Results 1 to 9 of 9

Thread: Main Radiator Differences.

  1. #1
    Registered User Blau_RS2's Avatar
    Join Date
    Feb 2018
    Location
    Calgary, AB
    Posts
    31

    Main Radiator Differences.

    Anybody know what the differences are between the early RS6 main radiator and the later one's? There doesn't seem to be any aftermarket options for the later one. Part number is 4B3121251F versus a D for the earlier one.

    There seems to be an extra inlet for the transmission fluid possibly? Wonder if there is a way to bypass this and use an earlier Rad as the price difference is significant. ~$1100 vs $300.
    2004 RS6 Avant
    1994 RS2 Avant
    2008 S4 Avant

  2. #2
    Registered User hahnmgh63's Avatar
    Join Date
    Feb 2007
    Location
    Roy, WA
    Posts
    3,303
    Not sure what the difference is but I think the 'D' version is for the A6 4.2 and the 'F' version is for the RS6. I was looking to buy a spare a while back and that is what I remember in a search. Since going Manual, I might look into the dimension of the A6 Manual radiator since I don't need the tranny cooling anymore.
    2003 White RS6 2013 Midnight Blue S5
    2013 Daytona RS5 2x944 Turbo's 1974 911 w/'91 3.6ltr motor
    Roy, WA

  3. #3
    Registered User
    Join Date
    Mar 2007
    Location
    Evil Empire
    Posts
    466
    Quote Originally Posted by hahnmgh63 View Post
    Not sure what the difference is but I think the 'D' version is for the A6 4.2
    This is correct.
    Early RS6 is 4B3121251E.

  4. #4
    Registered User Blau_RS2's Avatar
    Join Date
    Feb 2018
    Location
    Calgary, AB
    Posts
    31
    So I assume the eBay ads showing that the D version works on the RS6 are just incorrect. Does anyone know if there is an alternative to the Audi radiator for the RS6?
    2004 RS6 Avant
    1994 RS2 Avant
    2008 S4 Avant

  5. #5
    Registered User
    Join Date
    Mar 2007
    Location
    Evil Empire
    Posts
    466
    Quote Originally Posted by Blau_RS2 View Post
    Does anyone know if there is an alternative to the Audi radiator for the RS6?
    None that I'm aware of.

    Anyway, did a bit of googling. Early RS6 rad. S6/A6 4.2 rad. They look pretty damn similar to me.
    BUT!
    1) Even if physical dimensions and fittings are 100% the same (and condenser mounting tabs, etc), they still might have different cores & different cooling capacity.
    2) Late RS6 rad is different in that it has an extra fitting for aftercooling pump. You can get away with just plugging that, but potentially it can cook your turbos eventually.
    Aftercooling systems are pretty different between early/late RS6 - they have different directions of (after)coolant flow (and late models have an extra electromagnetic valve).

    Is your rad FUBAR? Or, if it's repairable, might be a best idea to just go that way.
    Last edited by nubcake; January 30th, 2019 at 01:27. Reason: typo

  6. #6
    Registered User hahnmgh63's Avatar
    Join Date
    Feb 2007
    Location
    Roy, WA
    Posts
    3,303
    They look close, would be nice to find a big part supplier or dealer that stocked both or at least get the 'D' version and see what it looks like side by side.
    2003 White RS6 2013 Midnight Blue S5
    2013 Daytona RS5 2x944 Turbo's 1974 911 w/'91 3.6ltr motor
    Roy, WA

  7. #7
    Registered User Blau_RS2's Avatar
    Join Date
    Feb 2018
    Location
    Calgary, AB
    Posts
    31
    Quote Originally Posted by nubcake View Post
    Is your rad FUBAR? Or, if it's repairable, might be a best idea to just go that way.
    I'm waiting to hear from my mechanic to see if it's repairable or not. I'm hoping it can be fixed but I was just looking for other options. I haven't even seen the car yet and I'm already dealing with issues!
    2004 RS6 Avant
    1994 RS2 Avant
    2008 S4 Avant

  8. #8
    Registered User
    Join Date
    May 2015
    Location
    West Linn, OR
    Posts
    291
    Supposedly this shop has built a custom radiator for the RS6:

    https://wizardcooling.com/

    You might ping them and see what they say. If they do, please post an update. I'm curious, but too lazy to do the work myself

  9. #9
    Registered User Blau_RS2's Avatar
    Join Date
    Feb 2018
    Location
    Calgary, AB
    Posts
    31
    Quote Originally Posted by GreggPDX View Post
    Supposedly this shop has built a custom radiator for the RS6:

    https://wizardcooling.com/

    You might ping them and see what they say. If they do, please post an update. I'm curious, but too lazy to do the work myself
    Here's an update to my search for a new radiator. I ended up going with a new Audi one from the dealer. I talked to Wizard Cooling and they said they'd be able to make a custom one but they wouldn't be able to do it with the OEM fittings and I'd have to customize the lines going into the radiator. Their radiator would have been about $1000 plus the custom lines. In the end not really a savings over the OEM Rad. I don't plan on going much more than a Stage 1 and I'm up in Canada so extra cooling wasn't really a priority.
    2004 RS6 Avant
    1994 RS2 Avant
    2008 S4 Avant

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •