Alican1

Guys,

I know that these 2 cars are very different, I currently own a 2003 SL 55 and I purchased it for a daily driver.

It is too much car for the West Coast Street and I am looking to trade it in for a 645 BMW.

The 645 is not in the same level as the 55 but I need a regular car and the 55 is not.

Am I making hte wrong move here ?

Alican 1

Xeon

are you looking at the convertible? if you are looking at the coupe, doesnt your DB7 does the job?

A bimmer will always be a bimmer...an AMG will always be an AMG...and of course.. an Aston Martin will always be an Aston Martin

Bob718

You should just get the SL500 or CL500 then. IMO, the 645 is really hideous.

Alican1

I had a DB 7 and candidly it ended up in the shop for the most part of the owner ship.

They replaced brakes, transmission, cluthc, supercharger, A/C unit and had I kept it they wanted ot replace hte tranny again.

So I keep away from Astons, great looking car, but for me not worth the problems.

I am hearing somenegetives about the bimmer the suggestion of moving to a CL or an SL may be a sounder move .

Alican1

ChrisB

I'm puzzeled by you comment of SL55 being too much car.

What part of Vancouver do you live in?

Do you not get out on th open road often?

I've been thinking of a R230 SL55 or SL600 in the future for the novelty of a bit more power.

CASL55

Here's a comparison of the two cars I posted on another BB last summer when I bought my SL55.

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I’ve had a deposit in on a 645 for about two years, so I’ve been at the front of the line for ordering for months, but I haven’t pulled the trigger because of the unavailability of features that are important to me. I don’t like voice nav instructions, and the 6er doesn’t have the nav instructions appear in the tach like the 7er, but way over on the right hand side of the iDrive, which I think is unsafe, so I wanted the HUD. Originally the HUD was going to be available for June builds, but it’s now scheduled for the 2005 cars. I also wanted satellite radio, and for that I need to wait at least until I can get a September-build vehicle. I was also put off with phone integration issues and the general unreliability of early production vehicles (I had a 2002 745i). So I was looking at getting a vehicle built in September, and probably taking delivery on it in November (I’m on the west coast). That seemed like a long time.

Depressed, I started snooping around on eBay and saw a new 2004 SL55 for sale, and, in a moment of impulsiveness, I bought it. It has the nav instructions under the speedo and the tach, kind of like the 7er, and it has satellite radio and a well-integrated phone available now. It’s also got nearly a 2 year production run behind it.

It fills the same automotive niche for me as the 6er, but it is also quite different: more powerful, less carrying capacity, more luxuriously appointed, automatic transmission only, able to switch between being a coupe and a convertible in 16 seconds, and more expensive. Both cars provide sporting transportation for two adults and have the road manners and appointments of touring cars, rather than rawer-edged sports cars. Other cars in this category are the Jaguar XKR and XK8, the SL500, and the Maserati Coupe. I’ve driven the XKR and found it pleasant, but less involving than either the Merc or the BMW. I’ve not driven the Maserati or the SL500. I’ve owned two 911s. I wouldn’t put any of these cars in the same class as a 911, but a 911 is too noisy and confining for me at my advanced age. There’s another car that might be considered to fall in this class: the Bentley (VW) Continental GT. It’s a lot more expensive than any of the others. I’ve never even seen one, and I have a hard time getting my head around the idea of a 5500 pound car with sporting pretensions; it has taken me a while to make my piece with the 4400 pound SL55. There’s also the Aston Martin DB9. The Maserati, Bentley, and Aston are all too exotic for me: I don’t want to drive 100 miles for service, or be stuck in Wyoming 1000 miles from the nearest dealer.

What follows is a comparative review of the 645 (with the sport package) and the SL55. Well, it’s mostly about the SL, but with the 645 taken as a point of reference. It’s based upon my two weeks of ownership of the SL55, and a far amount of time spent in dealers’ 645s and 545s, plus general BMW knowledge from owning a 745 and a 540i 6-speed with sport suspension.

Power. One of the big differences between the two cars is the SL55s power. Because of the supercharger, you don’t have to wait for high rpms to get your back pressed into the seat. With fewer than 9 lbs per horse to the 6er’s a little under (coupe) or over (cab) 11, the SL has significantly more grunt, even when saddled with (oink) a whole lot of weight. Manufacturer’s 0-60 mi/hr time is 4.5 sec for the SL, vs 5.5 to 5.7 for the 645. The SL punches a smaller hole in the air, so the difference widens as speed increases.

Handling and suspension. The Mercedes feels lighter than it is, but it’s still obvious that this is a heavy car. The SL55’s primary cornering attitude is mild understeer, with as much oversteer as you’d like available at the command of your right foot, at least until the ESP (Mercedes’ name for what BMW calls DCS) steps in. The AMG folks have done a great job of getting the ESP to resist calling a halt to the festivities until much later than BMW has done with 645 DCS. I always turn DCS off for spirited driving in a 5er or 6er, but I leave it on in the Mercedes. It’s nice to know it’s there to save me from myself if I overcook it mildly. On a track, I’d probably want it off in either car; it would be nice to drive both on a track and find out.

Turn-in in the SL is somewhat lethargic compared to the BMW, and much more so when compared to a sports car like a 911. At first I was missing apexes by six inches to a foot. The active steering in the BMW makes the turn-in seem better than it is, and that’s a good thing. Once persuaded to get into the corner, the SL hunkers down and takes a nice solid set. It’s a confidence-inspiring car in a corner, but not as lithe and alive as the 645. The active body control serves to reduce roll in a corner like BMW’s trick with twisting the torsion bars, and both seem to do a fine job. Both cars offer sport suspension modes. You have to push the SL pretty hard to feel much difference. The SL offers ride height variation with speed, and two higher-than-normal settings to help you keep from scraping the front spoiler entering driveways.

The ride is good for a car that corners so flat. The absence of run-flat tires keeps small road imperfections from being transmitted to the interior as much as they are in the 645. For larger, lower-frequency variations, the two vehicles ride similarly.

Transmission. The 6er has three transmission choices while the SL only has one, a torque-converter manumatic with console and steering wheel shifters. Latency between activating the paddles and the shift actually occurring is between the fairly slow BMW Steptronic transmission and the reasonably rapid 545/645 SMG. The difference is important. I find it frustrating to use the Step in manual mode, and end up not using it much at all. It’s easy to anticipate the shifts slightly on the SL55, and I use the manual mode whenever the road gets the least bit twisty. The BMW active steering ensures that your hand never have to leave the 9:00 and 3:00 positions on the wheel, so if you’ve got SMG, no matter how tight the corner, you’re hands are always in the right operate the paddle. To shift the SL55 in the middle of a tight corner you have to move your hands. In practice, it’s not a problem, since, unless you screw up, you do your downshifting before you’ve cranked the wheel over, and your upshifting after it’s nearly centered. With SMG, you can tap the paddle twice in quick succession and get a double downshift, while with the Step and the SL55 auto, you must go through the gears in sequence. Manual mode really lets the driver pick the gears to the point of letting the engine bounce off the rev limiter if you shift too late, but will upshift automatically to keep the engine from lugging, like SMG and Step. In the auto mode, the transmission is supposed to have lateral acceleration sensors that let it know when you’re in a corner, and then it’s not supposed to downshift. That would be a good thing. I haven’t had the nerve to stand on it in a hard corner to see if it will downshift, but I can attest to the fast that it will do so in a mild (like 0.3 or 0.4 g) corner. The SL55 has only a five-speed box, and the gap between 2nd and 3rd is too large. When you have paddle shifters like in the SL55 and the SMG 6er, you shift a lot more, and closely-space gears are a fine thing. I think the move to a seven speed box for the upcoming M5 and M6 is a good move on BMW’s part. There’s a nice feature in the SL for passing: in any mode, if you move the transmission lever to the left and hold it there for a second or so, the transmission looks at how fast you’re going and downshifts to whatever gear will give you the most acceleration when you mash the throttle.

Interior appointments and comfort. The SL is impeccably appointed, to the point of having alcantara-covered headliner and windshield pillars. The gauges are jewel-like, especially at twilight. The pedals, including the dead pedal, are stainless steel with grippy little rubber bumps. The 645 is, well, minimalist; some would say Spartan for a vehicle in its class. The Mercedes seats have far more adjustability than the BMW sport seats. Ventilated seats are available for hot climates on the S, but not on the 645. Oddly, the illuminated door sills that are standard on the 645 are an option on the SL55.

With the top up, the SL is quiet, maybe slightly quieter than the 645 Coupe and a lot quieter than the 645 Convertible. Top down, the wind deflector (mounts to the roll bar, and included, not an accessory as on the 645) on the Merc works well, and, in spite of the warnings not to do so in the manual, it’s easy to reach back and flip it up or down as conditions change. The Logic 7 sound system on the 645 sounds better than the Bose system on the SL. In summary, the SL is aimed at a higher price point that the 6er, and it sure shows when you’re inside the car.

CASL55

Controls. BMW has iDrive, and Mercedes COMAND. In each, there’s a knob you twist to highlight menu items, and push to select them. In concept, they’re not that far apart. Mercedes has a keypad that you use to dial the phone or select radio stations, but, strangely, not to enter street numbers into the Nav system. In the Mercedes, to select major systems, you push a dedicated button instead of pushing the iDrive knob up and down or right and left. The menus are a little flatter in the Mercedes: CD, Satellite Radio and AM/FM radio (push again to change bands) are all top-level items, instead of being located under Entertainment as in the BMW. And then, across the top of the display, there are a row of buttons for frequently-used functions that apply to particular systems, mostly nav, whether or not they’re currently selected: mute, zoom the map in and out, get nav info, etc. The buttons make the Merc system easier to learn and faster to use for some actions, but the tradeoff here is that all these buttons take up room, and thus the display is smaller than the Bimmer’s. The Mercedes buttons are also not tactilely differentiated, and require you take your eyes off the road more than in the BMW until you learn them by feel. That’s a strange omission, given that the SL’s steering wheel buttons offer more tactile differentiation than the BMW’s. The Mercedes has a pretty comprehensive pair of secondary displays under the speedo and the tach, like the displays in the 745 and 760, but containing more information. Thus it’s not necessary to look at the main LCD display to see the trip computer output, what phone number is being dialed, what radio station is playing, and a lot of other things. The voice-recognition based controls on the SL work just fine with the top up, and acceptably well with it down. The SL does have a “Lawyer’s Screen” that flashes briefly when the key is turned, but it goes away all by itself, unlike the similar screen on the 545, 645, and 745.

There’s one control on the 6er that works much better than its counterpart on the SL, and that’s the turn signal lever. The Merc’s is conventional, and every time I cancel it by forcing the lever back to the center rather than gently pushing the lever the same way I did to start the turn signal, I’m struck by the crudeness of the old way.

Exhaust note. They both sound great. The SL’s is deeper and the BMW’s more crackly. With the combination of the torque converter on the trannie and the deep exhaust note, the Merc can sound a little like a big powerboat off the line, which in my mind is not a great association. The SL’s exhaust burbles nicely on compression braking, but I prefer the 645 sound going down a hill. I think the four pipes are a bit over the top, but BMW is doing that on the M-cars, so it seems to be the fashion.

Brakes. The SL has brake-by-wire, which has received a lot of bad press in the automotive journals for having an artificial feel. The feel is entirely artificial, in the sense that it’s generated in response to some computer somewhere controlling the relationship between pedal travel and force applied to the pedal, but under most circumstances, it feels reasonably natural. I found it weird at first, but after a couple of weeks have gotten used to it, and I don’t mind it any more. Having brake-by-wire gives the car the capability of sensing lateral acceleration in a corner and applying more braking to the outside (weighted) wheels and less to the inside (unweighted) wheels without letting things go so far that inside wheels start to slip and the ABS kicks in. You have to be pretty seriously into trail-braking for this to make a difference. Another brake-by-wire feature that Mercedes has implemented in the SL and a lot of their current lineup, is an Orwellian “I, the car, think that the driver is trying to do a panic stop but not pressing hard enough on the brake, so I’m going to take control and stand on the sucker” behavior, and you can’t turn it off. Mercedes has all kinds of studies saying that your average driver doesn’t hit the brakes hard enough in panic stops. This may be true, but I would expect your average SL55 driver to be more in control of his or her vehicle. I was prepared to hate this intrusive braking “enhancement”. I still don’t like the idea, but I have not set it off accidentally, even driving aggressively and trying to trick it. It apparently looks at how fast you come off the accelerator and how hard you initially apply the brakes to decide when to intervene. I wouldn’t call me a convert – the idea still makes me nervous – but I’m no longer scared of it. The BMW has very nice conventional brakes, and there’s a lot to be said for the absence of unnecessary complications.

Seeing out. The blind spots are small in the 645 coupe and the SL, and only slightly larger in the 645 cab. It’s hard for me to tell where the corners of the 645 are, especially the rear ones. I had the same problem in the 745, and it made parking difficult. I would want PDC on any of the high-trunk BMWs but it’s unnecessary on the SL.

Space. The SL has a tiny trunk. When the top’s down it covers the luggage area. There’s a button in the trunk that, when pressed, moves the folded top out of the way. That’s an expensive solution for a relatively minor problem, and that thinking is typical of the engineering on this car. Another example: it’s hard to put stuff in the storage area behind the seats. Other cars have a mechanism that allows the user to release the back of the seat, and the seat moves forward on its track to make room. The Mercedes has a switch on the back of the seat. Press the forward-pointing arrow, and the seat slides forward while the back folds under the control of a motor that there for only that purpose. Press the backwards-pointing arrow, and the seat returns to its original position. Can we say “overkill”? The 645 has a huge trunk for its class. The 645 has small, cramped back seats. The SL has no back seats at all. There’s a fitted bag that goes behind the front seats. The Bimmer sure wins this one.

Looks. For all the comments I’m getting, most people find the SL55 to be gorgeous (mine is Brilliant Silver, with AMG Style III wheels). I myself am not totally sold. I like the looks, but with the top up, I don’t think the design is as successful as the 645 coupe with Style 92 wheels (those ellipsoids have got to go). The Mercedes design is certainly more conventional than the BMW, and I think 5 years from now it will look old-fashioned. I understand the engineering reasons why the curve of the SL folding top has to be a constant radius so it can fold inside itself, but I’d like to see the aft end of it feather more smoothly into the rear deck. I think the SL looks very nice with the top down. There’s one silly design touch that’s grown on me: the vents between the front wheels and the leading edge of the front door. They remind me of the 300SL, which is undoubtedly the point.

Value for the money. The SL is a very expensive machine. You can see where the money went -- in the appointments, the power, the lavish engineering, but it’s hard to say that it’s a good value. The 645 is chock-full of features at a much lower price, and, even with its minimalist interior, is a better value; that is, unless you must have both a coupe and a convertible -- in that case, the SL is cheaper than two 645s. In a larger sense, none of the cars in this segment are good values compared to Acura and Lexus sport coupes, but that doesn’t stop enthusiasts from buying them.

Delivery defects and reliability. No problems so far with the SL – 1200 miles and counting. With the 2003’s there were problem with the top mechanism and with rattles from the fuel pump.

Overall. I’m pretty happy with the SL55. It’s got plenty of go. It’s a exceedingly capable machine in a corner. It’s quiet, pampering, and comfortable. It’s pretty. I would prefer to be more tightly coupled to what’s going on with the contact patches, to have quicker turn-in, more direct steering, a little faster throttle response, and less avoirdupois. On the weight issue, it may be that an open car with a big engine, really stiff chassis, lots of soundproofing, many safety features and big crush zones, together with a folding hard top, has to be heavy if built with conventional materials. If Mercedes had, as Colin Chapman used to say, “add[ed] lightness,” by replacing steel with aluminum and carbon fiber, they might have driven the price of an already-expensive vehicle clear through the roof.

Maybe the M6 will be the machine that provides a more sporting experience at a comparable level of comfort and refinement. I’ve got my deposit in, and I’m looking forward to finding out. Maybe what I’d really like is an L6, like an M6 but with upgraded interior appointments.

Jim

Alican1

Alican1

Hi Jim,

Thank you for the response, I had signed onto the 6 series board, and am finding out that the 6 series is not as well accepted as I had originally thought.

There is a link to the New York post with some negetive comments re the new 6.

My love for the 6 started with the fact that like you I have owned several 911's and where as they are great cars, the main problem is no room for golf clubs and it is a more confining car.

I have owned 3 BMW 850's and have absolulty had fun with them , the last one being a 96 850ci. The problem with the car was I needed a fresher interior . So that is where I sold my 911 (96 c4s) and the 850 and purchased the SL.

Mine is an Alabaster white iwht dove interior and the dis AMG 19inch wheels.

I have asked about an M6 but it appears that we will not see one in Canada until 2006 , the dealer is not even taking orders at this time .

Based onsome of hte comments my best deal is to keep the SL 55 .

Thank you for your imput.

Alican 1

CASL55

I think you're right. I don't think the 645 is much more than 3/4 baked at this point, especially if your standard is the 850. What I'd really like, and what it sounds like would serve your needs as well, is a 21st-century 928.

Jim

Twinturbo

I think the M6 is a fairer comparison with the SL55. Performance wise, the M6 would win in every area. In your point of view, it would look like the M6 is the way to go. Did you find the 6 series cab didnt drive as well due to reduced structual strength? And also do you know if they will make an M6 cab? It would be an interesting comparison with the SL55.

Oh, and another question. Is the 6 series lighter than an equivalent 5 series? Interested to see wether the M6 will be faster than the M5. If it is heavier I am sure there would be a small power upgrade in the M6, but it would seem the 6 would be lighter.

a5a80901

hi Alican. If by any chance, you going to sell your SL55. PLEASE LET ME KNOW. I will probalby offer you better deal than delaer .LOL. By the way I lived in Richmond. and U?

-ALEX

Alican1

Hi Alex,

My e mail address is ali@convoy-supply.com.
I live in white rock.
Please email me when you get a chance please .

alican 1

CASL55

SL55 4319 lb
645 Coupe, auto 3792 lb
645 Cab, auto 4189 lb
545 Sedan auto 3748 lb

Source: manufacturers' web sites

Jim

W210

Ali,

If you want a more relaxed cruiser, how about the CLK500/55? Personally, I would even pick a sedan such as the 545i or 745i or A8 or even a Lexus SC430 over the 645i.

Two other interesting cars available in 2005, the M5 and the new S-class.

I don't know, I just find the BMW 6 extremely unattractive, over priced and undesirable. Personally, out of the new BMW designs, the 6 is least of my favourite.

Another option for you, spend a little more and go for the Bentley Continental GT with the civilized ride and AWD practicality in the rain?

ChrisB

Alican1

What year, colour, interior trim, wheels, options do you have on the SL55? Picutres?