A6 Durability
Thread Starter
Intermediate
Joined: May 2002
Posts: 36
Likes: 0
From: Bowling Green KY
A6 Durability
Does anyone have a guess as to how much torque the A6 can stand up to? I was considering getting one in my 2006 which I plan to have supercharged. I drive a lot in town, and really don't want to have to deal with a MN6. I wonder if the power loss from the crank to the wheels will be greater than or less than the standard A4. Any thoughts, ideas, or input? I hope it is comparable to the ones used in the Mercedes AMG cars. Does anyone remember the comparison between the C6, and the SLK 55 AMG with the A7? I'm thinking the A6 performance should fall between the A4, and MN6. Please correct me if I am mistaken. Thanks.
Le Mans Master
Joined: Oct 2004
Posts: 6,813
Likes: 287
From: Toronto Ontario Canada
I think you should step back and think about this. The new A6 transmission has no proven durability - it is new. GM may introduce running changes during the first year to correct any problems that surface. It is hoped this would be minimal. However to take a new transmission like this and subject it to loads that it was not designed to handle is crazy. If you can afford to do this and void your warranty go ahead but I don't think this is very wise.
Burning Brakes
Joined: May 2004
Posts: 996
Likes: 13
From: Dallas TX
I haven't kept up with the specs on the A6, but if it is using the 6L80 that Caddies will be using then it should have some wiggle room for improvement as the SC'd Caddies put out more HP & torque than a C6 (torque & HP around 440?)
Thread Starter
Intermediate
Joined: May 2002
Posts: 36
Likes: 0
From: Bowling Green KY
Thank you all for the voices of reason. Really to be safe I’d have to have the auto built up to handle the power. I guess I need to decide if I truly want to do this, because doing so will require a MN6. I mean 550+ HP and the monster torque would liquefy the stock auto trans. Thanks again.
Instructor
Joined: Sep 2004
Posts: 229
Likes: 0
I read in an earlier post that there is more than one model number for the rwd A6 tranmission. The one initially to be used in the C6 is good for 430 ft lb rating. Another model is rated at something like 520 ft lbs. I don't know if it is larger or heavier or what. However, it could well be an upgrade as the Vette evolves. I mean, the Vette is knocking on the door of the top rating as it is, and we all know (well, speculate anyway 
) that 3 valve heads, direct gas injection, etc. will boost power significantly in future years.
BTW, the old 700XXX automatic in the Buick GN turbo cars wasNEVER rated anywhere near the power that many of them made. Tranny upgrades were necessary for the overachiever tuners, but they put up with more abuse than you could have predicted.
) that 3 valve heads, direct gas injection, etc. will boost power significantly in future years.BTW, the old 700XXX automatic in the Buick GN turbo cars wasNEVER rated anywhere near the power that many of them made. Tranny upgrades were necessary for the overachiever tuners, but they put up with more abuse than you could have predicted.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Le Mans Master
Joined: Sep 2004
Posts: 7,027
Likes: 6
From: Shiloh Ohio
Originally Posted by Mobile Man
I read in an earlier post that there is more than one model number for the rwd A6 tranmission. The one initially to be used in the C6 is good for 430 ft lb rating. Another model is rated at something like 520 ft lbs. I don't know if it is larger or heavier or what. However, it could well be an upgrade as the Vette evolves. I mean, the Vette is knocking on the door of the top rating as it is, and we all know (well, speculate anyway ) that 3 valve heads, direct gas injection, etc. will boost power significantly in future years.
BTW, the old 700XXX automatic in the Buick GN turbo cars wasNEVER rated anywhere near the power that many of them made. Tranny upgrades were necessary for the overachiever tuners, but they put up with more abuse than you could have predicted.
) that 3 valve heads, direct gas injection, etc. will boost power significantly in future years.BTW, the old 700XXX automatic in the Buick GN turbo cars wasNEVER rated anywhere near the power that many of them made. Tranny upgrades were necessary for the overachiever tuners, but they put up with more abuse than you could have predicted.
Race Director
Joined: Oct 2004
Posts: 10,089
Likes: 14
Originally Posted by shurite44
The heavier tranny is called the X16R variant D. I do not know what the tranny designator will be when GM uses it, this is the testing number. It is also a six speed and it rated at 520 ft lbs. I have seen opinions it is going to be used on the C6 Z06. Just rumors as far as I know but it does make some sense.
Le Mans Master
Joined: Sep 2004
Posts: 7,027
Likes: 6
From: Shiloh Ohio
Originally Posted by shopdog
A Z with an auto? Doubt it. But that heavier tranny will certainly find a home in the Silverado. That's good news, it means they're going to make tons of them, so parts, including aftermarket speed parts like high stall converters, should be cheap.
Race Director
Joined: Oct 2004
Posts: 10,089
Likes: 14
Originally Posted by b4i4getit
I think you should step back and think about this. The new A6 transmission has no proven durability - it is new. GM may introduce running changes during the first year to correct any problems that surface. It is hoped this would be minimal. However to take a new transmission like this and subject it to loads that it was not designed to handle is crazy. If you can afford to do this and void your warranty go ahead but I don't think this is very wise.
Second, the 2006 A6 comes with a 2.56 rear. The 2.xx carrier is smaller and weaker than the 3.xx carrier. A tall 2.56 rear also means not much torque multiplication in the rear, so the torque at the differential input (tranny output) has to be higher to give the same rear wheel torque. That means the pinion sees much higher stress, the tranny output shaft sees much higher stress, etc, and there are no heavier duty parts from the aftermarket to address these issues.
So, if you want a high output car with FI, or just a NA screamer, the A6 isn't ready for prime time, and won't be until these weaknesses are addressed by the aftermarket. There are solutions for the venerable A4, and of course for the MN6 cars. So if you plan to make a lot of power and torque in the next couple of years, you really want to avoid the new A6. But if you can wait to mod until the aftermarket has time to come out with fixes for the A6, then it may be a good choice.
Thread Starter
Intermediate
Joined: May 2002
Posts: 36
Likes: 0
From: Bowling Green KY
Again, more good points. Thank you. I'm actually thinking about the Z again, just because its ready to go when you buy it. I hate to have anyone start hacking on a brand new car. I just don't have good luck with such things. I'll wait and see.
Drifting
Joined: Jun 2001
Posts: 1,270
Likes: 0
From: Prescott AZ
Originally Posted by Black04Vert
I haven't kept up with the specs on the A6, but if it is using the 6L80 that Caddies will be using then it should have some wiggle room for improvement as the SC'd Caddies put out more HP & torque than a C6 (torque & HP around 440?)
Pro
Joined: Sep 2004
Posts: 678
Likes: 0
From: Winchester VA
Originally Posted by Tom73
My thought on the C6 was to wait a year for the bugs to get out before buying one. Now a new transmission. Best give that two years to work the kinks out. So maybe an '08
Team Owner
Joined: Feb 2001
Posts: 27,253
Likes: 134
From: Short Hills, NJ
Originally Posted by C64BC
Oh i'm sure they'll add something new over the next year or so...so you better wait 'til 2010 to make sure all the bugs are worked out before you get one.
