Rather extensive drivetrain/suspension refresh

[IamFODI]

EDIT: Driving impressions on post #25!


Follow-up from this thread: https://nam3forum.com/forums/forum/e...ension-service

After some delays, work has finally started – though it has had to be split up into two stages. Here's what's getting done right now:

- Clutch kit (OE LuK)
- Flywheel(OE LuK)
- Driveshaft (BMW)
- Differential (Diffsonline – 100% stock spec)
- Autosolutions shift kit (+40mm extended lever, 15% throw reduction)
- All bushings in rear subframe (Bimmerworld solid subframe mounts; all else OE)
- All rear suspension arms & bushings/balljoints (OE BMW/TRW/Lemförder etc.)
- Rear ARB end links (SPL)
- Rear ARB bushings (OE)
- Less-old stock muffler
- Re-grease & re-boot rear CVs
- Rear main seal
- Trans output shaft seal
- Shift shaft seal
- Rear subframe powdercoating
- POR-15 on rusted areas
- Rear O2 sensors
- RL wheel bearing
- E-brake rebuild (shoes, cables, hardware)
- Trans tunnel & muffler heat shields
- Some repair/replacement of old fasteners, studs, etc.
- 513M wheels, stock 245/265 tire sizes


Also planned, but delayed because Bosch apparently can't decide if/when it'll build steering racks:

- Steering rack (new Bosch)
- Steering rack boot
- Front wishbones (OE TRW)
- Front ARB bushings
- PSF reservoir
- Engine mounts (Corteco)


After I get the car back on the road, I'll do my best to offer useful commentary about how it drives. But at that point it'll have been 2 months since I've driven the car at all, so anything I say will have to be taken with a grain of salt.

Also I'm terrible about taking pics and the car isn't with me, but I'll post what I can.

[IamFODI]

Parts boxes stashed in/near a parts car – virtually all is for the M3, and not everything is in the pics:

[IamFODI]

Timing on some things didn't quite work out. The diff had to be pulled and sent back as a core to Diffsonline before the rest of the work could proceed, so the car ended up being partially disassembled and then put back on the ground to free up the lift.

[IamFODI]

Custom Autosolutions shifter lever next to a stock one.



I almost never see an aftermarket mod I like – let alone one from a tiny operation. An Autosolutions shift kit is one I've been positively salivating over since experiencing their kits in E46s. I've been looking forward to this for a while.

I wanted a longer lever so that the knob could be closer to the steering wheel. But I also didn't want to mess around with non-stock boots and knobs, either accepting a slapdash look or spending more time and money getting it right with a custom solution. So, I compromised by shooting for the longest possible lever that'd let me keep the stock knob/boot.

To estimate how much longer the lever could be, I took the original knob off, set it down gently on the lever, clipped the boot back in, rowed the gears to make sure there was enough slack in the boot in all relevant directions, and then measured how much higher than stock the knob was sitting. Those crude measurements suggested the stock boot could accommodate a knob height that was at most +50mm from stock. That's probably a slight underestimate as my method effectively added to the throw length (same shifter assembly but the knob is sitting farther from the pivot); the shift kit would bring the throw length back to stock or less, leaving more slack in the boot, so there'd be a bit of margin. Still, I thought it made sense not to ask for anything close to what I thought was the limit, so I requested +40mm.

I had originally asked for stock throw length at the new knob height. Ronald at AS felt strongly that a slight reduction was necessary to get the best out of the kit. He obviously knows better than I do, so I went with his suggestion. This means even more margin for error on the lever length. If there turns out to be a bunch of slack in the boot with this setup, I'm sure I'll wish I had gone +50mm. But that's a better outcome than the opposite (lever being too long and knob/boot not fitting).

There are multiple options for the forward carrier bushings. I opted for the hardest of them. Ronald advised me that there might be more perceptible NVH. We'll see.

Ronald accepted this as a unique project with the understanding that we were both venturing into the unknown. It'll be interesting to see how it turns out.

[Obioban]

Paper walls in a garage would never work for me :P

Car should feel great after this!

[Sharocks]

OP someone nabbed your engine.

IDK if you knew LOL

Ron is one of the best folks I've worked with in my entire car phase.

He knows what he's doing which is why I have his kit in pretty much every car I have.

[IamFODI]

Trans out:





Obviously leaking. It's had an output shaft seal weep since I bought it, and more recently we thought the shift shaft seal was leaking as well, so we're replacing both. But this looks like it could be more, no?

AFAICT, that sensor up top just sits there on the trans and doesn't penetrate the case, so that's not it.

Maybe the two parts of the casing? TBH, if it's that, it's gonna stay that way until it's making puddles on the floor or I sell the car. Opening the trans gives me the nopes.

Current plan is to replace the seals on the output and shifter shafts and hope that the crap elsewhere on the trans was slung up there from somewhere.

[IamFODI]

Clutch pack, flywheel, and RMS out:


Wish I had bothered to look more closely at this pic after taking it because it doesn't really show how dry the area around the RMS was. All that crap around it is clutch dust. The RMS – original, >156k miles – was perfect.

We replaced it anyway, of course. I'll be so, so mad if it leaks.

[IamFODI]

Finally getting to the point where we're installing new parts rather than just disassembling! Flywheel and clutch pack in:

[IamFODI]

Car should feel great after this!

Yeah, I think so.

Especially as I won't have driven the damn thing for >2 months, one of which I spent driving nothing and the other of which I spent driving the Mazda5. 🤣

Ron is one of the best folks I've worked with in my entire car phase.

He knows what he's doing which is why I have his kit in pretty much every car I have.

Yeah, he's a good dude.

Thanks for the feedback. Always nice to have confirmation.

[tdott]

Alot of work! I did a similar drive line refresh not long ago, minus the rear suspension arms.

[IamFODI]

Guide tube on the trans input shaft had seen better days:



Replaced with new, along with the TOB, clutch pivot pin, release arm, and spring:




Also replaced a rusty-AF exhaust center support plate thingy, along with the rubber mounts and nuts:




Rear subframe back from zinc coating followed by powdercoating:



She's coming together!

[Cronenberged]

Very nice, just curious what the Wesson cooking oil going on 😜

[IamFODI]

Very nice, just curious what the Wesson cooking oil going on 😜

BMW 10W-60 is expensive, bruh

[Epoustouflant]

Rear subframe back from zinc coating followed by powdercoating:



She's coming together!

That is especially nice - great touch on the zinc, should last a lifetime. It's maddening how BMW never got their steel subframe coatings right.