[kemwer]

Hey thread,

First off, thanks everybody for sharing experience and knowledge over the years!
I've read through previous 11 pages (and several other threads) and learned A TON in the process.

I'll split my recent experience in three parts, but before that here's a brief history of my relation with current car.

After owning 2006 e90 320d RWD for two years and falling in love with how it felt driving it, decided to upgrade to a newer f-series two and a half years ago.
Initially I was in the market for 3er (f30). Simple upgrade, wanted M sport interior and YOB to be around 2015 (not knowing at the time that it was LCI year).
Offer was limited, mostly with basic equipment, so I expended my search to f32. Since those were stretching my budget at the time (on avg. 50% more expensive compared to f30 in local market), I settled for 2015 f34 (pre-lci) 320d xDrive with just above 106k miles on the clock.
Got interior I wanted (with panorama roof included) in my favorite color combo (black with red details). Served us great for long trips across Europe during all seasons and conditions, as well as daily driver through city. No major issues, just regular maintenance in local dealership. Until two weeks ago...

Tire Change

• Summer set

  In April I wanted to upgrade my stock squared wheel setup (Bridgestone Blizzak LM001 225/55R17 tires on standard 8j et34 5x120 rims) and go with staggered setup, so I optioned for 19" rims (BBS replicas, 8.5j et35 in the front and 9.5j et40 in the back) and ContiSportContact ROF tires (225/45R19 front, 255/40R19 back). Did due diligence and researched (in this forum as well) about the fitment and experiences people had with similar setups. No issues spotted, so I went for it.
  Looked like a dream, worked like a charm!
  Roads here are a mixed bag, so I was concerned I may loos all comfort in driving, but subjective feeling didn't change a lot, comfort was still there.

• Winter set

  Three weeks ago, encouraged by previous change, and in big part blindsided by the looks, I went in search for winter tires. Wanted to have same setup, on same rims. Little did I know...
  Purchased Conti WinterContact TS 860 S XL ROF (225/40R19, 255/35R19), balanced and mounted them, and problems started as soon as I started rolling on them. Transfer Case was not having it! You could feel stutters whenever you tried to accelerate. Initially I thought it was just an issue with tire balance, went to re-do it, but it didn't help. After three days (and some exploring) I drove it back to the garage and switched back to summer tires. Problems with stuttering disappeared immediately. Went back to local dealership for a quick check, no problems found. Hit the highway for additional stress test two days later, all was good.
  Planning to switch winter setup back to squared 225/55R17 (Bridgstone Blizzak LM005 tires) since I still have to old original rims.
  

Output Flange Failure

Very next day on road to work, big "hit" happened underneath the drivers seat. Thought it was a clutch at first. Motor seemed to work fine, was able to move to D/N/R but couldn't connect gears. No leaks. No burned smells.
Transfered the car to auto-transmition expert and upon quick expection, turned out it was OF failure. I'll get my car back in next couple of days (ordered transmition oil and filter replacement as well since I have no info if it was done before) and if mechanic saved the old OF I'll take a picture of it and attach it here. Will check with him if he also replaced Guibo.

Transfer Case Recall

After I get the car back, I'm also thinking of visiting the dealership and asking about this recall and if that's 'a thing' around here.
TC gave no signs of failure previously, but since I just hit 120k miles on it, would hate to have it fail on me (like OF) unexpectedly.
Not sure if partial reparation is possible/recommendable?

To try and tie things up - my understanding now is that vibrations from motor will eventually break the OF (typical wear and tear), but issues with TC (which in this case I provoked with wrong tire replacement) may accelerate the process substantially.

@AndrewC1989 I also figured that xDelete (switching from AWD to RWD), if I had it, would remove the stutter and relieve TC. Checked your build btw, saw you are currently on the same setup I tried with new winter tires, but you're on AllSeasons instead. I can only assume TC is also sensitive to AS XL tires in that setup as it is on M+S XL and it only tolerates summer tires in that size (probably due to weight and thus the radial force variation)...


Lenghty post, I know, but hopefully it'll aid someone and prevent potential OF/TC failures. Or at least from choosing bad tire setup. :D