Used E92 M3 for trackdays - how much of stock parts would need replacement?

[Shodan]

Hey guys,
I'm new to the forums. Have a '08 335i, been to a couple track days on it, and am thinking about upgrading to an '08 M3.
In my price range (up to about $30k) - I found some M3s with 55-70k miles on the dash. My 335i has only 43k miles.

Main purpose of getting the M3 is that most drivetrain, and suspension parts in it are on a different level than on the 335i. I test drove one and can say the shifting is waay quicker (the shifter in the newer 335i just feels clunky after an M3), and the suspension is waay stiffer.

But - if the M3 has 60k+ miles on it - how long will it take till I need to replace those parts anyway? Assuming the previous driver didn't track or abuse the car like I intend to

Specifically:
1) How much of the factory LSD on the M3 is left after 60k miles of normal driving? I read the LSD doesn't last that long, but most people "normal drivers" wouldn't know even when it's totally gone and effectively an open diff. ?
2) Ditto for suspension?
2.1) If the struts are on their way - on the 335i I'd replace with some aftermarket (Dinan suspension... ok maybe H&R) - but on the M3... Is there really anything better than OEM M3 parts?

Basically - how much of all the components that make the M3 so much better than a 335i - will be worn out by 60k miles to the point that they need to be replaced?

Thanks!

[admranger]

Might want to post this in the track forum...

[jaehshim]

It's been well diluted with some bs M models and M performance CF carbon parts and stickers recently, and a lot people when they purchase an M3, the first thing they do is trying to change suspension, lowered, bigger wheels, bbk, exhaust etc...even before they really try out the car as a stock form on an aggressive driving roads (Track).

The M3 in reality WAS mechanically designed with frequent track days in mind.

About the LSD, I never heard of that, even from ppl who's frequently tracking E9X M3...
if it goes bad after 60K miles, it shouldn't be a mass produced car. This is not a formula 1 car. People happily track M cars with stock M lsd for well over 150K miles.

Suspension, same story, this ain't no B7 RS4 or any other unreliable suspesion set-up car. It will last a long time.
Yes if you want to track drive an Accord or a 335i, you might wanna change the suspension, but M3 is capable on track as it is.
I say try out the stock ones first on the track, honestly I don't think it should be changed right away, as the OEM ones are good enough for amateur or pro drivers to drive on track.
If more aggressive setting is desired, there's tons of suspension setups available (all over the price range)

One thing though, changing the pads + fresh oil change is always a big plus for track days. Even a higher end sports cars require a fresh track pads for track days, as the condition of track driving is simply different from everyday driving.

As long as the car is well taken care of mechanically, try out the car as it is first, since the car stock is a very capable track tool, and the parts for M3 isn't cheap as you know. The M division and BMW R&D spent $$$$$ designing a car that is good on track, simply installing aftermarket parts + more expensive parts don't make a car drive better/faster.
You will be surprised at how good the stock is, and may regret spending so much money on parts and not being that much different from the oem.

[elim11]

You've probably thought of this already but the consumables on the M will be exponentially higher than the 335. Especially if you track. I know your budget is 30k. But I would save a lot more for repair budget/consumables especially if you want to track. As you know things wear down and add up quick.

One thing I would replace is rod bearings. It's cheap insurance against your engine , esp if you want to track it. 3k vs 15k+

[Solo_M_Tech]

Rod bearings. Don't worry about the rest of it. Just do the rod bearings as soon as you buy it and you won't have any problems. I bought mine with 89k miles and did the rod bearings 12 days later.

[dparm]

Originally Posted by Shodan

Specifically:
1) How much of the factory LSD on the M3 is left after 60k miles of normal driving? I read the LSD doesn't last that long, but most people "normal drivers" wouldn't know even when it's totally gone and effectively an open diff. ?
2) Ditto for suspension?
2.1) If the struts are on their way - on the 335i I'd replace with some aftermarket (Dinan suspension... ok maybe H&R) - but on the M3... Is there really anything better than OEM M3 parts?

Basically - how much of all the components that make the M3 so much better than a 335i - will be worn out by 60k miles to the point that they need to be replaced?

Thanks!

The "LSDs are basically open diffs at 60k" is such a fucking meme. Unless you are beating the shit out of the car at every stop light every day, the LSD is good for well over 60k.

I will be totally honest: my M3 sedan is pushing 70k and is on all original parts save for a BBK since I do take it to the track 8-10 times per summer. It just went in for the big 60k inspection at the dealer and they didn't identify any bushings or other parts as needing replacement, nor does it creak/rattle/bounce over bumps. These cars are built to be driven hard.

Some parts may need replacement at 60k depending on how old they are or the conditions the car was driven in. A car that saw 95% urban streets full of potholes might have a few bushings that need replacement, but it's not like you need to budget another 5 grand and two weeks of time to completely replace everything unless the car is already in rough shape -- and in that case, I would just look for a better car. I would obviously budget for things like brakes and tires to wear out faster, but that's about it.

There is a decent aftermarket, yes. I bought an M3 because it is just so dialed-in from the factory. I have done the whole modding thing and it just wore me out. I can drive the M3 to the track, have a blast, then drive it home -- without sinking thousands into a suspension, worrying about making adjustments, warranty coverage, etc. I know that mods would make it even better, but the car is great in stock form.

I don't know what your track experience is, but I'm of the opinion that money should go towards improving technique before anything else (the exception being safety, but don't go nuts and think that "everything is safety related, technically"). Once you've reached the car's limits, then you can start upgrading stuff.

[Wilsel]

The only parts I've replaced are brake fluid/pads, and tires (after 4 or 5 trackdays).

[ec_E92]

From experience... Upgrade diff bushings to poly. I had my diff input bearing go bad at 72k.

Basic track prep, replace as much rubber with solid/poly as possible if willing to accept added NVH.

Rear subframe mounts are supposedly huge improvement in tidying up rear.

Front sway and springs are good way to easily improve handling for low cost.

Don't know your experience level but stock brakes are good, just get got track pads (pfc or carbotech), fluid and lines.

Side note, I started tracking my DD m3 back in 2010 and bought an e36 m3 for track duty in 2014. Cost and risk is minimized and fun is maximized, I'm becoming much quicker as driver skill improves as I'm able to find the limit more consistently without fear of having a bad year. Just my own personal tolerance to financial risk.

[Jive]

Originally Posted by dparm

I don't know what your track experience is, but I'm of the opinion that money should go towards improving technique before anything else (the exception being safety, but don't go nuts and think that "everything is safety related, technically"). Once you've reached the car's limits, then you can start upgrading stuff.

This x10. Depending on your track experience, in stock form, the car has a far higher performance limit than amateurs will be comfortable with.

[redpriest]

Let me give you a run down of the stuff I've replaced on my car as a result of heavy tracking in one year (40 track days in about 14 months). My car is 148k miles, I've put 108k miles on this car personally in the last 2 1/2 years.

* Oil changes every 3-4 track days, or 5000 miles, whichever comes first, using Castrol TWS 10w-60
* Motor mounts at 100k miles - they were toast, you should inspect this every 50k miles or so
* VANOS chain guide tensioner - broke at 110k miles, this sounded really bad at idle, like a hammer to the inside of the block.
* Replaced sparkplugs at 115k miles (Didn't need to, was being preemptive)
* DCT transmission flush at 130k miles or so (last time was 60k miles due to leaky gaskets). Was replacing DCT transmission cooler with a do88 cooler, so I figured I might as well. Using Motul DCT fluid instead of Pentosin.
* Replaced engine coolant temperature sensor 2x (track induced failure, there is a TSB to repair this)
* Just replaced coil packs/sparkplugs at 148k miles (had misfires related to this).
* Battery cable is flakey (I haven't bothered to repair this yet, tapping on the DME wakes the car up when it doesn't wake up on its own, see my thread on this issue ><)

I replaced the power steering pulley with an underdrive pulley, due to my mods. I've replaced the radiator, oil cooler, and DCT cooler due to modding and the fact that I was pushing the car hard, and I needed upgraded cooling in 100-110 deg summer track weather here in CA.

Looks like my lower control arm bushings are going bad now, so I'm going to have to replace this soon as well.

I have not replaced the diff, nor have I changed the fluid since I've owned the car. It's had the break-in fluid changed and that's it. Diff is holding up fine, and it's not making funny noises yet....

[redpriest]

Oh I should mention I'm still on stock dampers, and they're not leaking or blown yet. I changed the springs to try to get some better grip through corners, and added camber plates so I don't blow through as many front tires.

[dparm]

Originally Posted by redpriest

Let me give you a run down of the stuff I've replaced on my car as a result of heavy tracking in one year (40 track days in about 14 months). My car is 148k miles, I've put 108k miles on this car personally in the last 2 1/2 years.

Big list, but honestly, with over 100k some of that stuff would've probably needed replacement sooner or later anyway. Maintenance intervals will tighten up with track use, absolutely.

[doogee]

Just to add to the differential talk. With my M3 at 100K, I find the inside wheel spinning up quite a bit on tighter radius corners.

Very irritating. These diffs indeed do not last long at all.