SLK55 AMG Economy car?

[SL55]

Just racked up 5k miles in my R172 SLK55 AMG and averaged 27.5 mpg overall. On my daily 20 mile commute I get 32 mpg on typical A and B Surrey/Sussex roads. Best ever was 35 mpg cruising at motorway speed limit. Not bad for a 416bhp 5.5 litre V8. Cylinder deactivation works pretty well. You quickly get used to initiating V4 mode even when pressing on. The stop/start mode must help too.

[WantAnXKR]

I wish my 2010 C180CGI Sport auto (BlueEfficiency lol) would do that much!!!

[Seventy]

Pretty impressive. I am averaging 22 in my C63 over the first 7K miles. I don't have a heavy right foot though and don't do much city driving. The new C class Amg will either have this engine or a 4 ltr one.
I'll tell you what else is impressive. Two posts in nine years!!

[slk 32]

That's impressive

my R171 SLK 55 does approx 17-18 mpg round town and 21-22 longer trips
my R170 SLK 32 does 22-25 around town and 28 on a longer trip

[akeithj]

SL 55 very impressive, can you share some of your other impressions during your first few months of ownership?

[Defcon5]

SL55 said:

. You quickly get used to initiating V4 mode even when pressing on

Do you have to activate it then? I was under the impression it was supposed to be seamless

[SL55]

akeithj said:

SL 55 very impressive, can you share some of your other impressions during your first few months of ownership?

After a couple of C63s and an SL63 the throttle response is not quite so good especially going from the overrun to back on the throttle when it tends to go from V4 to V8 and change down a couple of gears all at once. So not quite so smooth as my Bentley Continental GT V8 which is truly seamless. Also, anybody expecting the fruity exhaust of the C63 will be disappointed but in the real world it is unobtrusive and therefore more relaxed even when pressing on.

[SL55]

Defcon5 said:

Do you have to activate it then? I was under the impression it was supposed to be seamless

No, it is entirely automatic but you quickly learn how to initiate the V4 mode by lifting off slightly with a commensurate improvement in economy. It is amazing how fast one can go on four cylinders!

Gosh! I've just doubled my number of posts after nine years of lurking. Must try harder.

[tonys]

SL55 said:

Just racked up 5k miles in my R172 SLK55 AMG and averaged 27.5 mpg overall. On my daily 20 mile commute I get 32 mpg on typical A and B Surrey/Sussex roads. Best ever was 35 mpg cruising at motorway speed limit. Not bad for a 416bhp 5.5 litre V8. Cylinder deactivation works pretty well. You quickly get used to initiating V4 mode even when pressing on. The stop/start mode must help too.

I'm sure a Prius driver could also match those figures if he/she tried hard enough, which just proves that an SLK55 should be the new eco-warrior's car. Well done that man

[crazy about cars]

Very nice! Test drove a 2012 and loved it! Just waiting for them to depreciate bit more

p/s: top lurking btw!

[akeithj]

For those of us who do not require 4 seats, the SLK 55 would seem to be a better option than the C63, as you have very similar performance, but far superior economy and you get the benefit of a folding hard top.

[mo_han]

Recently on a 40min motorway cruise, I managed 30.7mpg in my R171 SLK55. For such a big engine, it amazes me how economic these types of cars can be.

[SFO]

AMG V8s can be 'economical' ..

W208 CLK55:






W219 CLS55:

[Catpuddle]

I saw 19.5 mpg on a 50 mile mixed trip in my SL55 the other day - I wasn't driving economically, plenty of stop start driving and some use of the right foot. I also had the lid down for half the journey. Not bad for a 500 horsepower beast, and a lot better than I was expecting.

[Ari]

You guys relying on the OBC?

On my second Merc, first one the OPC over read by about 10% so a claimed 33mpg was barely 30. On current car it's virtually spot on however.

Might be worth doing some proper calcs just to see how accurate yours is.

[crazy about cars]

Hmm just saw this nice example : http://classifieds.pistonheads.com/classifieds/use...

I am just not too sure about the nearside rear exhaust. Just look s a little wonky...

[kryten22uk]

crazy about cars said:

Hmm just saw this nice example : http://classifieds.pistonheads.com/classifieds/use...
...

Erm that's an SL, whereas this thread is about SLK.

[crazy about cars]

kryten22uk said:

Erm that's an SL, whereas this thread is about SLK.

whoops ... sorry about that Might have had couple of drinks :P