subframe: questions about use of BMW3026 tool

[BRRV]

I'm getting ready to buy tool BMW-3026 that is used to remove and replace the subframe bushings, probably from ZDMAK or Sirtools. I have some questions about the use of the tool on my E28. I'm assuming I'll get more specific instructions with the tool when it arrives; nonetheless, I wanted to make sure I understand this procedure and technique thoroughly beforehand, as getting in there and getting stuck isn't an option. By the way, I'm also removing the axle shafts and trailing arms for service (new joints and bushings) at the same time, following the Bentley R&R procedures (I'll also be removing the push rods from both sides). FWIW, I've reviewed all of the posts and topics concerning subframe bushings that are available, both here and on the 'web. Here goes:

1. The use of the 3026 tool would appear to require the removal of the pin that is inserted through the body structure underneath the rear seat, after removal of the nut, typically with a BFH, an air tool, or drilling, before use of the tool to withdraw the worn bushing from the axle 'cup'. Is this correct?

2. The car needs to be supported in front of the subframe, obviously, using, for instance, the 'car jack' reinforcements on the under-frame in front of the rear wheels. Any recommendations, procedures, or ideas on how best to support the car here on jackstands (not an area that is specifically built for this purpose, to my mind) without damage to the underbody?

3. As mentioned, the rear axle carrier is attached to the frame via the pin/bolt through the bushing, as well as one of the pitman arm bolts (the other pitman arm bolt isn't attached to the body, but rather to the carrier itself). Removing these 4 bolts and nuts (2 each side) would appear to be all I need to do to get the subframe to descend from the frame, assuming no interference from corrosion. Do I need to remove any of the 4 diff bolts and support the diff separately, or is this unnecessary? (To my mind, it's unnecessary).

4. I'm assuming I have to pull the subframe/axle carrier away from the body in order to place the upper portion of the tool at the top of the bushing cup (where it formerly was seated against the frame under the rear seat) in order to push the threaded rod/bolt apparatus through the center of the old bushing before connecting the top and bottom of the tool, from which I will pull the old bushing out. Is this correct? Or, if not, what is the correct way to use the tool? As a follow-up, is this typically difficult, as in, I'll need a helper and more BF-hand tools?

5. In removing the bolts that hold the rear axle carrier to the frame, should I support the subframe from below in any specific way, such as with a floor jack? To expand this question a bit, it would appear that the forward diff bolts would prevent the rear axle carrier from falling to the ground while giving me some room of maneuver to install the upper portion of the tool, assuming that my conclusion in Q.4 is correct.

6. Lastly, I've had a couple of positive comments on the Ireland Engineering urethane subframe mounts, and am considering using a set of these, rather than the rubber-encased Lemforder OE bushings. Does anyone have any direct experience with installation of these bushings? I suspect that they would install easier, because they don't need to be (or can't be) compressed in quite the same way as the OEM units. Your answers, comments and opinions would be welcome.

Thanks in advance...

[Rich Euro M5]

As I've mentioned in the past, my Indy mechanic drops the subframe. Since he has the lifts and needed stands, it's easier and he doesn't have to remove the BIG PIN with a BFH or air chisel.

If you do decide to acquire the tool, don't use soapy water, KY Jelly or any of the other concoctions others have tried. I asked my Indy and he said the factory uses a type of mineral spirits which is bascially turpinetine. He told me it softens the outer rubber coating, this coupled with the turpintine acts as a lubricant when installing the new bushing. When the turpinetine evaporates, the rubber bonds to the subframe sleeve and doesn't continue to move about like it does when using soap solutions and other elixers.

FWIW: He's been servicing BMWs as an Indy since the late '70s.

HTH

Rich

[M635CSi]

[JBort]

Rick, having assisted in several subframe bushing replacements using "the tool"(around 10 e28's), I'll give you my 2 cents:

(BTW, we've always done this job on a lift)

1. Yes, the pins must be removed. Sometimes they pop right out (reusable), sometimes they have to be drilled to relieve the pressure, then hammered out. Always have a new pair of pins.

2. The rear of the car needs to be supported off the rear subframe; the jack points work well.

3. The only bolts that need to be removed are the subframe pin nuts and those bolts forward, 2 each side, supporting the "push rods"(pn.33 31 1 123 982 in the ETK). Be sure to mark their position as the holes are slotted.

4. The subframe will lower sufficiently to use the tool; no additional items need to be unbolted.

5. Yes, we actually do one side at a time, supporting the subframe with a lift-jack. You can still allow the subframe to lower sufficiently.

6. We've installed : (a)stock BMW (b)Mahle HD (c)Urethane-filled stock. Stock were easiest, Mahle were OK (and best performing), urethane were difficult and the people who had them installed hated them a week later!
We've only used soapy water. Haven't tried other lubes.


Michael is pressing the old bushing out


When all else fails, you have to drill the head of the pin


New bushing being pressed in.

[Blue Shadow]

I have used both BMW tools and they both require the removal of the stud holding the bushing. Not too bad, but it does take a few hits from the BFH. I have never used a lift and have only done 4-6 sets. We did Chip in PA's set a couple weeks ago with a tool like the BMW3026, the BMW 2336 from TechnicTool http://www.technictool.com/bmwsuper.htm which allows the use of air. Nice improvement over the other BMW tool which does not. Takes about 15 minutes to pull and install the bushing using fire to lubricate them on the way out (the rubber melts/burns) and water with one single drop of dish washing liquid per quart for the install.

If there is any 5erFest money left, the community could start a toolbox for things like this. Require a deposit and shipping payment in advance and return the deposit when the tool is returned. Most folks probably need to do this job but will only need the tools once. You gotta know there are folks that would be glad to manage the tools.

[wkohler]

Now, I have to do half of this job in the dirt at a salvage yard. I need to remove my subframe so it can go in the next car. I also wan to save the urethane bushings if possible - they were just put in.

When I actually install it in the other car, it will be done on a lift, but can this really be done with floor jacks?

[BRRV]

Replies have been appreciated and informative, especially JBort. Thanks to all. Lots of very good tips and tricks.

JBort, with regards this comment re. Q.3:

[Duke]

Great pictures JBort!

[JBort]

[John in VA]

Looks like nice new "dog bones" in JBort's pic above, too.

[BRRV]

Thanks, I didn't know about the slotting in the push rod. Great pictures, too, might I add. Very informative, and helped fill in the final gaps I had with this. All in all, with the right procedure, it's well worth buying the tool - especially since I can use it on the various E30's I have around here...

[swatterssr]

I've got to do this on my newly purchased E28 M5 and do not have the special tools you've mentioned.

I've read Rod's, http://mysite.verizon.net/vze7aq8e/continued/, comments and I've also read the, not recommended alternative "saws-all" method, http://www.tycksen.com/bmw/tech/subframe/.

Any help, comments, recommendations, etc. would be greatly appreciated.

BTW - I'm going back in with Febi-Bilstein, http://www.autohausaz.com/search/product.....e/Differential%20Mount, bushings as my car will be used primarily as a weekend driver and possibly daily if needed while repairs are being done on one of our other E28 daily drivers.

Subframe studs are soaking in 'PB Blaster'.

[louielouie]

I bought this tool from Pelican Parts who had the cheapest price. The HD Mahle bushings have a slightly larger flange and were difficult to get in - the base plate was slightly bent afterwards. I used a 'personal lubricant' when pressing the new ones in and it seem to work well enough.

[swatterssr]

http://www.pelicanparts.com/cgi-bin/ksea.....=ON&FILTER_TOOL=ON

$373.60 That's

Anyone in Houston got one to loan?

[wkohler]

I see 3 E28s there in your signature. To me that tool would be worth it. It's less than having a shop do them.

[swatterssr]

[Zaffer]

To resurrect an old thread here:

It seems to me that buying the tool to replace these bushings once is a pretty expensive way to go. Taking to the mechanic is less expensive, but still expensive.

I looked at the "saws-all" method and it seems pretty straight forward, but I was wondering how hard it would be to remove the subframe and use a hydraulic press to do the bushings.

Would I have to remove the trailing arms from the car or anything else to remove the subframe, and how likely is it to be able to use a shop press to change out these bushings?

[swatterssr]