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We all know the issue with the rear subframe and we all know the various ways of tacking the issue. But it seems that some of these methods are not really fixing the problem
Now I don't want to get into a debate about which way is best but if you were in the market for an e46 m3 would you buy one with the work already done or one that hasn't been touched.
Personally I think I would buy one untouched
Thoughts?
If I was in the market I'd be wanting it done already and there's receipts from Motor Confidence for subframe work - that's the only way I'd be sure it would be done right.
But the repairs (welding in plates) that people have been doing are only kicking the problem down the road and not actually fixing the problem?
If you're buying for the long term I'd probably prefer to buy one undone and get it dealt with and documented to a known standard, unless it was done by BMW or a very well renowned specialist, with appropriate documentation/details of who, what, when and how.
Marc (Schooner) has a great write up on the sub frame fix, it seems to be a permanent fix but a lot more than the reddish plates and welding is involved.
http://www.bmwhaus.ie/vbulletin/show...light=schooner
I'd buy either, tbh I'd probably prefer one where the work was already done but only by a known quantity.
Given that most cars have 75k+ miles at least and only have a few cracks to show for it I'd be happy enough to buy one with the plates in on the assumption that it'll be a cold day in hell before the car does another 75k in my ownership.
To get it "properly" fixed, is a lot of money + labour + knowledge.Quote:
Originally Posted by eamo
I got Motor confidence to do mine with reddish plates plus various other jobs due the lack of the above. Zero complaints.
Majority of m3 owners get redish plates and I havent come across a thread where the subframe cracked again... Unless if you track your car all time maybe, even then..
Not quite comparing apples with apples here but just to highlight that mileage, etc. is no real determinant of when the problem might occur, our old e46 328i Touring was repaired by BMW at less than 6 years old, with 40k miles. That is a car that was the proverbial one lady owner, never been raced example.
Either way tbh but depends on what actual repair was done to the car if it was done.
Everybody has there own theory on how they should be repaired. My own theory is once the affected area has been repaired and plated then this is good enough. But this is only in cases where there's minimal cracks. If there's bad ones then further action needs to be done.
I've seen a good few E46s with repairs done to the floor that years later are still fine.
I love the way Schooner went about doing his but each to there own.
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Schooners approach is the best I've seen to date (belt and braces). If I was buying I'd buy untouched and try to emulate the Schooner way lol
I didn't see any belts, only the braces! :DQuote:
Originally Posted by 318is-joe
Bottom line is when you're going in to buy an e46 M3 this problem has to be factored in. Dare I call it almost a "service item" at this stage. If it's not done, you know you have to do it.
Yeah, that pretty much sums it up.Quote:
Originally Posted by rebel.ranter
I would buy an untouched m3 and get it done yourself because you have no way of knowing the standard / method used if buying "repaired" I use repaired in quotation marks because IMO alot more work is required to repair and prevent the issue from arising again. What a lot of people offer is too basic and has been made redundant by better techniques .Although if someone could show a detailed description and I was happy with the repair then I would consider it.
As I said before about plating is that while its helpful and I recommend doing it, it is not addressing the primary cause and the visible cracking on the undercarriage is only secondary to the root cause. Root cause is basically a design flaw and the panel is trying to separate itself from the the surrounding supporting panels and at the same time the upper anchors of the front subframe mounts (behind the seat near the seat belt anchor) is simply to weak and breaks away resulting in excessive movement in the mount eventually weakening and allowing the underside lower skin crack and this is what everyone see's and tries to "fix". Without fixing the initial problem your going to have bigger and more expensive complications down the line.
I cant take credit for the repair I did as I saw it on another forum and copies it albeit having my own little tweeks an extra measures taken.
The same guy went to a scrap yard and was looking at e46 non M's to demonstrate that it happens to low power cars too as previously mentioned by Dergside.
http://www.m3forum.net/m3forum/showthread.php?t=552534
Thew first , its factory shite job on cars body ! Not subframe fitting ,but whole badly engineered car chassis ,in general .
BMW fix , change floor and use some glue-foam inside the floor ? what a joke i would say ,in my opinnion, they didnt change it to something better ,just replace it afaik , so its not fix anyway ! the glue ? i think its only to let U think its fixed .
Turner motorsport plates ,half the size of Redish plates and still does the job as i have seen .Redish plates,does the job perfect as well .
Have done one car very badly cracked , think should be pictures here on the forum , seen it year or more later,and still perfect , of course its not guarantee how long it will be perfect , but there is nothing forether in this life !
Years runs , everything changes , people found and make something new all the time , everything goes and grows up and up .U cant really get step in step with all new changes and generations . who can now guarantee for how long and good will be other ,newer strenghtening option,if it will be used for hard driving , track day use or daily driving . Of course i wish and think it wouldnt be worse .
But how far u can or need to go ,to be sure , that after (later) it will not make more stress on other body construction . becouse its just strenghtening in wider way . but all this its very very difficuilt to prove as its only few here and there cars ,they all different and cant be taken into comparison .and it might need years to see the progress .
And now last comparison , the cracks on M3 can appear from very low mileage , from 50k, for sure in my experience ,and can go worst by time and mileage .
Now have E46 M3 with 160k mls .usual most manual BMW gearboxes has some rear seal leaks , this one still dry as would be super low mileage . The E46 M3 diffs can be sweaping - leaking differencial from very low mileage , this one with 160k mls dry as the gearbox . even the side shaft play is so minimal . Maybe it was already replaced ,but it looks alll so original ,everything is so clean and dry ,only very rusty bolts all around the car ,as non of them would be ever touched .
And now ,finally, floor condition , it has so minimal cracks ,as cars with 70k or less mls could have .So in my opinnion its most related to driving style ! either its city driving , gears up and down, worn parts and bushes ,and long motorway driving .Have done 318i E46 with quite bad crack, have done E36 320i with fully broken out two subframe fiting points ,becouse the guy was kicking clutch on most gear changes .Have done E46 320d 136BHP , very badly cracked,same as E36 one,with destroyed two most common fitting points .And have seen a lot of E46 with different engines and cracked floors ,and they all crack in same places as E46 M3 ones crack.Its just factory faulty made chassis construction ,no blame for the engine power !
The gerabox in this 160k mls car, is still so smooth and perfect , the engine still pulls really well ,so i just dont want to argue with some
people when they rang for engine ,they want and need it ,but becouse of mileage they say they dont want to pay asking price . But how to explain and change their thinking , that any cars engine can broke on any mileage . its same as to think that all dogs bites !
Happy motoring !
BTW i didnt made or engineered these plates , its only somebodies hard done work .Like Turner motorsport or Redish plates. I only fit them as they there made and engineered to be fitted . we charge what ever we think it cost our time ,quality and labour .If would need to do as other forum member has done , it would be for sure much more expencive .Even now not all poeple wants to spend this ammount of money for this job,as some garages offer much cheaper work, but again no idea how it will be done as they not ussing Redish plates,just some welding job.Plus there is more different options to strenghtening this ,as special made cages to strenghtening subframe mountings connecting to rear shock top mounts and it work as rear strut brace as well .
Yep, I had an e46 320d in the distant past that started knocking and was well on it's way to cracking bad when we parted company, after that I went with E39's. That said if I had an E46 M3 (that I cherished and that's a distinct possibility) I'd want the best possible job done I could get, coupled with having an interest in the engineering behind that fix. Not everyone wants the "best engineered fix" some people are happy with an "It'll do" job, and as Valda's points out if he or any other garage had to do what schooner did it would cost a fortune, probably be uneconomical to do.
But for guys who DIY, can weld, grind, fabricate - Schooner's way / his link - would be how I'd approach it. If I didn't know a spanner from a hammer I'd get the best reputed garage to do a standard fix reddish / turner etc, but in general it seems that they all need some attention - if a 318 can crack a bad design, chance are an M3 will too, especially if it's driven as it was intended to.
I don't think it would be that expensive for a shop to do if they have done it once and got some experience doing it.
The materials are cheap. You could probably get all the materials for the same price as reddish plates. You will need custom made bolts.
Im sure someone in Ireland will offer this method soon enough.
Regarding plates I can't stress enough how important it is too also cut open a small window behind the rear seats and at the minimum re weld that upper portion of the front mounts. I don't think single m3 exists ( or non M) that is not failing at this point. As far as i am concerned any "repaired" m3 in Ireland is still in trouble at this location and a handful of others.
Any one notice that BMW must have learnt from this mistake because when you compare the subframe mounting points in an e46 to an E9x we can clearly see that they moved the mounting points directly under the rear chassis legs to avoid this same issue re occurring. There for the forces can be absorbed and dissipated to a stronger structure. This is how the e46 should have been and what the repair I did intends to mimic.
It's easily X2 the labour though schooner
Of course it is !Quote:
Originally Posted by 318is-joe
Some people doing job for them self don't understand that garage doing same job takes and gives responsibility on the job they do ! The time it takes to do ,difficulties of the job and so on .
Plus in my big enough experience ,people who are not really in mechanic cloths ,very often do the job not properly and can make things worst ,and to fix after will cost more as to do first time !
I'm not trying to say that schooner (sorry if bad spelling ) could do something wrong ,just I'm saying what is reality . And after a lot of examples I'm aware to buy car which was repaired by some owner who's not mechanic . That's why I don't take or do the job even on my own car if I'm not sure I can do the job 100% .
And again ,who will want to spend few grands more if that car is not keeper ,I'm sure 99% are not keepers ! And who will be willing to pay that extra ,buying that car ,as lot buyers could be who not interested in this ,at least it's not broken on purchase date . Of course I would like to do any job like this if there woul be interest .probably would like to do first for my own car if I would have it .
I would like to see this particular method become the norm for the chassis reinforcement of the e46 m3.
Someday someone will do it a few times and be comfortable to be able to offer this a good cost.
If anyone has any technical questions or wants any tips then feel free to pm me.
Quote:
Originally Posted by schoonerm3
Until peoples M3s will start to fail with plates on a regular basis this method wont become a norm.
They are failing!. People just haven't a clue about where to look.Quote:
Originally Posted by SmokyMo
I invite anyone with a repaired m3 for a totally free racp health check. I will put it on the lift and show exactly what's happening.
U have seen the one with reddish plates on and after cracked out side again ?Quote:
Originally Posted by schoonerm3
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The upper layer of the front mounts valdas. This is what I have been talking about for the last year. The beginning of the chassis failure is the upper portion of the front mounts. When you see and "fix" the outer skin you are only addressing the cracking that is a result of a failure on the inside that no one has bothered to fix
I thing it's quite good strengthening with plates from out side . If it's very bad I open from interior side and do weld .have opened the one with only rear LH mounting damaged ,as these crack first ,and front RH was perfect .so i think it don't need so extra cutting and welding as it will not make so lot changes ,as any weld is no good for steel anyway ! Non stuff and paint will help to stop later rust or other damage . The only thing to weld the plates ,is to strengthening the shity floor . It probably wouldn't be my cup of tee ,to keep E46 and know it had it's fully rewelded rear floor . It's not the case to make car be perfect forever .it will start rust in other places ,as they do start ,seen quite few .so does it worth to do all this just for your peace of mind for few years? And I'm sure ,and I have examples ,they do good mileages even without plates ! If u so scare about this type of car ,probably better just to go away ! Better I'll change the chain on N47 and will know that it will drive perfect again ,and body still be perfect,which is so difficult to sort ,rust ,paint quality and so on.and we know u got all this shite on your own skin . So how many people would go your route ??? Don't need to try and say how good I have done for my own car and how all others around Ireland and all UK now are peace of shite!! Becouse it does sounds like this ! U might say this after few years when would be what to compare ,and still there is no fully same cars to do this .thats all I wanted to say .
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I do understand what you are saying valdas. Your perfectly correct in saying that it is not economically sensible unless the car is a keeper. .
Difference is my car is a keeper and it truly get a no expense spared attitude.
Back to the actual repair conversation.. The day I see pictures of an e46 m3 upper front mount undamaged (cracked) I will eat my words
Never say never !
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If you have pics please show. Would be very useful and interesting for the community.
This thread is going a little off the topic, but hey - it's super to see a bit of passion and a lot of thought going into the subject. This is often hard to find in Ireland sadly.
The nub of the matter is that we all know the floors are a weak point, for some people buying a "fixed" car would be acceptable as they may or may not keep it long, and they may or may not give a toss whether it was fixed or not and will drive it until it falls apart.
Then there are those that are bonded to their E46 like their first born - for them how it is fixed and sealed / primed / undersealed is very important, also if you can fix yourself it's worth going above and beyond the norm to 1, give you the peace of mind you did everything you could to maintain your machine, and 2, - contribute that knowledge back to the people who actually have a genuine interest (forum users typically)
So I don't think its fair to say that the standard repair (plates only) is a crap job, not that anyone did - it probably is good enough in the majority of cases and is economically viable. If it was my E46 M3 and was a keeper - i'd be doing a bit more though.
Anyway, I've been in E39's for 15 years - I want an E39 M5 - the S62 has been calling to me for years now, waking me at night like a teenager finding the bed wet. I probably won't have this issue - but if I did, and I have the skills, and the car was a "keeper" - I'd go all out like schooner.
No right or wrong way here, it all just depends.
Plates are redundant now as total fix. As time moved on things developed and were improved. Other areas were discovered that are now considered higher stress points. How one can say plates are enough when they don't have any role in what caused the cracks in the first place is beyond me. As I keep saying. The cracks that we try to fix with plates only occur because something much bigger is happening in the background. And that's what should be addressed first. Then add your plates to reinforce the previously weakened metal. Please read the link below.
http://www.m3forum.net/m3forum/showthread.php?t=555302
In saying all the above, if people are happy with just having plates then great but I think everyone should be informed of the bigger picture and that plates will not reverse or stop the damage of the other high stress points that keep getting ignored. And if they are still happy then at least they were informed when something goes wrong in the future and they come on here looking for advice. And that's what my posts intend to do.
It's like the Shannon river when its at full capacity. People can keep putting their sandbags down to try stop the water entering their homes. This slows the damage and moves the water to the next weakest link.
(Sandbags = steel plates)
Unless something is done upstream to relieve the river of its load them we will keep having problems in surrounding areas albeit we can slow them down with sandbags.
This something can be anything from strategic seam welds in well located areas to mimic what a brace would do.
It can be a brace alone such as the Vince brace or the mason brace, it can be a combo of both brace and weld. It can be a roll cage with a subframe pickup.!
Anything that will relieve the entire panel will work.