For generations, the wholesome little Mazda MX-5 has largely owned the roadster market when it comes to low costs, piles of top-off fun, performance thrills through lightweight engineering, and fuel economy galore. With two seats, four cylinders, five or six manually-shifted gears, and no BS, the MX-5 is one of the world’s most successful sports cars – and it looks like a solid used convertible buy where reliable long-haul operation is concerned, too.
But what if your needs in a new-to-you two-seater drop-top are a little more posh? Sophisticated? Classy? After all, the Miata isn’t chocolate: it can’t make everyone happy. And though Mazda’s popular roadster is a lot of things, German luxury roadster isn’t one of them.
When shoppers looking for a used drop-top place the emphasis on sophistication, luxury and the desire to flaunt an upmarket badge on the hood, machines like the Mercedes SLK and BMW Z4 may just be the order of the day.
Like the Miata, this pair of high-class convertibles pack two seats, rear-wheel drive, and lightweight motoring thrills – but unlike the Mazda, they’re trimmed with luxury accoutrements, available with higher-output engines, and styled to communicate their driver’s classiness to everyone nearby.
Here’s a closer look at this pair of used Beverly Hills Miatas, and how to shop smart for the one you’re after.
BMW’s frisky little Z4 packed distinctive looks, new features, and a great new cabin in its new-for-2009 model generation. With a motorized hard-panel roof, graceful and curvaceous body, high-contrast cabin and a selection of engines topping out in the ‘35is’ variant with 335 twin-turbo horsepower, this roadster was as fast as it was beautiful – though larger owners report some fuss getting in and out of the otherwise adequately sized cabin. Good mileage (especially from the late-availability four-cylinder turbo engine in the ‘28i’ variant) and lightning-fast shifts from the available seven-speed dual-clutch transmission round out the package.
Avoid a model with the up-sized wheels if your locale has plenty of rougher roads, as they can reduce ride quality. Some models offer a manual transmission, but most will be automatic.
The Test Drive
Be on the lookout for cracked wheels, peeling paint, and signs of moisture or condensation inside of light housings, before hopping on board. Note that a cracked wheel may still hold air, and that a crack may be on the hard-to-see inner portion of the wheel rim. Here’s a good ride to have a mechanic inspect on a hoist.
A weak battery may lead to issues such as non-functionality of the convertible top, and fussy operation of other systems. Keep your new-to-you Z4 hooked up to a battery trickle charger when you’re not driving it for a few days, to reduce the likelihood of electronic issues.
A mechanic should look for blown shocks (you may hear these on a test drive, or feel them via excessive bouncing on rough roads), as well as a bad high-pressure fuel pump and associated hardware on earlier models with the twin-turbo engine. This well-documented issue can cause numerous problems, including Check Engine lights, which make it easier to detect.
Clumsiness from the dual-clutch transmission may be remedied with a transmission software update, but be sure that’s the case by chatting to a BMW service advisor for advice. Confirm that the heated seats both work as expected, and be sure there’s no unwelcome noise from the rear of the vehicle during low-speed turns, which could indicate a relatively rare but notable problem with the differential.
Finally, note that failed convertible roof operation that isn’t battery-related may be fixed with some new micro-switches, or a roof system reset. Be sure to run the roof through its paces several times on your test drive, with an eye for issues.
Benz’s smallest two-seat roadster packed turbocharged four-cylinder power, or a 3.5L V6 in mainstream versions of its latest model, which launched for model-year 2012. With styling more closely matched to other Mercedes models and an appearance more blocky and edgy than the swoopy Z4, it’s a distinctive machine, with no shortage of selection. The four-cylinder engine was punchy, got great mileage, and could be had with a manual transmission. The 3.5L V6 should turn in more power than most drivers need. A fire-breathing, V8-powered AMG version, called the SLK 55 AMG, was available, too.
Feature content included high-tech safety features like Attention Assist, which detects drowsy driving, a Magic Sky roof system, which replaces the convertible top’s main panel with a transparent piece that can be tinted at the touch of a button, and full multimedia connectivity, navigation and more. On-board space and at-hand storage are generous by roadster standards.
The Test Drive
Here’s another candidate for battery trickle charging when you’re parking it for days on end. Like the Z4, the SLK has various systems that get fussy in the presence of weak battery. Add fifty bucks to your budget for a quality trickle-charger, and use it.
Any stuttering, inconsistent performance or a sensation of an engine misfire could be the result of a bad engine-control sensor, some of which will cause a Check Engine light. If that light or any of these issues is apparent, a Mercedes dealer can scan the SLK’s electronic brain to see what the problem is. Also, like the Z4, the number-one culprit for a non-functioning roof is a poor battery charge.
Scrutinize the condition of the roof panels, especially for signs of small, fine cracks in the paint and plastic, which numerous owners have reported as the SLK ages. This is often called crazing. Some owners have also reported roof leaks, which may be evidenced by a musty smell inside, dried-up segments of seat leather that look like beef jerky, and moisture or mold in the carpeting. Visit a coin-op pressure washer with your used SLK candidate and get it good and wet, then investigate for leaks.
As time goes on, be sure to confirm that roof seals are present and intact, plump and properly lubricated, and that all panels are adjusted to spec, with the help of your local dealer.
General Helpful Tips
This pair of roadsters was available with each manufacturer’s version of a central command console, with the BMW’s iDrive system, and the Benz’s COMAND system allowing drivers to manipulate hundreds of functions on a central screen via a console-mounted knob selector. Spend some time playing with the system on each (if equipped), confirming all buttons, knobs, displays and associated functions work as intended. Crashing, lagging, or non-functionality could require a system reset (free) or new electronic hardware (expensive).
Check the Roof
Modern convertibles like these tend to be linked to a sensor and warning system, which will typically display a warning message if something is wonky with the roof. Be sure to run the roof of each model through its paces several times, checking for warnings in the dash. Pause roof operation halfway, when all components are exposed, and look for signs of damaged paint, wear, worn or missing rubber seal segments, and other potential issues.
As sporty rides, there’s a good chance the used Z4 or SLK you’re considering has had the bejesus driven out of it. What are sports cars for, after all? Just be sure to approach any used model you’re considering assuming it will need new tires and brakes, until your mechanic proves otherwise.
Certified Pre Owned (CPO)
Purchasing a used Z4 or SLK via a dealer CPO program can add confidence to your purchase – as CPO vehicles typically undergo intense inspections, have all recall work completed, are better reconditioned, and are often familiar to the selling dealer. Additionally, many CPO models offer available extended warranty coverage.