The more you know: SLS Replacement Transmissions are built on an "as needed" basis.

"Battery Tender Unnecessary" (carac)
11/19/2015 at 09:30 • Filed to: None

So after 3 and a half weeks of diagnostics, replacing/rewiring control units, etc. they finally agreed with what I told them on day 1, the SLS needs a new transmission. I knew this day one because at least 5 SLS owners that frequent SLS message boards (something probably less than 1% of the 2400 SLS owners in the US do) had the exact same sequence of events/symptoms as my car and every one needed a new transmission. The transmission used in the SLS, 458, 488, F12, etc. is not dealer serviceable. If something goes wrong, you just replace it.

But now I have a better idea why they jump through so many hoops prior to getting a replacement: Mercedes has to commission the production of a single gear box, fabricate and assembled from scratch from the supplier, which takes somewhere around 8 weeks. Then the transmission has to be shipped from Europe to my dealership, a trip of about 2 weeks. Then it takes about a day and a half to replace the trans-axle transmission in the SLS.

So. With any luck, I will have the SLS back sometime in early February. I’ve been told the reason for this is that Mercedes doesn’t want to be sitting on a pile of transmissions that might have a design flaw they only notice down the line. Failed transmissions are sent back to be torn down and examined, which has yielded a few design updates over the years, so hopefully the 2015 built SLS transmission will be less prone to failure than the early-2012 one it came with. So far, this is the only major issue that has been reported by multiple owners. The car is otherwise bulletproof. Here’s hoping they’ve “fixed” whatever causes these clutch pack failures, because commissioning a $20-25k transmission every 30k miles isn’t something I’m looking forward to.

DISCUSSION (39)

Cé hé sin > Battery Tender Unnecessary
11/19/2015 at 09:35

Getrag (I think it’s them) have been making this unit for several years so it’s surprising they haven’t got it right yet. Do you know if McLaren, Ferrari etc have the same issue?

BeaterGT > Battery Tender Unnecessary
11/19/2015 at 09:39

This does not bode well for my future used-supercar purchase. Best of luck getting this sorted out. Just read your other article, glad it’s covered under warranty.

Milky > Battery Tender Unnecessary
11/19/2015 at 09:45

Kinja'd!!!

Wait a tick, do you get a C-class as a loaner when you bring in a SLS?!

Rico > Cé hé sin
11/19/2015 at 09:47

Maybe Ferraris/McLarens from that MY.

CCC (formerly CyclistCarCoexist) > Battery Tender Unnecessary
11/19/2015 at 09:48

Is the transmission also built by AMG or is it just subcontracted to another company?

Brian Silvestro > Battery Tender Unnecessary
11/19/2015 at 09:58

once upon a time I knew of a rental SLS that went through 4 transmissions by the time it hit 60k miles

Rico > Brian Silvestro
11/19/2015 at 10:06

I know this story too. I’m sure at no point in time except in Manhattan bumper to bumper traffic was that thing driven gingerly.

MLGCarGuy > Battery Tender Unnecessary
11/19/2015 at 10:09

I suspect that the same gearbox doesn’t have this issue in the 650S, 458, F12, etc. because owners of those cars keep them as garage queens, while SLS owners tend to enjoy driving their cars more.

Cé hé sin > CCC (formerly CyclistCarCoexist)
11/19/2015 at 10:20

It’s by Getrag who also supply Ferrari and McLaren.

Leadbull > CCC (formerly CyclistCarCoexist)
11/19/2015 at 10:21

I believe Getrag is the number one dual clutch transmission kingpin.

JR1 > Battery Tender Unnecessary
11/19/2015 at 10:41

Are they giving you a C-class for a loaner? How annoying you deserve at least a C63 AMG

Rico > JR1
11/19/2015 at 11:01

How are people jumping to this conclusion?

random001 > Battery Tender Unnecessary
11/19/2015 at 11:08

SLS? SLS?!?! SLS!!!!!!!!!!!!!!!!!!

Opposite Locksmith > Battery Tender Unnecessary
11/19/2015 at 11:10

Same thing happened to my f12, except I don't have an f12

Jonathan Harper > Battery Tender Unnecessary
11/19/2015 at 11:12

I know the CCC SLS had more than 2 replacements in it’s life in the fleet. I think it may have been a few more than that, too.

JR1 > Rico
11/19/2015 at 11:16

The C-class is right there in the photo

Rico > JR1
11/19/2015 at 11:23

Perhaps I just think it’s a stretch since even E class people get E Class loaners and not C class loaners. He also DDs a FiST/ RR SVR I doubt he’d want a loaner. When I took my car in for service it was parked next to a red AMG GT but unfortunately that was not my loaner!

Though it should have been because maybe it’d convince me to get an AMG GT but since it wasn’t I won’t even consider getting one now!/s

B_dol > Battery Tender Unnecessary
11/19/2015 at 13:27

So what you’re telling me is the stable is low on its Mercedes quota short-term... time for a 2nd year AMG GT lease (issues somewhat worked out)?

AMGtech - now with more recalls! > B_dol
11/19/2015 at 14:06

GT trans is based on that unit but has quit a few updates both to software and hardware, that are unfortunately not backwards compatible with SLS as far as I know. Hopefully this means the GT won’t have the same issues, but time will tell

B_dol > AMGtech - now with more recalls!
11/19/2015 at 14:39

Good to know. I also recall some first year teething issues software, electronics, etc. on the GT that were scaring away some buyers.

davesaddiction @ opposite-lock.com > Battery Tender Unnecessary
11/23/2015 at 15:14

Geez.

CAcoalminer > Battery Tender Unnecessary
12/04/2015 at 01:56

The transmission used in the SLS, 458, 488, F12, MP4-12C, 650S, etc.

You are slightly incorrect. The F12, 488, and SLS all use the same Getrag transmission (7DCL750) while the McLarens (650S, 12C, etc.) utilize a Vocis, which is a subsidiary of Graziano.

Battery Tender Unnecessary > CAcoalminer
12/04/2015 at 02:17

Yeah, I fact checked that after posting. Need to update it.

His Stigness > Battery Tender Unnecessary
04/12/2016 at 00:00

I’m surprised Mercedes doesn’t use re-man units, since they are obviously having to replace units, unless they literally made no spares and are rebuilding the transmission you send in. Who knows though.

His Stigness > AMGtech - now with more recalls!
04/13/2016 at 16:54

Hey so is there some secret that makes it impossible to bleed the cooling system on a V12? We have an 05 Sl600 which needs an alternator, and I guess our Mercedes neighbor doesn’t touch them because he can’t bleed the cooling system.

AMGtech - now with more recalls! > His Stigness
04/13/2016 at 21:32

Yeah. You need the octopus. The main (high temp) cooling system is perfectly normal. It’s the low temp system that is more complicated. The octopus draws vacuum from the water neck at the center rear of the engine, and also from the two bleed valves on the charge air coolers. Then once there is vacuum, you open it to draw coolant in and open the bleed valves as well to let coolant, and air, out. It takes a few gallons to do properly. It basically acts like a flush, but it isn’t, a gallon or two of new coolant will come out of the bleeders by the time you’re done. And if not don’t properly misfires and potentially turbo damage can result. The octopus uses a vacuum/coolant reservoir and another just coolant reservoir. I don’t suggest attempting it without these.

His Stigness > AMGtech - now with more recalls!
04/13/2016 at 22:32

Holy balls!

About an hour after I asked you I asked what the big deal was, and they told me it required a stupid expensive tool to do it, so that was ah ha moment.

Let’s say, hypothetically, I wanted a Mercedes V12 and wanted to do all the work on it, how much would such a device possibly cost me?

Edit: Would this process work?

AMGtech - now with more recalls! > His Stigness
04/14/2016 at 01:02

You don’t. Seriously. I mean you really don’t want a V12. Unless you budget another $10k in cash/credit cards for repairs.

That setup looks pretty janky, but I imagine it would work at least sometimes. But if your intercooler pump doesn’t kick on it certainly won’t work. And it looks messy. The other thing is, looks like he clamped his hoses, so most of his coolant stayed in the system. Mostly empty, I doubt it would work, but honestly I don’t really know. The system is very susceptible to heat, so places that regularly exceed ~90 (socal, etc.) are going to be far more likely to have issues from improper bleeding than perhaps someone in Canada.

His Stigness > AMGtech - now with more recalls!
04/14/2016 at 01:06

What if I were to do all the work myself, including taking the engine out to do the oil cooler gasket thing which apparently leaks liters a minute.

Can you not power the intercooler pump through the scan tool so that you can pump out the air pockets?

AMGtech - now with more recalls! > His Stigness
04/14/2016 at 01:30

Dropping the engine is a ton of work. But the issue with owning one isn’t labor. It’s parts. It’s always been parts. Fluids alone for dropping the engine will run you a couple hundred (10 liters Mobil 1, 3-4 gallons coolant/water, ATF, 10 liters ABC fluid). But that oil cooler is probably between 40-50 hours IIRC, and yes it spews like Austin Powers just woke up from cryo sleep.

Yes, with a compatible scan tool, assuming your pump works at all. Assuming your pump flows properly. Assuming you didn’t reconnect some coolant hoses backwards when you reinstalled the engine. Assuming the pump is at all strong enough to get every little pocket out of all the coolers, radiators, and tiny little lines without the aid of vacuum.

V12 cars are why the term “bleeding edge” exists. If you really want a V12 look up how much spark plugs and insulator boots cost. And coils. And some ABC components. And brakes. Etc.

His Stigness > AMGtech - now with more recalls!
04/14/2016 at 01:38

Oh I know the issue is with parts, I’ve had a taste of that with my W202 and Golf.

However, I really, really want a V12, but I wouldn’t want one till I have three other cars, at least, and a full lift. Then I wouldn’t have to worry about time or space. Nor would I have to worry about money at that point if I can afford four German cars and a lift.

I know it sounds like a pipe dream, but it’s something I’m continually working towards. My first step was becoming a technician. Second step getting lots of tools. Third step is getting my BA. My next step is law school, which will hopefully begin next year.

AMGtech - now with more recalls! > His Stigness
04/14/2016 at 01:52

Not to be a dick, but no, you haven’t. Quadruple what your parts have cost on your previous German cars. And then quadruple the number of repairs the car will need.

I feel like I have to be blunt to the point of rude when trying to illustrate how extensive V12 and ABC cars are to own. People think I’m exaggerating. I’m not. It’s scary how cheap these things are because people think they can tavarish them and be fine. You can’t. These cars will screw you. Unequivocally. Unless you are prepared. Buy the absolute nicest one you can find in the country, do not spare any expense on shipping, or plane tickets, or the pre purchase inspection. Get a warranty if possible. Budget a bare minimum of $5k for repairs immediately.

I hope you achieve your goal someday. Just keep working as hard/smart as you can.

Did you get to drive a V12 finally?

His Stigness > AMGtech - now with more recalls!
04/14/2016 at 02:00

I take no offense, because I’m sure it sounds like I’m ignoring you. I’ve looked up parts prices on the V12, but just a little. Like I said though, I wouldn’t buy one till I was super secure because I know, or think I know, how expensive they can be.

Nope! There have only been three V12's to pass through my shop, and I haven't worked on them, so I don't get to drive them =( Oh well. One day I'll go test drive one.

AMGtech - now with more recalls! > His Stigness
04/14/2016 at 02:04

Avoid driving one as long as you can. You may lose your resolve to wait until you’re financially secure enough to buy one and just pull the trigger instead.

His Stigness > AMGtech - now with more recalls!
04/14/2016 at 02:14

I can assure you that won’t happen. I borrowed an E46 M3 for a whole week, and that was after I fell in love with it, and still managed to resist buying it till I find the right one, for the right price, and had back up funds.

Are Mercedes V12's really that good though that they can make smart people do such stupid things?

AMGtech - now with more recalls! > His Stigness
04/14/2016 at 02:32

“Daddy, it’s just prom, I’m not going to get pregnant” said every mtv teen mom ever.

Yes. Drive one. It’s hard to explain. :)

Kyle > Battery Tender Unnecessary
08/23/2017 at 04:49

I am going through the same issue with my 2012 SLS. They first replaced the control unit for me and told me problem was fixed. 4 months later I get the same problem again (error: reversing position not possible) and gear stops shifting all of a sudden. Now they are telling me I need to replace transmission. Should I replace or sell the damn thing?!

Rich > Battery Tender Unnecessary
04/17/2018 at 18:17

Hey there, I have a client that has a 2012 SLS that went into limp mode and the dealership failed to identify the problem which eventually led to a transmission replacement. Would you please contact me? I have a couple of questions regarding the down time and who you were in contact with at the dealership to resolve the issue. Rich@alaskalegalsupport.com

Thanks

gawdzillla > Battery Tender Unnecessary
11/29/2018 at 15:35

i’ve been dreaming of getting a SLS ...

maybe i should stick with the 911 / R8