Rear subframe

[ahtim]

Hi guys, as we all know e46 do have rear subframe crack problem, but what do you guys do? Replace the whole rear subframe at bmw, or use those plates and strength it?

Thanks

Will

[Chad]

Hi guys, as we all know e46 do have rear subframe crack problem, but what do you guys do? Replace the whole rear subframe at bmw, or use those plates and strength it?

Thanks

Will had full floor done on both cars,done on bmw warranty,, but think that’s over now. But also bmw refused to repair full floor for a second time on one car but plated it,so I guess they think that is ok also. :whistle:

[GregorFuk]

Redish

[CraigMillwardCroft]

Mine was not cracked so Gareth resin filled it :thumbs:

[Chad]

Mine was not cracked so Gareth resin filled it :thumbs:

Must drive like a girl. :blalalala: or get Gareth some stronger glasses

[ahtim]

Thanks, what about other guys? What are he differences between replacing the whole rear vs those aftermarket plates. I have had the car for 9 years now, I will probabaly keep it for much longer.
What would you guys suggest? Do it at bmw or plates?
Thanks

[Mike R]

As long as the repair you have also has the sandwiched area resin filled, then it is all much of a muchness.

The BMW repair removes the entire area and replaces with new, so effectively the repair is undetectable (if done correctly), where the plates are visible. So it depends which is more important to you.

[Trawler]

Must drive like a girl. :blalalala: or get Gareth some stronger glasses

:hahaha::hahaha:

[Trawler]

had full floor done on both cars,done on bmw warranty,, but think that’s over now. But also bmw refused to repair full floor for a second time on one car but plated it,so I guess they think that is ok also. :whistle:

If I remember correctly NZ M3 gave a good explanation using a Coke can why plating did not work. This is going back some time so I could be completely wrong.
Would need to go back through old threads

[0-60Motorsports]

Vincebar plus the Vince plate. If you havent heard of them search on M3F or go here:

https://www.facebook.com/PPRnDnews/

[GregorFuk]

If I remember correctly NZ M3 gave a good explanation using a Coke can why plating did not work. This is going back some time so I could be completely wrong.
Would need to go back through old threads

Plating on it’s own does not give a lasting repair, nether will replacing the whole carrier panel. It’s the resin injection that makes the difference. As long as this is done either repair works well.

[0-60Motorsports]

Plating on it’s own does not give a lasting repair, nether will replacing the whole carrier panel. It’s the resin injection that makes the difference. As long as this is done either repair works well.

Even the resin injection won't be as good as of a solution than the vincebar. I'll post a link later to show how the bar works and the thought process behind it.

[GregorFuk]

Even the resin injection won't be as good as of a solution than the vincebar. I'll post a link later to show how the bar works and the thought process behind it.

Perhaps but just how far do you want to go? Redish have a number of videos reviewing repairs performed a number of years ago now and since exposed to heavy track use. All have stood up fine. Vincebar might be better but you’re into deminishing returns.

[0-60Motorsports]

Perhaps but just how far do you want to go? Redish have a number of videos reviewing repairs performed a number of years ago now and since exposed to heavy track use. All have stood up fine. Vincebar might be better but you’re into deminishing returns.

True. I have the plates and I'll be doing the vincebar epoxy method sometime this year.

[Chad]

Plating on it’s own does not give a lasting repair, nether will replacing the whole carrier panel. It’s the resin injection that makes the difference. As long as this is done either repair works well.yep Gregor , seems that either full floor or plate inc resins is just a repair, when the car gets used looks like they will go again :whistle: gesss we just have to face it e46 boot floor is a bummer,, when it breaks “again” looks like we just have get on with it and fix it again, :banghead: ... suppose its part of the fun running a e 46 m,,,,must check the mileage when second fix was done , garage queens needn’t worry

[Trawler]

At 10 years I had the full floor replacement & resin carried out.
Hopefully it will not need renewing before the 20th anniversary tour.
I think the lack of spare parts in the future will become the major worry

[0-60Motorsports]

https://youtu.be/DOQlbVhstzg

[Chad]

Lovely job ,, almost as satisfying to see as doing your own refurbishment,, Hopefully it’s for yourself to get the pleasure from and not sell on , but a really great job ,, got be be £10 k + but well worth it :thumbs::thumbs: That underbody will be very typical of 90 percent of every csl ,,

[JBird]

Hats off to Redish and the owner for such a thorough job. Makes me want to do the same.

...but did I miss a bit of the video or is this just plates and no resin injection? Despite what they say in the video about the plug welds to connect the floor skin inner and outer, I can help but think its only going to crack again without the injection.

[Chad]

Hats off to Redish and the owner for such a thorough job. Makes me want to do the same.

...but did I miss a bit of the video or is this just plates and no resin injection? Despite what they say in the video about the plug welds to connect the floor skin inner and outer, I can help but think its only going to crack again without the injection.
Yep. But they will crack again anyway ,as I’ve said earlier! you could argue it’s better without the resins,, as one of our cars cracked again with resin and full bmw boot floor, I suppose making another repair more difficult.. ,,:banghead:

[Chad]

Haha perhaps were at the point where spair boot floor is part of our parts stock :smokin:

[select]

Why not go with solid mounts?

[Chad]

Why not go with solid mounts? nice though but living in the Manchester area , the roads are that bad, really isn’t fun driving on a lot of these roads, that many crap repairs to road surfaces spend most of the time dodging them,,,solid mounts probably rattle car to bits..:banghead:

[JBird]

Why not go with solid mounts?

Higher peak loads - it will crack even faster.

Chad, interesting that you had one with the resin injection crack again. If you have any photos it would be interesting to see where it failed, and how well the resin was injected / bonded to the surface etc. I have always though if done properly it should hold, but wasn't too confident the monkeys doing the injection would get it all in the correct spot.

[Chad]

Higher peak loads - it will crack even faster.

Chad, interesting that you had one with the resin injection crack again. If you have any photos it would be interesting to see where it failed, and how well the resin was injected / bonded to the surface etc. I have always though if done properly it should hold, but wasn't too confident the monkeys doing the injection would get it all in the correct spot. hi,this was a bmw Repair full boot floor with resin, I’m confident the body shop did a good job even though it was probably one of the early cars to be done, bmw then wouldn’t do a second full boot floor, but they plated it ,, apparently bmw don’t warranty full boot floor warranty replacements:whistle: but this was lads car, don’t think he’s really bothered as it’s still ok I think,,

[select]

Higher peak loads - it will crack even faster.



Yes, because the subframe cracks because of peak loads ;). No it doesn't.
To cut it short the subframe cracks because the oem bushings wear out and allow for play between the carrier and the subframe which the subframe wasn't designed to do cope with for longer periods of time.


@Chad i have delrin bushings installed with 100shore, so they are near solid aluminium regarding hardness, and the ride become only a tiny bit harder. Granted i never drove on UK roads yet.
For me it was worth it, the car feels alot more planted and you have rectified the cause itself.


There is a reason the GTS on the E9X Gen got solids installed per factory.

[Chad]

Yes, because the subframe cracks because of peak loads ;). No it doesn't.
To cut it short the subframe cracks because the oem bushings wear out and allow for play between the carrier and the subframe which the subframe wasn't designed to do cope with for longer periods of time.


@Chad i have delrin bushings installed with 100shore, so they are near solid aluminium regarding hardness, and the ride become only a tiny bit harder. Granted i never drove on UK roads yet.
For me it was worth it, the car feels alot more planted and you have rectified the cause itself.


There is a reason the GTS on the E9X Gen got solids installed per factory. hi Julian I’ve thought about picking up a spare subframe and solid bushing that. may well try this just for fun ... :smokin:

[select]

I would really recommend you to give them a shot, Chad.
I think the ever so slightly increase in harshness is negligible for the upsides, especially if you don't daily drive your CSL.

[shawn 968cs]

https://youtu.be/DOQlbVhstzg

That looks familiar :whistle:

[Chad]

That looks familiar :whistle:
Lovely job almost as good as my garden shed refresh :blalalala: typical underside even a full service history doesn’t address the underside where it really counts,, love the comment nearer end of video regarding air filter after bmw service,, hope they post the reply’s name and shame :whistle:

[khooni]

my rear subframe is solidly welded after I had the plates done.

full disclosure..... ride quality doesn't come into any of my considerations.

[0-60Motorsports]

my rear subframe is solidly welded after I had the plates done.

full disclosure..... ride quality doesn't come into any of my considerations.

Nice mate! Now add the Vince bar to complete your project.