front subframe replacement questions

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CBradio
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front subframe replacement questions

Post by CBradio »

Hi all,

Its been a while since I posted-- my car has been sitting all winter aside from the occasional startup, because my subframe hit a very high curb... :-(

I have a used/replacement front subframe that I painted, and I changed the radius rod bushings...

I went to a couple of nearby shops that are not interested in the job.

I was wondering: is this something I can do myself?

I have changed the head gasket successfully, can this be that much harder?

I know I would need to support my engine somehow, anybody have any tips for a shadetree-kind-of-guy? Any problem areas to watch out for? i.e. typical stubborn bolts or PITAs I'm not aware of?

Last, if I did find a mechanic to do the job, anybody want to venture a guess on what a reasonable cost for the labor might be? I won't hold you to it!

Missing driving my baby :!:
1977 530ia
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JodyStevens
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Post by JodyStevens »

It's not that difficult, it will just take a fair amount of time. A reasonable job for a home garage I would say. The engine will have to be supported somehow. Personally I'd use an engine hoist/crane. You'll have to undo suspensions bits and the steering shaft. Drop it down, swap over some things, ie. Steering box/pitman and then put it back together.
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CabbageFumes
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Post by CabbageFumes »

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CBradio
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Post by CBradio »

thanks guys for the responses!!

Obviously, I have to lift the car. My maybe-dumb question is, can I work on the car if it is lifted by the wheels? Its seems to me that without the control arms connected the subframe, the wheels are not meant to support the car, accurate? Or am I missing something (i.e. the wheels MUST come off)

Aside from that, everything seems pretty straightforward to me except the steering box stuff.

So you think I should disconnect it from the steering linkage and then swap steering box/pitman arm with subframe off? Is that the only way to do it?

I was thinking to somehow disconnect those three bolts, before hand.. does that make no sense?

Also, my subframe got hit on one side by the tow hook (ill try to get some pics soon, looks pretty gnarly) ... the radius bushing "box" got "shmushed" and pushed back at least an inch ... I'm hoping nothing else got bent out of whack because of this.. time will tell.

Thanks again guys for all the insight
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GripGreg
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Post by GripGreg »

Maybe you can get the tow truck company to foot the bill?
Good luck,,,,Greg
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CBradio
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Post by CBradio »

Lol greg

It drives it just pulls to the right really hard
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JodyStevens
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Post by JodyStevens »

You will need to have the wheels off the ground and free of obstruction. Support the vehicle by the front jack points or the "frame rails". First of all you won't be able to remove everything needed with the suspension loaded and second of all it will be 10x easier with the wheels out of your way.

The steering box is easier than it sounds. I would separate the steering shaft and drop it down with the box bolted to the subframe. That's going to be the easiest thing to do. Make sure you put it back on in the correct spot so maybe lock the steering wheel and mark the two halves. You may be be able to unbolt and let it hang, but that seems harder.
'78 Euro 528i Rubinrot Metallic. Who else has this color?
GripGreg
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Post by GripGreg »

OHH! I mis-read your sentence! I remembered tow truck but, you said tow hook! :roll:
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wkohler
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Post by wkohler »

There's no reason you couldn't just leave the entire power steering system in tact. unbolt the canister and the power steering pump so they will lay on the subframe. Undo the steering coupler joint and then drop the subframe. I'd take the wheels off but you could leave the struts attached to the car and just undo the steering knuckles, then swap everything else over and bolt it back up. It really, in theory, shouldn't be that difficult.

Image
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JodyStevens
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Post by JodyStevens »

That's exactly what I'm picturing to be the easiest route.
'78 Euro 528i Rubinrot Metallic. Who else has this color?
CBradio
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Post by CBradio »

Jodystevens, wkohler, gripegreg, cabbagefumes: your advice was super helpful, I successfully swapped out my subframe, thank you for your help!!!

Here are some pics of what can happen if you hit a high curb at an angle:

Image

Image
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Mike W.
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Post by Mike W. »

Wow, you hit it hard. I've seen plenty that had the toe hook bent, but not the subframe behind it.
Mike W.



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CBradio
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Post by CBradio »

Thank you too Mike!!!
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Falkenberg
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Post by Falkenberg »

Mine was hit in about the same way when I got it, moving backwards maybe 1cm. The car did go straight still, I swapped it out only when we remade the whole car. It also had a huge dent in the front valance, but fortunately no sings of other damage on the body.
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JodyStevens
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Post by JodyStevens »

Wow, hard hit! Congrats on the successful swap, glad everything went well!
'78 Euro 528i Rubinrot Metallic. Who else has this color?
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