Used M4 Concerns

[F32Sib]

Hello everyone,

Considering how inexpensive the earlier generation DCT M4/M3s have become, i'm sold on purchasing one. I've always done bolt ons/tunes to my cars (E92 N54, F32 N55) and enjoyed the life out of em! however, I've got a few concerns regarding the S55 after reading countless forum posts:

1. Is it safe to buy a used, out of warranty, stock or already tuned M4/M3? Will it hold up in reliability?

2. Does the GTS transmission flash reduce or worsen the probability of spinning the crank hub?

3. Considering the 2015/2016s are out of warranty, should I purchase an extended warranty even if I wish to tune it?

4. Should I stick to a 2015/12+ build because of the new bedplate implementation?

Best regards

[shortseller]

Not sure on the S55 but I do know the N54 was a crazy easy tunable motor with pretty good reliability other than the HPFP which got fixed. No crazy encryption programs to break or hub problems. Once tuned, crazy fast and now super cheaper than the S55 autos, especially after bmw went to the N55. Pick up a cheap 335is n54 and plug and play. Just food for thought.

[ShoNufff]

I bought a used 2015 M4 6MT stock with 40k miles on it last year. I've been running full bolt ons and tuned with no problems. Knock on wood. With the hub issue, everyone says it's a hit or miss. It could happen when you're stock or modded. So far this is one of the best cars I've owned. It's fun to drive, reliable and love the way it looks. Only thing I wish I could change is the exhaust sound haha.

[NickyC]

Buy the car, do not think twice. Do not buy an extended warranty if you intend to tune the car, that's pretty much money wasted. Save that extended warranty money you would have spent for eventual repairs.

These are amazing cars.

[1Down]

1. I would say it is safe, but you're buying a used car so always expect there to be an issue. This goes for any used car. Always be prepared for the unexpected repair.

2. I have never heard of the GTS transmission flash being a preventive measure for the crank hub. I wouldn't worry about it - the spun crank hub rate is so minute. Just be aware of it.

3. I wouldn't purchase an extended warranty. The value of the extended warranty is less than what you will end up paying for it - unless you have a MAJOR repair. If you're going to mod, expect the warranty to be void.

4. Bedplate update doesnt make a difference in regards to spun crank hub.

That being said, just get a pre-purchase inspection done. If all checks out, go for it. I have no regrets buying my M4, except for not getting a CS.

[stevenc]

My 2015 has been rock solid. No repairs to date.

Obviously with any used BMW its easy for something to go wrong and you end up with a $3k repair. As long as you are okay with that, then proceed ahead. Also find a good indy shop in the area so that if a major repair item does happen you can pay half of what the dealer will charge.

[Fast4d]

just buy a used one and consider the $3k crank hub fix part of the price.

you don't really need an extended warranty. if you tune/mod and it breaks you think they will cover it?

[cotmfk]

Get a pre-purchase inspection (PPI) for peace of mind. Roughly $600 for that, but it should tell you all of the issues with the car. It should include a leakdown/compression test which will give you information on the health of the motor.

Good luck, and happy hunting!