What's the difference?

OK, I'm an Audi noob. Let's get that straight before we begin. I have a friend who drove a '93 S4 until he rearended somebody. Now he's buying an S6, which looks the same as the S4 and has only a slightly different drivetrain. I don't remember what year the S6 is. I went to Audi's website to try to figure out the difference between the various Audis, but they're no help. It's like trying to figure out the difference between the types of Porsches or Mercedes. Porsches just use the same sets of three digits over and over again in different combinations and occasionally throw in the word "Carrerra" or "Turbo" or "S". I've come to terms with that. Mercedes mixes and matches its labels, too. I've come to terms with the fact that I'll never figure their labeling system out, either. All I have to remember is that the bigger the number, the bigger the engine and that "AMG" is relatively equivalent to "///M".

Now, modern BMWs are easy. The first digit is the class of the car (generally speaking), and the second two digits are the size of the engine. The "i" means fuel injected (which is kind of superfluous now). Thus a 325 is a compact (3) with a 2.5L engine (25). A 325xi has all-wheel drive. An "L" has the long wheelbase, and so on.

So... how do you tell the difference between different Audis? The A4, A6, etc. all look the same to me, all come with different trim levels, are all made in seemingly random years. What's the RSwhatever? I got the TT's down, since they're the only ones that are not rectangular. Audiworld.com has not been particularly helpful on this issue, either. Over the years, it moved from S6 to "S6 series." So, help me out here. What's the difference between the S3, 4, 6, 8, A3, 4, 6, 8, RS4, 6, and Allroads? They really do look the same to me. Pictures would be helpful.

Now that's a big question. As for your friend's S6 and S4, those are the older models which really were very similar. They had almost the same body, but the S6 was slightly longer and bigger. Maybe somebody else on here can chime in with more differences than that.

As for the more current models (let's say 1998 until present) there have basically been two different A4/S4 body styles, two A6 body styles, two A8 body styles, and one All-road (which is based on the A6 platform). Below are some pics to help explain it better.

Starting in with the 97-2001 A4's 1.8L I-4 Turbo engine or 2.8L V6 engine (There were minor differences between some of these; things like windshield washers moved, 1 vs 2 piece headlights, etc. But the basic body is the same) It's also known as the B5 chassis A4.
http://img35.exs.cx/img35/7412/AudiSide1med.jpg

Here's the S4 from 2000-2001 (It's based on the same body as the previous A4 with slight modifications and a 2.7Liter Twin-turbocharged V6)
http://img99.exs.cx/img99/2097/S4front.jpg

Here's the newer model of A4. It came with the nearly the same 1.8T engine plus a 3.0L (2002 to present) Also known as the B6 chassis A4
http://img99.exs.cx/img99/4115/A4_2002.jpg

And the S4 from the same years has a very similar body but with a 4.2L V8. Here's a pic...
http://img99.exs.cx/img99/6454/Audi-s4.jpg

Now onto the other models...

As for the A6 (that's Audis midsize sedan here in the US), the old style of A6 looks a lot like the newer A4's (see above). But if you see them in person, the A6 is noticeably bigger.

The first body style was offered with a 1.8T, 2.8L V6 or a 4.2L V8. Here are some pics of that one (1997-2002 IIRC)
http://img99.exs.cx/img99/7587/A6_1999.jpg

They did not make an S6 in these years that was sold in the US. They did however make an RS6 which had nearly the same body with side skirts, and a more aggressive stance. It had a 4.2L twin-turbocharged V8 and was offered in 2000-2002 IIRC.
http://img99.exs.cx/img99/2600/sportec_rs6_avant_1.jpg

Now there is a new body style of A6, here's what it looks like...
http://img99.exs.cx/img99/8505/2005A6.jpg

Now on to the A8's...

The the "8-series" has had basically two body styles from 1998 to present also. Here's some pics of the 1997 - 2003 body. Once again, it may look similar to the others in pics, but it is much bigger when you see it in person.
http://img99.exs.cx/img99/1865/A8_1999.jpg

they also offered a "Long" version designated with a "L" it was known as the A8 L.

The new body style of the A8 looks like this...

http://img99.exs.cx/img99/7834/2004_A8.jpg

And lastly, the all-road is based on the A6 platform but it's a little higher off the ground. Here's a pic...

http://img99.exs.cx/img99/8387/audiallroad-28s.jpg

Now for the cars that Audi hasn't offered in the US yet...

The cars that you may have heard of that Audi hasn't offered in the US yet are the S8, A/S3, RS4, and the A2.

Here's the S3 (based on the VW golf platform), the A3 is very similar but less aggressive.
http://img27.exs.cx/img27/5426/audi_s3.jpg

the RS4 is based on the A4 platform but is wider, longer, and has a "tweaked" 2.7L twin turbo V6.

http://img27.exs.cx/img27/6699/Audi20RS4-002.jpg

The S8 is basically the same as the A8, but with a much more powerful engine and tuned suspension.

The A2 is a commuter car here's a pic...
http://img27.exs.cx/img27/2066/audia2-05s.jpg

I think that's about it, there could be more small differences that I am forgetting though. That's the jist though. So, the numbers go like this... The bigger the number, the bigger the car, the "A" or "S" or "RS" in front of the number designates if it's the "A"udi, "S"ports, or "R"acing "S"ports version of the model. And there are different engines offered for each model. The engine that's in the car is badged on the back of US-spec cars. In other countries, it is left off sometimes. Hope that answered your question.

Excellent answer! Thank you! My only remaining question is, Why does the RS only come in wagon format? No disrespect to the wagon (I do drive a sport wagon, after all), but it seems like a lot of people would want a sedan version rather than a wagon.

Wow. Really, thanks. I was half-expecting some crazy, unintelligible answer, but that was laid out all logically and even had a summary at the end to bring it all together. Awesome. You should be running for president instead of the four or five bozos that currently are. :-)

Edit: And why "RS" instead of just "S"?

LOL, thanks! I don't know about me running for pres, but somebody other than who we've got WOULD be nice!!

As for the "wagon" question, I don't really know why they chose the wagon. I do know that the RS6 comes in sedan form though too. The RS4 is only available in wagon though. I think they might have just done it to be different.

Does anybody else have a better answer than that? I would like to know too!

AFAIK, the RS stands for Racing Sport whereas the S just stands for Sport. It's just a way to designate the car as being even more powerful and tuned than the "S"

I do believe the S8 came to America...

Ur right, I didn't know that before. Thanks for the correction.


Man! Now I want one!! :D