Rebuilding and Modifying a $4000 BMW E46 M3 - Part 17 - Cracked Subframe Here's How You Fix It

A Cracked rear subframe is very common on the BMW E46 M3 but with our full DIY step by step guide you too can fix the issue and never worry about it again.
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[@seandonaldson5084]

I'm starting to think buying a well-worn E46 isn't a bad idea....

[@thomaskovac8383]

Hard to say... I'd imagine they are close to 10-12k USD (retail) just in parts to fix this old girl up.

[@seandonaldson5084]

@@thomaskovac8383 Restoring or track prepping any car cost that kind of money. This is a modern classic with a cult following, so a well-sorted example will hold its value and go up over time.

[@thomaskovac8383]

@@seandonaldson5084 I'm not saying you're wrong but I just wonder if the average enthusiast could save money buying a less needy example versus spending so much to revive such a high mileage car.

[@seandonaldson5084]

@@thomaskovac8383 Well a lot of the work they have done would need to be completed on even the most spotless example. Rod bearings, Vanos gear, and subframe reinforcement are all must do items if your going to do anything but put it in your garage and rub it with a diaper.

[@cyanframe]

Nice Video! I wish i could fix my e46 here in Germany like this, but sadly we have TÜV who says no unless you have a welding certificate or you get someone with a certificate to Weld it for almost the price of a cheap e46 😂😂😂

[@therealpofo]

Next time you should use a weld thru primer, so you dont get corrosion on in between the layers

[@becomematrix]

Shane Massa my thoughts exactly

[@Ciernik93]

and make continous weld not points. This point welding in trunk and covering in silicon. Pain to eyes...

[@TheFoxSaid]

Man, I remember my 1st time with a welder. Pro tip: Drill out each end of your crack and grind into the crack for full pen weld

[@valdipietro]

Welding around the fuel tank. Brave.

[@mrmidnight32]

I love you guys have sponsors. I can’t stand when other channels who do KZbin and videos just for money and profit. But when guys who are actually passionate about things get sponsors like you guys it always makes me happy! 👍

[@BobPegram]

Advantage of running an older car: people know all its weak points and devise fixes for them.

[@mas921]

You guys are BMW believers! I really hope/look forward to, after all this hard work you guys would have fun drifting this. I would've gave up months ago lol

[@Bimmer2047]

I've seen guys go as far as cutting all the top sheet metal between the rear shock towers inside the trunk and lay in a 2x4 0.120 wall box tubing spanning from shock tower to shock tower. and seam welding it to that inner structure where you welded those spot welds. then they weld in a strut tower brace. and triangulate it to the box tubing. ULTIMATE STIFFNESS!!!!

[@friguy4444]

Yea there's a kit from a small company called "Mason" I think their from the Netherlands but not sure. They make the cross member and Shock mount unit you are talking about. Then there's also the "Vince Bar" which cuts the whole floor from the shock to shock at the spare wheel well. Some people do Both of these and it is considered the "Ultimate" E46 subframe fix assembly. Apparently you can put the bar in along with the cutting and assembly without actually welding. Then there are the real paranoid folks that do all three. (The plates, Mason cross bars and Vince bar lol). But it's way, way over kill. I've done just the plates and whats known as "Foam" Which was BMW's first plan of prevention. But that's a whole different story. My rear is as solid as ....well put it this way i can jack the whole car up with two jack points because it's so stiff lol. Here's a two part video putting in the "Vince Bar" Part one: kzbin.info/www/bejne/d6LQq3iklpqlqK8

[@Jury1111111111]

I too went for that solution.

[@JVR_Funwithdesign]

Ah yes, the 'foam'. Because of course you can fix weak structural sheet metal rigidity with some foam. :)

[@gregpetroski6333]

i've done this job before with a buddy in his garage with no hoist... We built an e46 rallycross car! It was definitely unpleasant but overall not a terrible experience. Everything is well documented and pretty easy to follow. We ended up bracing the trunk area a bunch more just to ensure it can take a beating from jumps and whatnot.

[@secondpsyght1354]

Quick question for you. PMC Motorsports has a short shifter for our vehicles. They recommend bracing the transmission to the body when fitting their short shifter. Now the question. Considering your efforts of bracing, did you brace up your transmission? Going to your channel as I type this... By the way, zf 5 speed trans here. Behind a m54 2.2l in a facelift 320i touring.

[@ianlancastersaunders5447]

Nice to see you kept the petrol tank. There . Are you suicidal ? Professional guys at work 😂

[@ruinman8722]

Thank you for this series guys! I was thinking about getting an E46, but you convinced me to never do such a big mistake!

[@Rokynutz]

Literally did this fix on my buddies 46 last weekend. Lol 😂 I wish he had looked up this kit. I did it the old fashion way. Lol remove seat and truck area, cut out torn crap metal, fab and weld. Lol

[@bdub03]

Thanks for covering the trunk weld job. Bimmerworld did not include any photos in their kit of welding up the triangle. Cheers!

[@consentidocomunwithcommons7698]

I did this like 10 years ago with my e46 and worked fine after remove all gas tank and all suspension out just to soldering. I bring allignment shop and ready to go

[@yerrie1908]

My E46 Alpina B3 based on the 330i was already good reinforced but I have now the subframe installed from the 330D , transformed the car, it;'s amazing

[@BenFreedmanRacing]

Very detailed explanation of reinforcing of the subframe mounting point. Makes me thankful that I live in California

[@waclosh]

Has nothing to do with rust. They fall to pieces on bad roads everywhere. Or on good roads with bad driving.

[@BenFreedmanRacing]

waclosh I just meant working on a rusty car in general but yeah I agree

[@chrisr4815]

I'd rather deal with rust than libtards and laws for everything.

[@vosedon]

You guys should do a E39 M5 next. You would double up on subscribers for sure. Great stuff guys!

[@takeapieandrun]

Nice production quality, rare to see on this kind of vehicle related fix

[@mohammadshahin4922]

Hell yeah boys! Glad to see everything is going well. Hopefully the info I sent came in handy. Picking up my car tomorrow after subframe job is finished!

[@grumpyjuicetrucking]

No weld thru primer? Cool

[@eduki]

Remove the fuel tank! Prepare the surface with a proper rust preventive spray flux or similar. The flux chemically cleans the steel and prevents oxidation. Drill each end of cracked lines, open the gap of cracked lines a bit with a Dremel to help soldering penetration, otherwise you´re doing nothing with that superficial welding, then solder every line and the drilled ends. Apply an urethane filler on each gap of the solder and covering the soldering Paint with anti gravel spray all the area of the plates, and solderings when the urethane coat is cured. Not just simle paint Proceed with the rest of the job (sorry to say it, but the soldering is horrible)

[@altimatic2183]

A common issue from what I've heard! Thank so much for posting

[@playlistforkids]

thanks for doing this, love the BMW content

[@pFbSpecV]

man lol so much work you guys are putting into this one it seems. keep the content coming!

[@NathanGess]

Quality work guys; thanks creating this resource!

[@dongkyukim3580]

pretty brave to do this with the fuel tank in the car lol.

[@4LO4LO]

Have you seen these guys' welds? I don't think brave is the right word here.

[@fabiogranadosmendoza2178]

Good video, very informative thanks. I wonder why you didn't remove the fuel thank for the welding? All the best! Keep it up!

[@nathanielbarbeau4821]

Can’t wait to see the total $$$$$$$ spent on this masterpiece. Polishing a turd at its finest.

[@TheStwat]

They are making videos for you and me to watch and enjoy. It's not about the $$$$£££$£$£$£

[@nathanielbarbeau4821]

TheStwat aka Stuart Wright I still gave it a thumbs up there buddy. Good stuff!!

[@RickHavok]

The guy with the Miata lemon as a profile pic talking about turds! LMAO

[@Injen1us]

what a cool video! i loved the time lapse scenes

[@zachicusmaximus5551]

I did this on my back in the driveway, but on my E36. It seems to be almost the exact same process. It's definitely a more than 1 day project so don't do it on your daily if you have work in the morning.

[@briantristan5634]

Tell me about it

[@alkalineph9446]

This is one trade I want to learn.

[@DJzSith]

Speed Academy laying down that hot bead of pigeon droppings :))

[@James01234]

Should have drilled a hole at the ends of the cracks to stop them continuing

[@KXP70]

Can you explain the process in more detail please

[@goldenhide]

Basic metalworking is all: a crack is just shearing force along a "fault line" in the metal. The line continues and causes metal ahead to stress and weaken and the crack continues on. Stop drilling the crack spreads that weakening ahead of the crack into a larger surface area, lessening the radius and stress being applied; lessening the chance of it continuing. Granted, you still need to actually do a repair over that for longevity, but it works. As for size, I was taught in aviation that the smallest enough size to do the job is necessary. But, it appears some engineering papers have been written and they recommend going relatively large as it narrows the crack radius to almost 0, practically killing the metal stress.

[@stektirade]

yuup thats what you are supposed to do.

[@Retrobeemer]

Hi from 🇬🇧 and thanks for giving valuable insight into what’s really involved with owning and properly maintaining an E46 M3. I’ve just done this same job but included a weld in rear brace from Safety Devices. Also replaced brake lines & trailing arm bushes, powder coated diff’ subframe etc too. Will you be covering your geometry set up? Anyway subbed for future. Mark 🤓

[@mart1547]

For some top tips, Redish Motorsport

[@axsb]

so far every video has a theme, we're fixing a known problem lol love this car, but this is funny. the aftermarket companies are staying in business as long as these cars are still on the road.

[@dapezent]

Pro tip: place wet rags over the plastic fuel cells before welding. You guys are lucky no weld splatter melted through which could have been an explosive situation. Good work nevertheless.

[@ejoautovideos]

E46's are super cheap here in Sweden, but this is a big reason that is holding me back from buying one.

[@e36fanatics]

the kit is like 100 euros... doing this doesnt take more than one evening but if you dont have tools or place to do this like me its a bit harder but it has to be done if youre gonna abuse the car

[@thedownshiftchannel]

Yes that is correct they are all broken!

[@Jeffe46M]

You should have got a CMP or Vince bar in addition to the underside plates to reinforce the rear subframe mounts. Plates are needed but not enough for the abuse from drifting/clutch kicking.

[@ramdaftar5180]

Nice work guys

[@Gensixvette]

I don't know what's worse, the welds or the music.

[@R0adsterr0land]

The Z was ready to go with minimal cost and prep. Meanwhile the Bimmer is already a blackhole of effort, money, & modification. Is this what people mean by superior German engineering?

[@gme0ver24]

R0adsterr0land German engineering at it’s best.

[@scoobygms210]

R0adsterr0land yes lolol

[@S1ckbg]

Im sure the bmw is much more abused from driving... nobody buys an m3 to drive is slow

[@Ryousure]

German cars are lease only. Guys that buy them are as bad as women that buy 1k bags. if you can afford to lease them and only drive 15k Miles a year. Do it and rid your self of maintenance.

[@Retrobeemer]

It’s a high performance car and needs proper maintenance. Add the fact it’s more than 15 years old and this stuff is simply common sense! Whether you’re a fan of BMW or not, these are iconic cars and epic fun to drive. Admittedly I wouldn’t want a convertible myself but still huge grin factor. 😎

[@RickHavok]

The suspension springs break, they're made from the same bad batch of metal the SMG detent spring is made from I guess, or they break when the rear CA bushing are shot, not sure which, but it's common.

[@stylerunner2959]

Proper maintenance and reinforcement is a given with any race build. Unfortunately the E46 will require a little bit more work to cover the weakness of hard driving. Preventative is key!

[@thetuningfactory1345]

Well now I want a whiskey sour, one problem I don’t drink, so instead I ask the name of this song?

[@ИванАсенов-ф7з]

Midnight Hour - By Raw

[@thetuningfactory1345]

Иван Асенов damn the KGB can even Internet better than me. 😂. Joking obviously, not sure where your from but thank you! 🙏🏻

[@m42b14]

What kind of seam sealer are you guys using? Looks like a solid product!

[@nikothecrazygreek]

You guys are canadian Im surprised you havent used any tremclad on this thing

[@antmarino9635]

Curious to know why you didn’t just lower the hoist a little bit if it was too high?

[@jacquesgold]

Digging the new tunes, great find!!! Please share the artist & details?

[@antbymcnair4297]

Yeah why all the music hate. I liked it too!

[@jwrx7tt01]

following

[@revolutionday1]

@@antbymcnair4297 .....right?!

[@AndreEST]

Awesome song, still waiting for the name :D

[@midnightg3593]

Done mine on my e36 and just makes me think how much more of a headache it would have been if I got a e46 the job looks more extensive than a e36

[@Skitzballs]

You guys are the reason I went with Fortune Auto 500's on my e36, love the content and much love from Texas!!

[@ButtKickersReviews]

Etch prime BEFORE seam sealer.

[@chrisr4815]

Would have used weld through primer.

[@JVR_Funwithdesign]

Broken e46 rear springs is a pretty common thing. Both my touring and sedan had this issue. The paint flakes and the rust weakens them.

[@erikthie2253]

Nice Touareg!!! Is it a TDI? Doing anything with it?

[@therealboofighter]

I was thinking the same. Go flames!

[@erikthie2253]

@@therealboofighter still no reply... :(

[@therealboofighter]

erik thiessen probably nothing going on. Just brought it in out of the cold.

[@erikthie2253]

@@therealboofighter I have a 2013 TDI Touareg in Alberta. It stays in the garage when not in use. The cold here is extreme!!!

[@therealboofighter]

erik thiessen I live in Alberta as well.

[@jakethesnake1503]

The game is on

[@gregggilbert]

Always blamed the snapped rear springs on both my e46s on the crap roads around here, but starting to think its a thing. Never got the problem with the eibachs at least.

[@jamesashe]

Midnight hour. Whiskey sour.

[@vVeazel]

Could you guys make an episode on the Touareg? How reliable has it been?

[@speedacademy]

Videos are coming on it in about 2-3 weeks!

[@5050Design]

Still can't believe you guys arent doing headers...

[@M3nace46]

Broken rear springs are common for E46s and other E chassis models

[@jacquesgold]

I see lots of BMW haters her... Logically it doesnt make sense. Its similar to the logic behind an Alfa. But when you drive it, oh yes, it all makes sense & nothing else matters.......

[@mro9466]

you can hate the fuel consumption, the high level of maintenance, the price of the parts ... but at the end of the day, few cars bring this much driving pleasure for that price ...

[@bsouza1675]

Great vid 👍. Thanks

[@djjmann]

The reason I sold both of my E46 M3's. Both were in pristine condition, no sub frame cracks. But the long-term commitment to keeping those cars running...its pretty annoying. Especially the SMG system, which isn't that expensive to fix, its just tedious. I would buy another E36 M3 all day long over an E46 (which I owned two of those as well). I've graduated to an SRT Grand Cherokee, its faster than the M3, more space, and maintenance is pennies on the dollar of the E46 M3. #daddymobile But aside from this, great to see so many tutorials out there on how to do the repair correctly. I'm afraid there may be a glut of "shade tree mechanic" patched sub frames rolling around that are destined to fail catastrophically.

[@Rokynutz]

Oh...Dave, explain the coke and break line setup. People would go nuts for that.

[@I.Odnamra]

When your bushings start to squeak, just spray some silicone lube on them. 👍 Mainly on the CAB and RTAB

[@nicolasbenoit6753]

PT has a RWD car with a cracked rear subframe? anyone else having deja vu?

[@boomboombeach404]

not afraid to weld next to the gas tank??

[@bransonfleischman2233]

Look at it this way: either you get it done faster or maybe, if you are lucky, your BMW burns to the ground and prevents you from spending any more money on it.

[@Regmou5]

@@bransonfleischman2233 its a win win

[@Anthraxegott]

Broken rear springs are a common issue on BMW's . Snapped 3 myself, under the ownership of two different cars. Ended up buying constant diameter springs, and it hasn't broken since then.

[@heinz490]

front springs breaks on e32 e34 but rear springs last forever

[@Anthraxegott]

They tend to eat a lot of front dampeners too. Would still like to own a E34 some day, but almost all have ended up at the scrapyard by now, sadly.

[@heinz490]

@@Anthraxegott i had a e34 from 89 with a m20 engine but i found a m50 engine and that did the different i loved that car sorry that i sold it the e34 and e32 was made to last

[@Anthraxegott]

A friend of mine´s first car was a ´89 520i and it was underpowered like hell but we had a few good adventures in it. He later ended up with a E28 M535 with a 3.6 S38 that was just ridiculous.

[@TheStwat]

Shirley you treat and spray the welds before using seam sealer on them? They will just be rusting under that sealer.

[@laynerichardson4913]

great song

[@pablogagne488]

Nice video

[@arekb5951]

Yeah, post 2000 BMWs aren't the best when it comes to build quality and reliability. But when they work they're really fun.

[@karltaht2370]

e36 had this issue as well :(

[@juicewrldclips6523]

I ordered e46 reinforcement planted and some of them are different shapes???

[@silys5253]

Protip for the „pros“... you got lots of spot welds that connect the sheet metals which are rusting... which means they have popped. should have drillep them out and plug-welded them. people still dont get it. these spot-welds are the reason why the subframe drops, moves and cracks. these should always be welded to prevent further movement, dropping and cracking of the subframe

[@goodfella4766]

So about how long did this take? A estimate please ... I

[@simonhill6267]

Should drill the end of the cracks before welding... Ideally

[@AllTheBestNames]

Thumbs up from me but I'm getting burnt out on all the BMW stuff, been there done that and I knew it was gonna be a drawn out process when yall announced the M3.

[@simeonpallatt3567]

What is the song playing during the time-lapse

[@LoudGuitar14]

7:24 Someone is in timeout back there

[@TheTempest909]

Make the music stoppppp

[@Oborowatabinostk]

Yea too much

[@alcubano2887]

It's so bad.

[@anenglishmaninbrazil3212]

The same cracking problem was on the earlier 3 series as well

[@russelledbetter1726]

I had heard of this problem on the E36 but when I dropped subframe on my 1999 M3 reinforcement plates where already there. Looked factory.

[@xorpgorp]

I have a question I'm sure millions of people have also asked; why don't manufacturers make all components of the brake lines, and bleeder screws , etc out of stainless steel?

[@anders949494]

cost

[@m3g670]

hard to say this but i got the same car and have no idea if the subframe is good or bad but defenetly im almoast ready to order those plates and sinse i have welding equipment and skills to do it myself i will do it soon for shure it will be a loooot of fun doing this 😂😂😂😂😂😂😂😂 and for sll of these guys that havent drive an m3 i think better dont even think abouth it since you are scared to have a legend of a car that is awesome to drve,fun to drift, perfect for tracks (save your money for prius ) Good things arent cheap 😎

[@secondpsyght1354]

Too right, fruit that grows overnight doesn't exist for good reason.

[@Vgk36]

oo oooo so much nastiness !! hahahahahaha. you guys and your subliminal messages lol :)

[@samjohns513]

plates aren't gonna cut it lol how do you guys have this channel I haven't seen anything past basic bolt on work done badly

[@igorgrebenevich428]

what is the black stuff spread over the welds?

[@LaloFoSho]

does it matter what type of welding you do

[@TomH112]

Should have drilled the ends of the cracks so they stop continuing before welding.

[@RobertKohut]

Nice!!

[@Dutch94]

Why do guys with the best tools always make a hack of it

[@cameronowen5601]

I did this with an Audi A6 wagon

[@StoicBroic]

how much would this cost???

[@therealboofighter]

Dropping a subframe? Is this TommyFyeah? Lol.

[@phillipsalisbury1385]

You should have welded a Vince bar in there.

[@adamhowe9349]

I guess I won't be getting an e46 :(

[@scoobygms210]

Adam Howe as a mechanic I don’t recommend anything German but Porsche ha

[@grecoconduris6716]

Whilst I’ve always liked the E46. If this much work is involved I think I would prefer to do it too an E30 and insert Japanese engine.

[@scudd05dl]

If only I knew before lol

[@joem3713]

Honestly man to me the e46 is one of the easiest cars for me to work on. Dont know why people make it out to be so difficult

[@e36fanatics]

@@joem3713 have to agree... this isnt even that tedious of a thing to do compared to some others...

[@ИванАсенов-ф7з]

Great video. Anyone knows the name of the song?

[@AndreEST]

Also would like to know the name of this song!

[@ИванАсенов-ф7з]

@@AndreEST Finally found it, Midnight Hour - By Raw

[@Kit2Kay]

what type of welder was used in this job

[@speedacademy]

A Miller 110V MIG welder

[@Kit2Kay]

@@speedacademy would it be possible to cut into the three spotwells and then use epoxy glue to join them with the metal directly under them if you don't have access to a welder

[@matthewcheung6062]

why did you guys deleted the 200 tw tire test.....

[@speedacademy]

Uploaded the wrong video. Today is the 100 tw video. It just uploaded.