SLK 172 3rd generation
Discussion
I've found myself browsing these over the last couple of days and reading a few reviews. Never had a Merc and the thought does appeal.
From what I gather the main criticism is that they're not as sharp to drive as a Boxster, maybe not really sporty enough for a 2 seat roadster. The more I think about it, the less bothered I am by that. Can't be that bad surely? And a bit of comfort as a daily drive might be a good thing.
Which engine do people recommend?
On paper the 250 petrol looks okay to me. 204bhp is enough and decent torque should make it go fairly well. These seem to be reasonably good value to buy and running costs look fine. Any problems with the 1.8 4 pot in this generation?
A 350 V6 sounds nice but I can't work out if that's the one with the balance shaft issues, or did that just affect earlier cars?
The price jumps substantially for the V8 and is probably a bit out of my league. Not sure I need that kind of performance. Bet they sound good though.
It'd be good to hear from owners past and present cheers.
From what I gather the main criticism is that they're not as sharp to drive as a Boxster, maybe not really sporty enough for a 2 seat roadster. The more I think about it, the less bothered I am by that. Can't be that bad surely? And a bit of comfort as a daily drive might be a good thing.
Which engine do people recommend?
On paper the 250 petrol looks okay to me. 204bhp is enough and decent torque should make it go fairly well. These seem to be reasonably good value to buy and running costs look fine. Any problems with the 1.8 4 pot in this generation?
A 350 V6 sounds nice but I can't work out if that's the one with the balance shaft issues, or did that just affect earlier cars?
The price jumps substantially for the V8 and is probably a bit out of my league. Not sure I need that kind of performance. Bet they sound good though.
It'd be good to hear from owners past and present cheers.
The balance shaft issues were on the 350 from 2004 to 2008. The R171 facelift (A V low in the front bumper is a guide) from late 2008 is below 225g emissions, and over 300 bhp, I bought one. 
I did look at R172s with the blunt front and whilst they look a bit nicer inside, and are more economical, they are heavier so a tad slower. I couldn't see the reason why a 2012 R172 should retail at double what a 2010 R171 does, equivalent engine size and mileages.
I did look at R172s with the blunt front and whilst they look a bit nicer inside, and are more economical, they are heavier so a tad slower. I couldn't see the reason why a 2012 R172 should retail at double what a 2010 R171 does, equivalent engine size and mileages.
Ah right, so the 350 in the 172 is okay?
Is it NA or turbo?
I do prefer the looks of the 172 personally, inside and out. The SLK350's I've seen are around £14k or so which is only a grand or 2 more than the 250. One review dud say the 250 was a better buy, but that was talking about brand new when the price difference was a lot more.
There's a 250 for sale locally which I'd like to go and look at on Monday. No 350's nearby just yet but there's no rush.
Is it NA or turbo?
I do prefer the looks of the 172 personally, inside and out. The SLK350's I've seen are around £14k or so which is only a grand or 2 more than the 250. One review dud say the 250 was a better buy, but that was talking about brand new when the price difference was a lot more.
There's a 250 for sale locally which I'd like to go and look at on Monday. No 350's nearby just yet but there's no rush.
350's are good - I had one of the last 171's - no balance shaft issues - just a v6 normally aspirated 300+hp and a nice turn of speed when needed but very much more of a cruiser.
Bad points - the gearbox is a bit dim witted, economy not great 22-32mpg in mine (172 is supposed to be better), rear subframes rot - but get replaced FoC by dealers on cars long out of warranty, they are small inside, the photochromatic roofs can delaminate. Very spec dependant - imho you want the heated seats, park sensors and the air scarf.
They are nice cars but I swapped to a z4 g29 and the fact the design is 20 years newer is immediately obvious in terms ok performance, kit and noise and vibration. If your budget could run to a z4 20i 2019 thats where my money would go.....
Bad points - the gearbox is a bit dim witted, economy not great 22-32mpg in mine (172 is supposed to be better), rear subframes rot - but get replaced FoC by dealers on cars long out of warranty, they are small inside, the photochromatic roofs can delaminate. Very spec dependant - imho you want the heated seats, park sensors and the air scarf.
They are nice cars but I swapped to a z4 g29 and the fact the design is 20 years newer is immediately obvious in terms ok performance, kit and noise and vibration. If your budget could run to a z4 20i 2019 thats where my money would go.....
Budget doesn't stretch to the new Z4. They seem to start at £26k. Besides which it's the folding hard top I'm more interested in.
I do like the E89 Z4 but I've had a BMW before and like the thought of a Merc. Wouldn't rule it out though.
I'll see if I can get a look at the local one tomorrow. Not seriously considering buying right now and that one doesn't have the air scarf which I'd guess could be a problem come resale time. Besides which, if the 350 has no inherent problems then that would seem to be the pick.
I do like the E89 Z4 but I've had a BMW before and like the thought of a Merc. Wouldn't rule it out though.
I'll see if I can get a look at the local one tomorrow. Not seriously considering buying right now and that one doesn't have the air scarf which I'd guess could be a problem come resale time. Besides which, if the 350 has no inherent problems then that would seem to be the pick.
Not sure where you are in the UK but this 350 is very nice, I looked at it for a client but ultimately they went for an SLK55 as they were similar money (171) & more theatre:
https://www.autotrader.co.uk/car-details/202203263...
Although this one with the contrast interior looks a peach at 14k:
https://www.autotrader.co.uk/car-details/202305307...
https://www.autotrader.co.uk/car-details/202209069...
The 172 is a good car that can be hustled along at a lick but it's not as sharp as some others but it's a better daily, balance shaft issues were pretty much sorted from 2008 onwards.
The 350 is better suited to the car the 250 is okay but the 6 pots the pick, although it's very hard not to recommend the R171 SLK55 at this price point:
https://www.autotrader.co.uk/car-details/202306078...
https://www.autotrader.co.uk/car-details/202203263...
Although this one with the contrast interior looks a peach at 14k:
https://www.autotrader.co.uk/car-details/202305307...
https://www.autotrader.co.uk/car-details/202209069...
The 172 is a good car that can be hustled along at a lick but it's not as sharp as some others but it's a better daily, balance shaft issues were pretty much sorted from 2008 onwards.
The 350 is better suited to the car the 250 is okay but the 6 pots the pick, although it's very hard not to recommend the R171 SLK55 at this price point:
https://www.autotrader.co.uk/car-details/202306078...
I have an R172 SLK55 AMG. It's a 2012 model, which I bought second hand and have owned for over 7 years. It's been a lovely car to own and drive.
Yes I enjoy the theatre of the V8 in such a small car. It's the top of the range so comes with all the lovely trimmings. It does feel luxurious with the nappa leather, air scarf etc.
I had the silencer removed to add more drama to the sound which I find too quiet given there are two sets of cats.
It's been very reliable but I keep it garaged so it doesn't get weathered. The first year when I bought it, I had a couple of common issues which needed fixing:
- wheel speed sensors are notoriously bad on Mercedes, they failed, lit up the dash like a Christmas tree. It stops cruise control, ABS, traction control, brake hold. Other than that you can still drive as normal.
- switch valve in the exhaust which shuts off two exhausts for "C" mode (Controlled Efficiency) when it runs on four cylinders (cylinder deactivation). The motors needed replacing. The failure leads to the valve bouncing on and off sporadically but otherwise drives normally in Sport mode. Not sure if this is only on the V8 model.
So neither of those two issues stopped the car from being driven and (touch wood) it's been fine for the last 6 years other than tyres and servicing.
Make sure gear box oil has been changed at some point. Mine was due at 37,500 miles and 5 years. If you buy a car over 7 years or 50,000 miles then I would want to make sure that this has been done or at least have it done when you buy it.
Go through the various drive modes and try the kick-down. If these all work fine then it is ok and just get the oil replacement after you purchased but would be price haggle point if not done.
Driving wise, it handles well and is refined enough. The harder suspension is felt on small bumps. Yes it is not sharp on turn-in compared to a Boxster/Cayman.
With the roof up, it is refined like a saloon Mercedes but has better handling due to being lower down and smaller nimble car. With roof down, it's lovely as an open top sports car.
Yes I enjoy the theatre of the V8 in such a small car. It's the top of the range so comes with all the lovely trimmings. It does feel luxurious with the nappa leather, air scarf etc.
I had the silencer removed to add more drama to the sound which I find too quiet given there are two sets of cats.
It's been very reliable but I keep it garaged so it doesn't get weathered. The first year when I bought it, I had a couple of common issues which needed fixing:
- wheel speed sensors are notoriously bad on Mercedes, they failed, lit up the dash like a Christmas tree. It stops cruise control, ABS, traction control, brake hold. Other than that you can still drive as normal.
- switch valve in the exhaust which shuts off two exhausts for "C" mode (Controlled Efficiency) when it runs on four cylinders (cylinder deactivation). The motors needed replacing. The failure leads to the valve bouncing on and off sporadically but otherwise drives normally in Sport mode. Not sure if this is only on the V8 model.
So neither of those two issues stopped the car from being driven and (touch wood) it's been fine for the last 6 years other than tyres and servicing.
Make sure gear box oil has been changed at some point. Mine was due at 37,500 miles and 5 years. If you buy a car over 7 years or 50,000 miles then I would want to make sure that this has been done or at least have it done when you buy it.
Go through the various drive modes and try the kick-down. If these all work fine then it is ok and just get the oil replacement after you purchased but would be price haggle point if not done.
Driving wise, it handles well and is refined enough. The harder suspension is felt on small bumps. Yes it is not sharp on turn-in compared to a Boxster/Cayman.
With the roof up, it is refined like a saloon Mercedes but has better handling due to being lower down and smaller nimble car. With roof down, it's lovely as an open top sports car.
Great info thanks guys.
ZX, I had seen the silver 350 at 911box but it is 155 miles away. Although I do like the thought of the V8 55 it's a bit difficult to justify for me. I'd want the 172 as I much prefer the way they look inside and out and its a more modern car. The 2009 V8 is £695 tax and combined 23mpg whereas the later 350 V6 is £290 tax and 39mpg which is quite a difference. And 300bhp is more than enough for my needs. I do find it incredible that the later V8 manages to squeeze into the lower tax bracket. It must be the only V8 to do that? But they start at £22k which is a big premium over the V6.
ZX, I had seen the silver 350 at 911box but it is 155 miles away. Although I do like the thought of the V8 55 it's a bit difficult to justify for me. I'd want the 172 as I much prefer the way they look inside and out and its a more modern car. The 2009 V8 is £695 tax and combined 23mpg whereas the later 350 V6 is £290 tax and 39mpg which is quite a difference. And 300bhp is more than enough for my needs. I do find it incredible that the later V8 manages to squeeze into the lower tax bracket. It must be the only V8 to do that? But they start at £22k which is a big premium over the V6.
If I were buying today then I'd be most interested in this one.
http://www.autotrader.co.uk/car-details/2023022746...
However, this one really does it for me.
http://www.autotrader.co.uk/car-details/2022112419...
There is always that 'you only live once' feeling!
I still plan to look at the 250 tomorrow as its only 10 miles away. It'll give me the chance to see if the SLK is a car I could really live with.
http://www.autotrader.co.uk/car-details/2023022746...
However, this one really does it for me.
http://www.autotrader.co.uk/car-details/2022112419...
There is always that 'you only live once' feeling!
I still plan to look at the 250 tomorrow as its only 10 miles away. It'll give me the chance to see if the SLK is a car I could really live with.
ChrisH72 said:
Great info thanks guys.
ZX, I had seen the silver 350 at 911box but it is 155 miles away. Although I do like the thought of the V8 55 it's a bit difficult to justify for me. I'd want the 172 as I much prefer the way they look inside and out and its a more modern car. The 2009 V8 is £695 tax and combined 23mpg whereas the later 350 V6 is £290 tax and 39mpg which is quite a difference. And 300bhp is more than enough for my needs. I do find it incredible that the later V8 manages to squeeze into the lower tax bracket. It must be the only V8 to do that? But they start at £22k which is a big premium over the V6.
The low tax is due to cylinder deactivation on the 172 55's.ZX, I had seen the silver 350 at 911box but it is 155 miles away. Although I do like the thought of the V8 55 it's a bit difficult to justify for me. I'd want the 172 as I much prefer the way they look inside and out and its a more modern car. The 2009 V8 is £695 tax and combined 23mpg whereas the later 350 V6 is £290 tax and 39mpg which is quite a difference. And 300bhp is more than enough for my needs. I do find it incredible that the later V8 manages to squeeze into the lower tax bracket. It must be the only V8 to do that? But they start at £22k which is a big premium over the V6.
I hope it might help, but I would say the R172 350 has a heavy engine upfront and doesn't really suit the chassis. It doesn't have the rigidity the v8 has, and in my experience understeers heavily and doesn't feel well resolved.
I bought the Mrs a 250 CDI. HEAR ME OUT!! It rides on a wave of torque, is an effortless cruiser, and handles well enough to have fun. Depending on what you're coming from, they reach their handling limits pretty quickly though. I got a Celtic remap taking it to 255 bhp and a 410 ft/lb of torque in a small car.
To top it off, we get 600 miles to a tank. I wouldn't rule it out...as much as I wanted to hate it, I've grown to love the bloody thing. Damn.
I bought the Mrs a 250 CDI. HEAR ME OUT!! It rides on a wave of torque, is an effortless cruiser, and handles well enough to have fun. Depending on what you're coming from, they reach their handling limits pretty quickly though. I got a Celtic remap taking it to 255 bhp and a 410 ft/lb of torque in a small car.
To top it off, we get 600 miles to a tank. I wouldn't rule it out...as much as I wanted to hate it, I've grown to love the bloody thing. Damn.
Hmmmmm a diesel might just be a step too far!
I’m coming from a Fiesta ST. In all my years I’ve only had one diesel and I really hated it. Swore never to go back there again. Also my mileage is pretty low with most drives no more than 10 miles which would worry me. Do they suffer from short runs like many diesels with dpf issues and the like?
I can see some benefits. There are plenty of them about and generally they seem cheaper than the petrols. Same 200bhp as the 250 petrol and similar 0-60. Fuel economy does look good. And I can imagine that plenty of low down torque might suit a car like the SLK especially with an auto box.
It does seem wrong!
But it wouldn’t be difficult to go and try one so yeah!
I’m coming from a Fiesta ST. In all my years I’ve only had one diesel and I really hated it. Swore never to go back there again. Also my mileage is pretty low with most drives no more than 10 miles which would worry me. Do they suffer from short runs like many diesels with dpf issues and the like?
I can see some benefits. There are plenty of them about and generally they seem cheaper than the petrols. Same 200bhp as the 250 petrol and similar 0-60. Fuel economy does look good. And I can imagine that plenty of low down torque might suit a car like the SLK especially with an auto box.
It does seem wrong!
But it wouldn’t be difficult to go and try one so yeah!
ChrisH72 said:
Hmmmmm a diesel might just be a step too far!
I’m coming from a Fiesta ST. In all my years I’ve only had one diesel and I really hated it. Swore never to go back there again. Also my mileage is pretty low with most drives no more than 10 miles which would worry me. Do they suffer from short runs like many diesels with dpf issues and the like?
I can see some benefits. There are plenty of them about and generally they seem cheaper than the petrols. Same 200bhp as the 250 petrol and similar 0-60. Fuel economy does look good. And I can imagine that plenty of low down torque might suit a car like the SLK especially with an auto box.
It does seem wrong!
But it wouldn’t be difficult to go and try one so yeah!
Coming from a Fiesta ST and doing low miles, then you are right the diesel would not suit you. Otherwise, somehow that diesel does work in the SLK (I have to grudgingly admit).I’m coming from a Fiesta ST. In all my years I’ve only had one diesel and I really hated it. Swore never to go back there again. Also my mileage is pretty low with most drives no more than 10 miles which would worry me. Do they suffer from short runs like many diesels with dpf issues and the like?
I can see some benefits. There are plenty of them about and generally they seem cheaper than the petrols. Same 200bhp as the 250 petrol and similar 0-60. Fuel economy does look good. And I can imagine that plenty of low down torque might suit a car like the SLK especially with an auto box.
It does seem wrong!
But it wouldn’t be difficult to go and try one so yeah!
It does sound like the 250 is probably the one most suited if you are not concerned about the lack of power/torque compared to the V6. I also take it that the ST was manual.
It takes some getting used to, coming from a light manual hatchback to a heavier auto. You get used to a different driving style - less urgency and throttle lag.
With the petrol in manual mode (I presume it has this, I haven't checked) then at least you have instant throttle response.
I had an R171 SLK55 and used to regularly swap with a mate who had an R171 350.
The 350 was a tatty example, with a plethora of faults, which I'm sure were specific to that one and its prior owner(s) but it never felt keen to push on and was much more suited to cruising along slowly.
I would echo others comments about the SLK55 and loved mine. No faults other than a headlamp in 20k miles over 7 years.
Whilst the 250 diesel works well on a spreadsheet, I think the sound of a diesel engine with the roof-down would ruin the experience, particularly if the V8 is an option.
The 350 was a tatty example, with a plethora of faults, which I'm sure were specific to that one and its prior owner(s) but it never felt keen to push on and was much more suited to cruising along slowly.
I would echo others comments about the SLK55 and loved mine. No faults other than a headlamp in 20k miles over 7 years.
Whilst the 250 diesel works well on a spreadsheet, I think the sound of a diesel engine with the roof-down would ruin the experience, particularly if the V8 is an option.
We have literally just px'd my wife's SLK200, had it for 4.5 years with no problems....until we came to change it, then it through an ABS sensor, but that is literally the only issue we had with it. It was a rare manual, in grey. A very nice comfortable car, nice to drop the roof on and go for a drive. Did exactly what it said on the tin really and I'd have another one without any concerns.
Is now currently up for sale by the company we px'd it too.
Is now currently up for sale by the company we px'd it too.
I went to have a look at a 250 today. Unfortunately didn’t get a drive as despite having called in advance the car was shut away in an indoor showroom and clearly wasn’t going anywhere. The staff weren’t particularly helpful and really just stood and watched as I had a poke around the car. Never mind, it did give me the chance to sit in and have a good look.
In short, I really like it.
Nice styling, very good interior quality and all the controls feel nice to the touch. Decent boot space with the roof raised and I thought the roof mechanism was pretty good.
Although I didn’t drive it, I’m sure the 4 pot 250 would be absolutely fine. Many people complain about the 1.6 in the Fiesta but I like it a lot. I’ve kind of gotten used to the turbo now and quite enjoy having a bit of low down grunt. I did read that the 250 isn’t far off the V6 in terms of torque and that it actually sounded pretty decent. At the moment it’s looking good and performance should be at least as quick as the ST albeit in a slightly different way.
Having an auto would be a new experience for me. I’ve never really wanted one but again it would be different. And different can be good. It probably suits the SLK as nearly all of them are auto. One review mentioned the manual was very good but the ones I’ve seen for sale are 200’s. There’s just one 250 manual for sale so they do exist.
Of course there is always the Z4 28i which can be had with manual or auto and has a little more power. But at the moment I’m liking the style of the SLK a little more, it’s a classy thing imo.
A V8 is intriguing. I can imagine they sound fantastic and feel pretty special. The downside of course is that they are twice the price and I must admit to being a bit scared of potential running costs.
I’ll get some drives in quite soon as I have some time off coming.
In short, I really like it.
Nice styling, very good interior quality and all the controls feel nice to the touch. Decent boot space with the roof raised and I thought the roof mechanism was pretty good.
Although I didn’t drive it, I’m sure the 4 pot 250 would be absolutely fine. Many people complain about the 1.6 in the Fiesta but I like it a lot. I’ve kind of gotten used to the turbo now and quite enjoy having a bit of low down grunt. I did read that the 250 isn’t far off the V6 in terms of torque and that it actually sounded pretty decent. At the moment it’s looking good and performance should be at least as quick as the ST albeit in a slightly different way.
Having an auto would be a new experience for me. I’ve never really wanted one but again it would be different. And different can be good. It probably suits the SLK as nearly all of them are auto. One review mentioned the manual was very good but the ones I’ve seen for sale are 200’s. There’s just one 250 manual for sale so they do exist.
Of course there is always the Z4 28i which can be had with manual or auto and has a little more power. But at the moment I’m liking the style of the SLK a little more, it’s a classy thing imo.
A V8 is intriguing. I can imagine they sound fantastic and feel pretty special. The downside of course is that they are twice the price and I must admit to being a bit scared of potential running costs.
I’ll get some drives in quite soon as I have some time off coming.
Gassing Station | Car Buying | Top of Page | What's New | My Stuff