First introduced in 2000, the RS4 has evolved into one of Audi's most iconic nameplates, despite being available for short periods of time with each generation. First offered between 2000 and 2001, it returned for 2006-2008, and then again for 2012-2015. Each time as a station wagon, but Audi made an exception and offered a sedan between 2006 and 2008. Come 2018 and the Audi RS4 returns for the third time, again in the Avant body styles. But this time around word has it that Audi is also planning to revive the short-lived four-door sedan, which may also return to the United States. While the German firm is mum on the matter, I put together a speculative review with what it may bring to the table.

The fact that the RS4 sedan didn't return after 2008 is a bit shocking if you ask me. Audi is super competitive in just about every niche and it's even trying to create its own, but for some reason it doesn't really want a piece of the action where BMW and Mercedes-Benz are making the big headlines. The decision to offer the RS4 as a wagon only seems strange to say the least with Audi's latest competitor for the BMW M3 and Mercedes-AMG C63 dates all the way back to 2008. But apparently Audi is finally coming to its senses and a new RS4 sedan might be just around the corner.

Updated 10/02/2017: We updated the speculative review with a new rendering and new information. Check it out below.

Continue reading to learn more about the upcoming Audi RS4 Sedan.

Exterior

The RS4 sedan may seem like a mystery just now, but it really isn't. Just take the more aggressive cues of the RS4 Avant and slap them on the A4 sedan and you get the real deal. And it's exactly what this rendering provided by X-Tomi Design is all about.

Up front, we can see the RS-style honeycomb grille, as well as the "quattro" lettering underneath the license plate and the "RS4" badge on the mesh. Below, there's a sportier bumper with larger air vents, both of which have the same honeycomb grille. The thin intake just below the main grille is finished in black, with the lower element designed to look like a splitter. The rendering also includes the the Matrix LED headlamps with tinted bezels, which are optional on the RS4 Avant and should be offered on the sedan too.

Moving onto the sides, we can see more of the features that debuted on the RS4 Avant. Specifically, the sedan has slightly beefier fenders, which should be 1.2 inches wider in production form, RS-style mirror caps finished in black, and larger wheels. New-design 19-inch, forged aluminum wheels should be standard, with 20-inch rollers available on the options list. The sportier side skirts and the lowered ride height also contribute to the sedan's slightly more menacing profile.

It's around back where the sedan will be different compared to the already familiar RS4 Avant. But aside from the three-box design with an actual decklid, look for similar performance features. A big spoiler should highlight the trunk lid, while the bumper should include a sporty diffuser with large, oval exhaust pipes. The "RS4" badge on the tailgate will round off the rear fascia.

Audi also introduced a new paint option for the wagon. It’s called Nogaro Blue, it features a pearl effect, and its a throw-back to the first-generation Avant from 1999. We think that this Audi Exclusive option will also be offered on the sedan, so it's why our rendering is finished in the same hue.

Interior

The interior of the RS4 sedan should be identical to that of the Avant model from the dashboard toward the second-row seat. As usual, almost everything but the seat, which can ordered in various colors, will be finished in black. That's because Audi seems to think that black "underscores the sporty character" of an RS can better than any other color, but I'm not a big fan to be honest. Audi should at least offer an option to to have the dashboard, door panels, and center console in a more livery color. Not necessarily a flashy shade of blue or red, but at least brown or even gray.

Speaking of features that you can have in a different colors, there's light-colored leather for the seats and door armrests, and grey carbon trim for the dashboard and center console. As seen in the Avant, the front seats are Audi's latest RS Sport units with aggressive side bolstering for proper support during spirited driving. The optional honeycomb pattern introduced on the Avant should be offered on the sedan as well.

The flat-bottomed, RS-style steering wheel will also be wrapped in leather and complemented by white stitching and the usual "RS" badge. The latter will also adorn the shift gate and the illuminated door sills that should come standard with the car. There should also be an RS-specific display in the instrument cluster that indicates g-forces, tire pressure, and torque on top of the usual information you get in the more mundane A4 sedan.

Expect the sedan to benefit from the same options as the station wagon, including the styling packages that add carbon-fiber with aluminum or black accents. The Audi Exclusive program will handle any other special request for customers willing to invest a bit more in their RS4.

Of course, all of the above will come with a significantly smaller trunk due to the sedan body styles, but less luggage room will mean better dynamics and performance.

Drivetrain

If there's one big change to talk about, it's the engine. The RS4 Avant ditched the previous 4.2-liter V-8 for a newer, 2.9-liter V-6 and this is the same mill you will find under the hood of the RS4 sedan. The twin-turbocharged unit generates 450 horsepower and 443 pound-feet of torque, which is the same as the V-8 in terms of horsepower, but with an extra 126 pound-feet of torque.

The added torque and the fact that the new RS4 Avant is 176 pounds lighter that it's predecessor, give the wagon a 0-to-62 mph sprint of only 4.1 seconds. I guess it's safe to say that the sedan will be a tad quicker and hit the benchmark in four seconds flat or maybe even 3.9 clicks, which is more or less on par with competitors like the BMW M3, Mercedes-AMG C63, and the Cadillac ATS-V. Top speed should remain locked at the usual 155 mph, but the optional RS Dynamic package will lift the limit to 174 mph.

Just like in the wagon, the engine should mate to a Quattro all-wheel-drive system and an eight-speed Tiptronic automatic transmission, both with significant upgrades compared to the outgoing model. Optionally, Audi will offer a rear sport differential. The options list will also include an RS Sport suspension with Dynamic Ride Control, ceramic brakes, and RS dynamic steering.

Average fuel consumption is rated at 8.8 liters per 100 km and it should remains about the same in the sedan. This converts to 26.7 U.S. mpg, but the official EPA ratings should be different. Either way, expect the sedan to boast an efficiency gain of around 17 percent over the outgoing RS4 Avant model.

Prices

When it hits dealerships, the RS4 will become the most expensive version of the A4 sedan. A lot more expensive than the base model actually, just like the RS4 Avant comes with a €46,100 premium compared to the entry-level A4 Avant. That's €79,800 in Germany. Given the 136.8 percent premium and the base A4's €31,850 sticker, it's safe to assume that the RS4 sedan should start from around €75,400. Should it come to the U.S., expect it to cost somewhere between $65,000 and $70,000 before options.

Competition

BMW M3

Arguably the most celebrated compact performance sedan, the BMW M3 is the car to beat in this niche. Although it's already four years old as of 2017, the M3 is far from dated, unless you're really picky about the company's current interiors, which aren't quite as fresh as Audi's or Mercedes'. The German sedan's exterior is downright sporty and it's enhanced by a drivetrain that delivers solid performance on both the road on the track. The turbocharged, 3.0-liter inline-six unit is rated at 425 horsepower and 406 pound-feet, figures that aren't as spectacular as the RS4's. However, you shouldn't let that fool you, because the M3 is quite fast from a standing start. While models equipped with the manual transmission hit 60 mph in 4.1 seconds, sedan fitted with teh dual-clutch automatic need on 3.9 ticks to hit the benchmark. And of course, unlike the RS4, the M3 can be had with a stick and three pedals, although this isn't possible in the United States. Top speed is capped at the usual 155 mph. German pricing for the M3 starts at €77,500, but the sedan is also available in the U.S. from $65,500.

Read our full review of the BMW M3.

Mercedes-AMG C63

Launched for the 2015 model year, the AMG C63 bring a balanced mix of aggressiveness and elegance to the table. While it looks like a shrunken S-Class, borrowing some of the big sedan's elegance, the AMG-specific parts add a significant dose of sportiness front and rear. The AMG C63 also looks a bit more organic by design, which makes a slightly more exotic proposition than the M3. The Merc shines on the inside too, thanks to its S-Class-inspired cabin with the wide, shiny center console and the multi-layered dashboard. All of this, of course, on top of the premium materials and acres of leather on the seats and door panels. Thing are equally interesting under the hood, where the German sedan hides, unlike it's competitors, a V-8 engine. The twin-turbo, 4.0-liter mill is available in two flavors, starting with the base model that cranks out a solid 476 horsepower and 479 pound-feet of twist. Get the C63 S and output jumps to 503 horses and 516 pound-feet of torque, more than any other competitor in this market. The sprint to 60 mph takes four seconds with the former and 3.9 clicks with the latter. Pricing begins from $66,100 and $73,700 in the U.S., respectively. In Germany, prices come in at €76,398 and €84,668, respectively.

Read our full review of the Mercedes-AMG C63.

Cadillac ATS-V

Not only newer than the M3 and AMG C63, having been launched for the 2016 model year, the ATS-V is also the only American competitor for Germany's finest compact sedan. The ATS itself is a new nameplate and Cadillac smallest vehicle yet, and was designed specifically to compete with the BMW 3 Series, Mercedes-Benz C-Class, and Audi A4. The ATS-V obviously goes against the M3, AMG C63, and RS4, and it has everything it takes to give them a run for their money, except brand prestige of course. The American sedan is also a breath of fresh air design wise, using loads of angular lines and some features inspired by the larger CTS model. The interior is a nice place to spend time in, being just as comfortable and well-equipped as the competition. Of course, the CTS-V comes with the mandatory sport seats, carbon-fiber trim, and the latest technology. Motivation is provided by a twin-turbo, 3.6-liter V-6 that cranks out 464 horsepower and 445 pound-feet of torque. This enables the sedan to hit 60 mph in 3.9 seconds, on its way to a top speed of 185 mph. The latter is a best-in-class figure. The ATS-V Sedan is priced from $60,695, making it the most affordable vehicle in this comparison.

Read our full review of the Cadillac ATS-V.

Brief History

As previously mentioned, the "RS4" nameplate goes back to 2000, when Audi launched the RS4 Avant as a successor to the short-lived RS2 Avant of 1994 and 1995. Produced for only two years, the first RS4 was sold as a wagon only. A brand-new model was launched in 2006, and that's when the one and only four-door sedan was introduced.

Sold alongside the Avant wagon and the two-door cabriolet, the sedan used the same 4.2-liter V-8 as its RS4 siblings. Based on the existing V-8 from the S4, the 4.2-liter unit was rated 414 horsepower and 317 pound-feet of torque. This was enough to give the saloon a 0-to-62 mph sprint of 4.8 seconds, which was pretty impressive at the time. Road & Track actually recorded a 0-to-60 mph sprint of only 4.5 seconds, which made the RS4 one of the quickest sedans available on the market. Top speed was officially capped at 155 mph, but owners reported to have hit 170 mph.

Design-wise, it was a genuine RS car with wider flared front and rear wheel arches, larger front bumper intakes, a diffuser like element, and unique wheels. The optional Optic Pack added a black trim and a black front grille. The options list also included adaptive headlights to complement the standard Bi-Xenon HID lights.

The transmission was a six-speed manual by Getrag that routed power to all four-wheels through a Quattro system.

The AWD had the third-generation asymmetric Torsen T-3 centre differential featuring a 40:60 front-to-rear torque split under normal conditions and a more aggressive Torque Bias Ratio compared to the regular A4.

Production of the second-generation RS4 ended in 2008, a year that also marked the end of the road for the sedan. Although the nameplate was resurrected between 2012 and 2015, the lineup no longer included a four-door sedan.

Conclusion

The fact that the RS4 Sedan may make a comeback is incredible news on its own. Not only Audi needs a proper competitor for the BMW M3 and Mercedes-AMG C63, but the RS4 Sedan is very important vehicle that's missing from both the A4 and the RS lineups. And judging by all the information we know about the new RS4 Avant, the sedan should be at least as good as the competition. The rumor that it may return to the United States makes everything that much better.

References

Audi RS4 Avant

Read our full review on the 2018 Audi RS4 Avant.

Audi A4 Wagon

Read our full review on the Audi A4 Wagon.

Audi RS4

Read our full review on the previous generation Audi RS4 sedan.

Read more Audi news.