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.
Bimmerworld Subframe Reinforcement Kit: www.bimmerworl...
Koyo Rad: www.koyoradraci...
Spec Clutch: www.specclutch....
Support us and buy parts from our new SA Shop: www.speedacade...
Join Our KZbin Community: goo.gl/n4m3Ez
Our Patreon page: / speedacademy
Our Merchandise page: speed-academy.m...
Favorite Tools:
Astro LED Work Light: amzn.to/2r70JUu
LED Bay Shop Light: amzn.to/2HHBw9D
Milwaukee Ratchet: goo.gl/2Cvuzm
Milwaukee Impact: goo.gl/kxnJTg
Miwaukee Sawzall: goo.gl/Sbw5FC
Fluid Transfer Pump: amzn.to/2ILVP9u
Uvex Face Shield: amzn.to/2jgZttO
Astro Rivnut Tool: amzn.to/2HAZN51
Rivnuts: amzn.to/2Fse0v8
Canon 70D Camera: amzn.to/2HAQ9PT
Canon Lens: amzn.to/2HD4Pd7
Rode Microphone: amzn.to/2FsGeGa

[@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 😂😂😂

[@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

[@BobPegram]

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

[@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. :)

[@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

[@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.

[@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

[@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

[@mart1547]

For some top tips, Redish Motorsport

[@bdub03]

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

[@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. 😎

[@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! 🙏🏻

[@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.

[@ianlancastersaunders5447]

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

[@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.

[@takeapieandrun]

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

[@chrisr4815]

Would have used weld through primer.

[@thedownshiftchannel]

Yes that is correct they are all broken!

[@playlistforkids]

thanks for doing this, love the BMW content

[@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.

[@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!

[@jamesashe]

Midnight hour. Whiskey sour.

[@TheTempest909]

Make the music stoppppp

[@Oborowatabinostk]

Yea too much

[@alcubano2887]

It's so bad.

[@Injen1us]

what a cool video! i loved the time lapse scenes

[@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.

[@simonhill6267]

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

[@nicolasbenoit6753]

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

[@I.Odnamra]

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

[@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.

[@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

[@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!

[@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

[@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

[@TomH112]

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

[@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.

[@laynerichardson4913]

great song

[@bsouza1675]

Great vid 👍. Thanks

[@cameronowen5601]

I did this with an Audi A6 wagon

[@antmarino9635]

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

[@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.

[@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 🤓

[@Dutch94]

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

[@simeonpallatt3567]

What is the song playing during the time-lapse

[@pablogagne488]

Nice video

[@phillipsalisbury1385]

You should have welded a Vince bar in there.

[@juicewrldclips6523]

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

[@scoobygms210]

I’ve o my been welding for like a month and I weld better then that :/ dang he needs to spend some time on that garage practicing beautiful welder and gear tho

[@TheStwat]

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

[@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...

[@goodfella4766]

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

[@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.

[@Oborowatabinostk]

"Without further ado"

[@StoicBroic]

how much would this cost???

[@stektirade]

"we might as well do them"? you must replace the bushings period.

[@adonisbrooks2794]

Not all E 46 have that problem I have a 2000 to 330 at sports package no problem

[@LaloFoSho]

does it matter what type of welding you do

[@Assorted-Moose-Nonsense]

What is the soooooong???

[@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.

[@Vgk36]

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

[@panchonorthmann6408]

I don't want to be the angel of doom, here, but without cutting grooves into the cracks those short bursts of mig weld aren't gonna be enough penetration. Also, weld through primer...

[@Jeremy-pm3ym]

What's the song, guys?

[@igorgrebenevich428]

what is the black stuff spread over the welds?

[@vincentpoon6999]

music was wayyyyy to loud in this video. Tone it down next time fellas

[@Ellwood76]

if it was a decent song i wouldnt mind the volume....

[@danieltubbs5422]

All of the welding experts have already spoken so I'll add this, please, no more of that whiskey sour song, please.

[@PANTYEATR1]

4G welding...it's fantastic huh?

[@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

[@Projekt5.3]

jesus these welds.....whole lot of cold welds with no penetration......

[@RobertKohut]

That soundtrack!!!

[@PirataSports]

People go on about German engineering but what they really mean is manufacturing, for example this inadequately engineered turd would have been assembled very efficiently.

[@RickHavok]

So your reasoning is that the most winning car in it's class is poorly engineered, and a bad batch of metal has nothing to do with manufacturing? Pretty ack basswards there if you ask me.

[@nightmonkey07]

Great vid as usual guys. But that song was awful.

[@Andrea_eTi]

Pro tip (from a real Pro) : when you have a rusty brake line put heat on it.

[@therealboofighter]

Dropping a subframe? Is this TommyFyeah? Lol.

[@tobycosford1]

Did Pete just complain about having a hoist? lol

[@Fordman7575]

First world problems!

[@djsonicc]

doesn't look too bad to do at home

[@wrenchoperator6435]

I've been enjoying the E46 build series so far, but guys, what's with the music?! Yuk!

[@MJTAUTOMOTIVE]

Gas Tank!

[@Ryousure]

I love these videos!! Saves us money. Note to self. Don't buy a used BMW. Bring my wallet

[@BobPegram]

Look up Joakim Karud on Sound Cloud for different music.

[@Killerconceptz]

Whiskey sour

[@fox10169]

I bet that crack repair will be rotted out in 5 years. Took all the protection off the oem metal

[@randellgribben9772]

you would think ,, spending all that money and have a bad design from the factory.. frame cracking engine failures.. wow!! and please practice your welding on some scrap steel first.. to learn how top get nice clean even weld lines

[@ΣΤΑΥΡΟΣΓΚΕΡΛΕΣ]

this shearing actually continues to this day bmw's even subcompanies like mini. endless minies coming in for front strut tower straightening because for some reason they are all bend. Rear also shearing. Terrible chassis these cars. And they also suffer from rust and corrosion. Both audi and mercedes are light years in front of this company. And what is more frustrating is this brand's denial for under warranty fix or a recall .

[@Slagtrap]

**Pro tip** Remove the gas tank/s if you're welding literally less than 1 inch from them, especially if they are plastic! Who cares if you fry the ECU leaving the battery connected if the car burns down.

[@whatthe363]

9:00 Im sorry but the song is giving me a hard time. Maybe some elevator music? Metal? Jazz? Idk that Whiskey sour shit was.......

[@Afterfire999]

I'm sure some people might have the opposite opinion but my gf and I hated the song. Maybe if it was just used once or for a shorter amount of time it would've been less noticeable but we've gotten to the point where we are annoying each other by saying it while the other is in the shower so they can't stop thinking about it. It is really terrible. Otherwise what a great episode.

[@michaelburket9024]

That song was just terrible

[@revolutionday1]

Uhmmm....why?

[@kirstysinclair9021]

I cringed watching your welding and grinding .

[@abr5819]

Is that even done? All these armchair experts talking about should have done this , or added weld thru primer , or crap welding all sat at home tossing it off saying it’s not done right spot welds blah blah like it’s supposed to be a perfect job or they could do better job or job is wrong ….which one is it !?

[@trance2012]

What is up with the music, it sucks so bad. Hochi mama singing while you work on a busted BMW ghetto machine

[@ZayedGR]

💙💙💙💙❤💙❤💙❤💙❤💙

[@ABeans07]

Ew spec clutches. Have a forever tainted view for me as the springs and rivets like to come apart.

[@Neurofunk81]

Horrible song in the background

[@Chimp_Assassin]

That song sucks

[@revolutionday1]

YOU suck.

[@TheNassiepoo]

Worst song ever! that was painful.

[@revolutionday1]

You'll be aight.

[@elijahparsons4530]

WHISKY SOOOUR

[@ardyshane23]

I would have never thought a BMW M series car would be so poorly engineered. So much for German engineering being anything to write home about.

[@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...

[@valdipietro]

Welding around the fuel tank. Brave.

[@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)