? '08 A6 differential cooler?
Thread Starter
Race Director
Joined: Mar 2005
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From: Austin Texas
? '08 A6 differential cooler?
I would like to find out if there are any '08 Z51 A6 Coupes or Converts that actually have a factory differential cooler. The '08 Service Manual shows one but I have an '08 Z51 A6 and it does NOT have a differential cooler.
The question is: Does anyone with an '08 Z51 A6 have a Factory Differential Cooler? Easy to check, just look between your mufflers at the rear cover of the Diff., if it's plain you do not have a Diff. cooler, if the cover has hose and fittings you do have a diff. cooler.
The service Manual shows the cooler as available on the 2.73 axle ratio and since there were 8,839 A6's with the 2.73 ratio there should be someone on this Forum that has one (if they were actually available).
Please check your car ('08 Z51 A6) and see if it has a differential cooler and post in this thread yes or no. Thanks.
The question is: Does anyone with an '08 Z51 A6 have a Factory Differential Cooler? Easy to check, just look between your mufflers at the rear cover of the Diff., if it's plain you do not have a Diff. cooler, if the cover has hose and fittings you do have a diff. cooler.
The service Manual shows the cooler as available on the 2.73 axle ratio and since there were 8,839 A6's with the 2.73 ratio there should be someone on this Forum that has one (if they were actually available).
Please check your car ('08 Z51 A6) and see if it has a differential cooler and post in this thread yes or no. Thanks.
Melting Slicks
Joined: Jun 2009
Posts: 3,142
Likes: 1
From: SE Coast FL
I was at the dealer yesterday looking for the lines to attach a cooler to my new Z06 diff and to the existing tranny cooler lines. It looks like it can be done for about $3-400 in oem lines (Z diff already has a pump). Domestic A6 vettes did not come with it RPO/KNP, exported did RPO/KNR.
Thread Starter
Race Director
Joined: Mar 2005
Posts: 10,399
Likes: 25
From: Austin Texas
I was at the dealer yesterday looking for the lines to attach a cooler to my new Z06 diff and to the existing tranny cooler lines. It looks like it can be done for about $3-400 in oem lines (Z diff already has a pump). Domestic A6 vettes did not come with it RPO/KNP, exported did RPO/KNR.
Export only? Wish the Factory Manual would say so.
Team Owner
Joined: Sep 2000
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From: Far NW 'burbs of Chicago
St. Jude Donor '13
Not to hijack the thread, but differential cooling may not be the biggest problem with an A6. In that ~45 minute video made at Sebring, Tadge Juechter (sp?) was asked why the A6 GS does not come with the dry sump engine. His answer was that the A6 was not engineered to take high lateral G loadings, and the limiting factor in the car is the A6, not the engine oil system. He made some comment about getting an overheat warning.
It all suggests that even with an extra tranny cooler, the A6 may not stand up to the frequent or sustained lateral G you get on a road course; the differential would not be the first thing to fail.
Or maybe you have a different application in mind.
I've got more questions, than answers...
It all suggests that even with an extra tranny cooler, the A6 may not stand up to the frequent or sustained lateral G you get on a road course; the differential would not be the first thing to fail.
Or maybe you have a different application in mind.
I've got more questions, than answers...
Race Director
Joined: Sep 2007
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
However, there is mention of RPO/KNR vs. W/O RPO/KNR to R&R the left side carrier cover for seal replacement.The RPO description for KNR is "Cooling System - Axle".
The RPO for KNP is "Cooling System - Trans, HD"
The RPOs that deal with exports specify that they are export and usually indicate the country or area.
With the 2.73 gear as a $300 option on non-Z51 optioned cars, it makes me wonder if those had the differential cooler.
There's a lot of pages and illustrations for A6 coolers and non-Z06 M6 coolers to only have a use for export explanation.
It sure poses more questions to be answered.
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Race Director
Joined: Sep 2007
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From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
The pump on the rear cover is standard on a Z06 to pump fluid through the cooler, but the service manual indicates and illustrates the same pump and cooler for A6 and non-Z06 manual cars.
The purpose of this thread is to find those non-Z06 cars with pumps/coolers to understand how they came to be.
The purpose of this thread is to find those non-Z06 cars with pumps/coolers to understand how they came to be.
Thread Starter
Race Director
Joined: Mar 2005
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From: Austin Texas
I didn't think the Z06 differential would bolt to an A6 transmission. Input/output shaft diameter and spline count is supposed to be different between the A6 and Z06 transmissions.
Melting Slicks
Joined: Jun 2009
Posts: 3,142
Likes: 1
From: SE Coast FL
06+ all vettes are 30 spline I have been told, as well, countless posts state the Z diff will mount up as a direct bolt on and no one has challenged that. the only adjustment is the tranny mounts where you can buy Pfadts or drill the existing hole to give the oem mount some play to align it.
Melting Slicks
Joined: Jul 2007
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From: Brentwood World's first A6 in the 9's (including N/A, blower, turbo and nitrous cars) 9.950@139.267 CA
For whatever reason, the Z06 differential will only bolt up to either the Z06 trans or the A6 but not a regular C6 manual transmission.
Melting Slicks
Joined: Jun 2009
Posts: 3,142
Likes: 1
From: SE Coast FL
Melting Slicks
Joined: Jun 2009
Posts: 3,142
Likes: 1
From: SE Coast FL
)
Melting Slicks
Joined: Jun 2009
Posts: 3,142
Likes: 1
From: SE Coast FL