THE MANUAL V8 SEDAN THAT ALWAYS GETS OVERLOOKED BECAUSE OF ITS FAMOUS SIBLING
The 2000s was a crazy time for sports sedans, with brands from all over the world throwing their hats into the ring to produce the most commanding family-friendly performance weapons. With vehicles like the wailing BMW E60 M5 and mental Mercedes-AMG C63 on the market, as well as the sure-footed Audi RS4, it was easy for some to fall through the cracks.
This exact scenario played out for the RS4's less-powerful sibling, the S4. It was still a road-holding monster, but it simply never found the notoriety and respect of the range-topping A4-based sedan. Happily, they now represent a great used deal when compared to RS4s, making them a tidy bet in 2026.
The S4 Arrived Before The RS4
When Audi unleashed its third-generation A4 compact sedan in 2005, it wasted no time in offering more potent versions for family gearheads who wanted to enjoy themselves at the weekends. For those not looking to see their wallets blown to pieces by the fuel costs associated with a V8, the A4 could be had with a potent 3.0-liter V6 engine that produced 220 hp. Twinned with Audi's legendary Quattro all-wheel-drive system, the A4 3.0 could manage 60 mph in just under seven seconds, a respectable effort.
The S4 took things to another level though, and arrived alongside the rest of the founding A4 B7 range in 2005. Wanting to ensure the model was as versatile as possible, the S4 could be had in standard sedan, wagon Avant, and even convertible forms, though the drop-top didn't arrive until 2006. Audi manufactured the B7 generation S4 until the B8 came along in 2009, ensuring it didn't get a particularly long production run.
The S4 Was Audi's M3 Rival Until The RS4 Arrived
With the RS4 not coming online until 2006, the S4 was thus the main rival for Audi's key rivals like the BMW E46 M3 and the Mercedes C55 AMG. As a result, Audi didn't exactly cut corners when developing the underpinnings of the S4, with the little sedan getting everything it needed to take it the heavyweights of the compact sports sedan market.
The S4s Performance Was Nothing To Be Sniffed At
Like most high-performance Audis of the period, the S4 was graced with a big 4.2-liter naturally aspirated V8, which was placed out front. To help keep weight down, the V8 was constructed purely from lightweight aluminum, the same material used to produce the majority of the S4s suspension components. Audi's Quattro AWD setup was on hand to ensure none of the V8's 340 horsepower was spun off into the ether, with the grunt channeled to the wheels via either a six-speed manual or six-speed Tiptronic automatic transmission.
With a 0–60 mph sprint time of 5.2 seconds, the S4 couldn't quite match the six-cylinder M3, though it did have to lug around an extra two doors. It may not have been quite as spritely as its BMW foe, but it boasted extra practicality that made it more viable for drivers with friends and family who wanted to come along for the ride.
The Quattro AWD Didn't Have To Work Alone In Keeping The S4 Glued To The Road
The S4 came fully loaded with independent suspension front and rear, as well as an enhanced braking system that helped bring the heavy S4 to a stop. The suspension was stiffened up compared to the standard A4, but was still kept more on the softer side to ensure it would continue to be effective on the road. This meant that it wasn't the most dynamic of sports sedans on the market, especially considering the heavy V8 sat out front.
The front-mounted engine gave the S4 a front-to-rear weight distribution of 60/40, which meant it tended to suffer from understeer when pushed. It offered an engaging drive, though it was more on the cruiser side compared to the likes of the M3, which had a perfect 50/50 weight distribution. With the Quattro system on the go, the S4 also makes a lot of sense for gearheads who enjoy going for a blast in the depths of winter.
The Forgotten S4 Is Worth Surprisingly Little These Days
As a result of the RS4 somewhat stealing its thunder when it launched a year later, the S4 was cast firmly into the shadows. While it may not have been the 'go-to' choice in its period, the B7 S4 represents a great bargain in 2026. According to Kelley Blue Book, a solid example can be had for around $6,000 these days, well less than the $22,000 or so you'll need to shell out for a full-fat RS4.
Given it's set up to be more on the softer side than its more commanding sibling, the S4 is also the better option for those looking to use it as a daily driver. Of course, as is the story with most big-engine sports sedans, there are some key things to look out for before pulling the trigger on a B7 S4.
Timing Chain Failure Can Cause You And Your Bank Balance A Headache
The B7 S4s V8 may be mighty, but it can be a diva to maintain. One of the most common issues with it regards the complex timing chain system it employs, which is known to eventually fail. The problem is usually caused by poor oil maintenance, and a failure will likely result in you needing to source a new engine. When inspecting a used S4, listen out for a ticking or rattling noise, or possibly a rough idle, upon cold starts. These are golden signs the timing chain is on its way out, so walk away if you hear them.
The V8 is also known to suffer from excessive oil consumption due to worn piston rings and oil cover gaskets, issues with the cooling system, as well as carbon build-up on the intake valves. Repair costs can quickly mount, so make sure to thoroughly inspect the engine and the car's maintenance history to ensure it's been well looked after before you hand over your cash.
The RS4 Makes More Sense For Gearheads Focused Purely On Pace
Should the S4s slightly softer base not sound appealing to you, and its more powerful sibling's higher used value doesn't pose much of an obstacle, then perhaps the Audi RS4 would be the best option. The RS4 underwent significant changes compared to the S4, which began with the engine. The 4.2-liter V8 from the S4 was used as a base, though its cylinder block was revised, a new intake manifold was developed, and a baffled oil sump to prevent oil starvation during heavy cornering was introduced. The compression ratio was also increased from 11.0:1 in the S4 to 12.5:1 with the RS4's shiny new V8.
It produced way more power as a result, with 420 hp being channeled to all four wheels via a six-speed manual gearbox. It could rev much higher than the V8 in the S4, with a redline of 8,000 rpm.
The RS4 was also afforded a wider body kit to allow Audi's engineers to widen its track, which gave the car extra stability when cornering and improved its center of gravity. A new hydraulic Dynamic Ride Control suspension setup was also developed, which worked to reduce the pitch and roll of the vehicle under hard driving to further improve handling. The brake system was also upgraded to deal with the extra grunt.
The RS4 didn't ride as well as the S4, but the extra tech ensured it was considerably more formidable when being treated like the angry performance car it is. All in all, just north of $20,000 is still pretty reasonable for a car with the reputation of the B7 RS4.
2026-07-06T05:39:40ZSources:Audi
