assembled correctly so the only thing I can assume is that the 2 piece bushing seperates alittle when the car is raised.


-Nick

So is that ok, or not ok? I had this happen to me with my swap car. Supported the rear of the car with jack-stands under the subframe and not the subframe bolts, resulting in subframe staying still but the rest of the car lowering a bit. In other words, it was like the subframe shifted vertically.

That mean my bushing are completely shot or are they ok, maybe just a litte worn? Have an HPDE coming up, if they're not ok then looks like I have work ahead of me...

[MIKe30]

So is that ok, or not ok? I had this happen to me with my swap car. Supported the rear of the car with jack-stands under the subframe and not the subframe bolts, resulting in subframe staying still but the rest of the car lowering a bit. In other words, it was like the subframe shifted vertically.

That mean my bushing are completely shot or are they ok, maybe just a litte worn? Have an HPDE coming up, if they're not ok then looks like I have work ahead of me...

.

[jduffett]

That was my first indication that they needed to be replaced. I subsequently did a 6000km road trip. I have signs now that my CSB is and/or flex disc are in poor shape, and I suspect driving with weak subframe bushings may have caused/exacerbated this problem. In one of my bushings, the aluminum core was split (and had been for some time judging by the surface), and both had rubber separated from the core.

[FredK]

The subframe bushings are meant to have a little vertical flex. However, as jduffett has experienced, if they move quite a bit, the aluminum core likely has started to separate from the rubber portion of the bushing, and the bushings will have to be replaced.

[LJSE34]

Subframe bushings VS 12 ton press. Subframe wins, the bushes are just laughing at me, sigh...

[vtman05]

Burn the bushings out!

[She loved E]

To get the RSBs out I ended up using a drill to cut out the center portion of the bushing, then a hacksaw to cut through the metal like so: http://www.r3vlimited.com/board/showthread.php?t=74184

I had access to a 20-ton press but there was no good way to maneuver the subframe in it; I tried the "torch the mf" method too and that shit wasn't going anywhere. With that said, adding some heat after you get the metal cut will help the remainder of the bushing slide out.

I'm trying to drop the old subframe out of my car now... I didn't know it was easier to get the e-brake cables out from the cabin, so I'm glad I checked before trying to crack open the drums.

[craz azn]

Burn the bushings out!

And burn the rest of your car with them! Sounds like an awesome plan!

Seriously though, use lots of caution when doing so, a friend of mine accidentally got his car a bit hot, and the fire travelled a bit higher up than expected, marring his interior.

[whiltebeitel]

I'm gonna go out on a limb, since he mentioned using a 20-ton press, I'll bet he wasn't dragging that press up under the car, and instead had the subframe free of the car, making the torched bushing more of a "toxic smores" event than a "you burned WHAT down?" event.

[She loved E]

now what?

OK, I'm stuck. The subframe is ready to be removed, but its not dropping. I presume I'm a lucky winnar with metal sleeves fused to car. The subframe nuts have been removed but the subframe hasn't budged at all.

I guess my options now are:
-Drill out the center section of the bushings, but then I'll still have bits stuck to the car that need to be taken care of.
-I could keep hammering on it, but not sure what that would accomplish.
-Start removing bits (diff, TAs, etc.) but again I will be left with subframe attached to the car.

Any advice?

[jrdeamicis]

MAPP torch, glasses, protection [not the baby type].

Get it on fire, keep going. Then hit it.

[She loved E]

ok, nm I got it. Lag bolt & hammer method worked. :twisted: