Looking for R171 to R172 experience and essential spec / features / upgrades

comparison threads

Thanks sarge, you might as well delete this thread now... because noone is chiming in to answer the experience ownership and acquisition questions about SLK vs SLC, and how they drive when benched against an r17, now that you've pointed me to a Google full of threads comparing the the looks of r171 vs r172

@RobbieG @LeonardoDaBenz

unless there is a violation of forum rules (none here), we don't remove so early, if at all. Someone may jump in later.

@Jay_Bruce this post will help you spot the various options on the SLK.


I don’t think my view of the available options has changed since I first posted. The only real exception is the dual‑zone climate control. I’ve found it genuinely excellent, cool air on my feet during the summer while keeping a takeaway hot in the passenger footwell with that side set to maximum temperature.

I’m not fully up to speed on all the differences between the SLK and the SLC. The SLC does have an updated infotainment system, which I believe includes Android Auto and Apple CarPlay. However, if the SLK is fitted with the Audio 20 unit and the sat‑nav cradle in the glovebox, you can replace the Mercedes navigation module with an aftermarket unit that adds this functionality.

Also don't forget you can ask for a datacard to se all the fitted options.

Few thoughts, from someone who upgraded from a MY2010 R171/350 to a MY 2018 SLC43.

The Unicorn to get in my opinion would be a 2013/2014 very well spec'd R172/350.
(But with car leasing, it was cheaper to get a R172/55 - Yes, lovely bit of kit and no harm in owning a V8 while you can ..!!)

The R172/SLC is just a face lift R172/SLK.
So has different lights and bumpers, and some updated Tech inside. Then Android Auto & Apple Car Play option was added ~2017..

Options can make a big difference for Me, but that is a long discussion. But one thing you do need for a Scottish Winter is the upgraded headlights..?
(The Standard H7 filament bulb offering, is "poor" on a wet winters night....)

As for fuel type, if you do lots of commuting miles, a diesel would make sense - Though need to make sure it's ULEZ compliant, as likely to be rolled out to more & more Towns ..?

As for 9G against 7G. Yes the 9G does quicker gear changes and maybe more mpg? But it also costs more to service, as the plastic gearbox pan is replaced as part of the gearbox service (£££) Not just the filters & oil...

The down side to upgrading to a R172 is the turbulence in the cabin due to the Wind Deflector change. I've spent a lot of time & effort in trying to improve this....

Welcome to ask questions about the above

Hi I have an SLK 250d 2015 with the 9g box.
as you say it was only on 2016 model year, mine was one of the early ones registered late October 2015.
I had an equivalent SLC as a courtesy car a few times. Mechanically they are the same engine and box and the nine speed suits the diesel well. It’s a bit faster and amazing economy. Generally mid 50’s mpg with an easy 60 plus on a run. Adblue is a once per year fill and no issues.
Mine has now done over 100k miles And I have had it from new.
Gearbox service is five years or 76500 miles, cost me £350 at a specialist who updated the online history.
I have had a failed NOx sensor, it’s quite common and replacements can be difficult as MB did a diesel gate software update. Mine has not been done, as it runs the egr more and uses more adblue. I discovered the NOx sensor is actually and NGK NS11A and I obtained a repair kit and spliced it in keeping the original software, that was over two years ago. Cost £100.
As for SLK or SLC I prefer the SLK style. It’s a personal choice but I do not think the newer plastic bumpers fit well with the original metalwork. The bit I really did not like was the C Class steering wheel as it is configured for a different information system and the buttons are in the wrong places. You may love it, it’s personal.
I think the SLC infotainment is better, but I have audio 20 so put in a car play box and reversing camera.
Spec wise AMG line gets leather, body kit and lowered suspension with 18 inch wheels. But it still looks what I think are some basics. Eg lumbar support only comes with electric seats. Pan roof was an extra despite being fitted, they cover it with foil if you do not pay. A few other bits are lacking as well so check the spec you want. I specced mine up but it cost a few thousand.
Eleven years into ownership it has been great. Still looks fab, drives fab, and turns heads. I think the interior is a real step up from the R171.
Oh and yes the standard halogens are rubbish, they have long life bulbs (candles). I popped in some 150% bulbs and it’s a lot better.

Little more to add to the owner feedbacks above. I went from a R171 55 to a R172 350. As @Trev5 noted, the 2013/2014 350 is pretty darn good MY to look into. Can't comment on the diesel version cos that is not common here in America. Mine now has 141K+ miles and still going strong. Body is pristine - no dents, rust or whatever anywhere... paint still in great condition (could use a good rub-down tho')... The interior wind noise is significantly reduced using the deflector made by @Trev5 (5+ years on, and works like a charm... me vouch for it ) Mine is also fairly loaded with the doodads like Magic Sky, dash clock, factory Nav, AMG body kit, etc... plus a few cosmetic "upgrades" I added which makes the driving experience even better... bigger flappers, exhaust, larger wheels (19"), throttle booster, etc...

Things to worry about fixing in the R172 - cats (mine needed replacement at ~30K miles), air bag SRS error (also in my R171), delaminated roof, delaminated glove box, frequent tire replacements and a leaky radiator (on-again/off-again). Main battery in mine lasted 100K miles before needing replacement.

All good stuff about R172 350s... look for one and drive it to decide. It is the mid-trim (sweet spot) of all SLK/SLCs. I am keeping mine till it dies or I die... whichever comes first...

Good luck, and let us know what you ultimately decide.

Unsure if the US Specs were the same for MY 2016 as you would have, but here was what I remember my priorities being.
Primary use is a commute of round trip 80 miles, so fuel efficiency and maintenance was a factor for choosing powertrain as well as maintenance schedule.
When I buy things over a certain price, I think of them as using for many years, ideally a couple decades.

Previous vehicles I have had, and friends have had, I did not want the driver assist and various related sensors associated. Also did not want the airbag type of suspension.
I did, however, want air scarf, keyless, remote roof operation, better sound system (These all came with option 1), I also wanted the Bi-Xenon headlamps, blind spot assist, Command Navigation, larger display, Dual zone climate control. BI was looking for.
Magic Sky was a nice to have, but not as important as option 2.
Interior colors are a personal choice for sure.
I had read about leather vs MB Tex, and wanted leather. Specifically light, either Beige or grey. Trim, I preferred black.
The 9G-tronic was a feature I wanted after reading quite a bit about it.
Wanted the more angular front and side appearance, along with small spoiler. Took me to the Sport appearance package, gave me the 18" wheels I liked, the body styling and the cool red interior lighting.
All these pointed me towards a single year to look for, the 2016.
As others had pointed out, there were some changes between the SLC and SLK. Another lesser known difference is the fuel tank size. Mine is 18.5. in 2017, they shrunk it to 15.9 something. That is a full commute to work and back of fuel.

Anyway, those are the options, and generally my thought process on why I chose what I did. I never drove a previous model, they just did appeal to me from a style perspective. Everyone has different preferences and priorities.

9 years of ownership later, I bought it with 9K miles, currently at 96K miles. I still smile every time I drive it. Happy with all the decisions to have the one I got.
Total out of pocket expense for unplanned/non routine maintenance or wear items is sitting at $25. I had to replace the oil dipstick earlier this year.
The only things I would change would be to add Carplay, which I did via K-Tech. Also added a reversing camera. Also a couple minor appearance changes that only someone who knows they were changed would even notice.

Best of luck in your search. Took me about 6 months to find the right color and options