Transmission/Drivetrain issue this weekend, flatbed required

[brianeck]

I don't know exactly what the issue is yet as the car got to BMW yesterday. They are checking it out now and I'll update once we know more. . .

So what happened??

I turned left off of my street onto the main road nearby in 1st gear (car is 6mt) and went to get on it a little bit. I had probably applied about 2/3 throttle in sport+ which is plenty of go, and right around the 3k rpm mark I was mostly through the turn and fully applied the throttle, hoping for a little wheel spin. I had a first time passenger and wanted to have a little fun. I hit a little bump in the road and all of a sudden the RPMs flared up and skyrocketed towards redline and I immediately depressed the clutch because I could tell something slipped. I shifted into 2nd and the RPMs were sort of "free floating" and there wasn't any power transfer occuring, plus I heard a pretty awful grinding sound coming from what sounded like the rear of the car.

I pulled over to the side of the road, and a "Rear Differential Error" came up on the dash. I wasn't really in a safe place to leave the car, so I immediately tried to move into the hospital parking lot that was just in front of me. I tried 1st, 2nd, and reverse and while I could engage the gear, there would be absolutely 0 power transfer from the engine to the rear wheels. Add to that a horrible clunking sound as well, which made for a very quick trial because whatever the sound was clearly wasn't good and I didn't want to do any further damage.

I restarted the car to see if it would tell me any more about the error, and actually there was not an official error being thrown upon restart.

I called BMW Road Side and they came to pick up the car in about 60 minutes. Since I was 3 blocks from home I just pushed the car into a slightly better spot and walked back home until the truck arrived.

Very, very weird issue. Some additional background: 13,000 miles or so on the car, it's my 3rd manual vehicle, and I haven't been overly abusive to the clutch or anything. . .

**Oh 1 more thing: For the last 3 weeks or so I've had a strange issue with 1st gear not fully engaging. . . I could shift up to the gate but it would stick a little. If I shifted into 2nd and then up to first it would work every time, so I was thinking there was probably a synchro issue of some kind but that it wasn't serious. Maybe I was wrong and it was much more serious after all!

Update: I blew the right rear axle entirely. It was indeed the bump I went over as I finished the turn. Friggin potholes. Axle on backorder, I was advised it may be Xmas before I get Geri back. Crap.

[jwzimm]

Sounds like the diff let go. I wonder if a rear tire came off the ground. I know gear-type LSD's do not like that very much but I think ours is clutch-type.

Keep us posted on what BMW has to say.

[04RC51]

Glad I didn't get the 6mt!

I'm sure they will fix it up and you will be back on the road in a month or three. Hang in there OP!

[afadeev]

Originally Posted by jwzimm

Sounds like the diff let go. I wonder if a rear tire came off the ground.

+1 on diff meltdown.
Should be fully covered by warranty, as there no obvious ways anyone can abuse a diff, short of running it w/o fluid.

Originally Posted by 04RC51

Glad I didn't get the 6mt!

Most likely transmission choices has had zero influence on this outcome.

a

[04RC51]

Originally Posted by afadeev

Most likely transmission choices has had zero influence on this outcome.

a

Whoooosh!

[DaBean]

+1 on the diff issue. The sounds you're describing sound like diff issues warning signs, and then this bump probably sealed the deal. Could be loose parts in the diff, hell even a loose mounting of the diff or subframe causing it to break apart under stress and load

[MFNATIK]

blame it on the fire truck incident jk

[vstM3]

There was another thread somewhere not quite similar but same as in the first gear to redline and then all kinds of things happened. In the end BMW refused any warranty done due to this. They are able to see the log of when you shift and the rpms. Good luck

[dmk08]

Originally Posted by vstM3

There was another thread somewhere not quite similar but same as in the first gear to redline and then all kinds of things happened. In the end BMW refused any warranty done due to this. They are able to see the log of when you shift and the rpms. Good luck

And thats why you don't buy M cars from crappy dealers

[DaBean]

#SMG #MDCT ftw

[brianeck]

Originally Posted by vstM3

There was another thread somewhere not quite similar but same as in the first gear to redline and then all kinds of things happened. In the end BMW refused any warranty done due to this. They are able to see the log of when you shift and the rpms. Good luck

The RPMs only went up near redline when whatever disconnected actually disconnected, I'm not worried about them seeing the shift points or anything.

I still slammed my left foot down on the clutch as soon as I noticed the RPMs going skyward as any practiced manual driver would, and I think I managed to do this before they actually did go beyond the redline. . . But either way even if they did the only reason they went so high was a direct result of a mechanical failure of some kind and whatever slipped caused them to jump way higher since there was no longer any resistance from the road/rear wheels/rear diff.

I think you guys are probably right that it was a diff issue (and that is the code the car threw as well) since the audible sounds were coming from the rear of the car.

In any event, this will most certainly be a warrantied claim and I'm not worried about it in the slightest.

[dmk08]

Originally Posted by brianeck

The RPMs only went up near redline when whatever disconnected actually disconnected, I'm not worried about them seeing the shift points or anything.

I still slammed my left foot down on the clutch as soon as I noticed the RPMs going skyward as any practiced manual driver would, and I think I managed to do this before they actually did go beyond the redline. . . But either way even if they did the only reason they went so high was a direct result of a mechanical failure of some kind and whatever slipped caused them to jump way higher since there was no longer any resistance from the road/rear wheels/rear diff.

I think you guys are probably right that it was a diff issue (and that is the code the car threw as well) since the audible sounds were coming from the rear of the car.

In any event, this will most certainly be a warrantied claim and I'm not worried about it in the slightest.

Couldn't have happened to a prettier car... one of the only F80s that makes me jealous. Hope she is back on the road soon sir.

[brianeck]

Update: I blew the right rear axle entirely. This means it was indeed the bump I went over at near WOT haha.

Rear axles are backordered and aren't even in stock in Germany. My adviser just told me its going to be 3-4 weeks minimum for the part to arrive, and that they can't tell if the differential itself is damaged until they get in there.

Thankfully my dad has left me with his very capable 5.2L Cherokee as he just moved to Grand Cayman so I don't need a loner car.

And about the firetruck incident. . . I had literally JUST gotten my car back from Detailer's Domain after the re-installation of my Modesta and Xpel Ultimate on all the affected panels 6 days prior to this! I haven't had my poor car for the best part of the last 3 months and now I lose the last pre-sub zero driving months hah. Oh well.

Unbelievable.

[DaBean]

Now that I remember, I wonder if when the firetruck hit your car it damaged/dislodged the diff and rear end. Seems strange that this only started happening after your hit.

Did you file an insurance claim / police report after the hit? This might come in handy...

[brianeck]

Originally Posted by DaBean

Now that I remember, I wonder if when the firetruck hit your car it damaged/dislodged the diff and rear end. Seems strange that this only started happening after your hit.

Did you file an insurance claim / police report after the hit? This might come in handy...

I did I have a police report and an insurance claim filed. It is unlikely to be related, as the firetruck hit the left rear and the right rear is what just broke. The firetruck really only did cosmetic damage, but either way the reports are all there if it does become an issue.

[brianeck]

Originally Posted by DaBean

#SMG #MDCT ftw

Hah now that we know it was the rear axle it wouldn't have made a difference if I was in the manual or the auto The only difference is I would have been having less fun driving when it happened in the DCT

[myzmak]

Lucy sends her warmest regards to her boat-mate Geri Haliwell and wishes GH a speedy recovery!

(sorry to hear this happened man....!)

[dkhm3]

Originally Posted by brianeck

Update: I blew the right rear axle entirely. This means it was indeed the bump I went over at near WOT haha.

Rear axles are backordered and aren't even in stock in Germany. My adviser just told me its going to be 3-4 weeks minimum for the part to arrive, and that they can't tell if the differential itself is damaged until they get in there.

Thankfully my dad has left me with his very capable 5.2L Cherokee as he just moved to Grand Cayman so I don't need a loner car.

And about the firetruck incident. . . I had literally JUST gotten my car back from Detailer's Domain after the re-installation of my Modesta and Xpel Ultimate on all the affected panels 6 days prior to this! I haven't had my poor car for the best part of the last 3 months and now I lose the last pre-sub zero driving months hah. Oh well.

Unbelievable.

wow, is that covered under warranty or insurance? damn bad luck.... sorry to hear.

[dmk08]

Originally Posted by dkhm3

wow, is that covered under warranty or insurance? damn bad luck.... sorry to hear.

Why wouldn't it be covered?

[dkhm3]

Originally Posted by dmk08

Why wouldn't it be covered?

is it due to an "accident" from the bump or is it considered a failure of the part? if it is an accident, then go through insurance.

if it is a part failure then go through warranty.

[GrussGott]

Hopefully you will keep us posted on the error messages and diagnosis... Seems like there's been a few of these weird things going on with the 6MT, granted they seem unrelated and this definitely sounds like a blown diff.

[brianeck]

Originally Posted by dkhm3

is it due to an "accident" from the bump or is it considered a failure of the part? if it is an accident, then go through insurance.

if it is a part failure then go through warranty.

They are calling it a part failure. The bump I hit was legit barely even noticeable, I've hit WAY worse potholes around town, I guess I hit this one just right (slightly sideways haha).