HP-19 vs.HP-24
02-04-2007, 11:23 AM
#11
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The S-Line may be able to handle more torque for a reason: improved TC that year
From a technical service bulletin I acquired when my (stock) '01 was throwing the dreaded 17125 code (note the discreet admission of a fault in the TC):
-------------------
TSB C 32-05-01 (and 02) dated 10/25/05
Models A6, Allroad w/2.7T (engine code APB, BEL, auto transmission), 2001-2004, to VIN 4B_4N024000
MIL ILLUMINATED, DTC 17125 stored in transmission fault memory
Condition: Malfunction Indicator Light [check engine] on, DTC 17125 "Torque converter clutch circuit performance or stuck off" stored in transmission fault memory
May be caused by torque converter internal oil seal failure
Service: Torque converter must be replaced. Internal torque converter seal is not replaceable.
... [transmission removal reference]
... [torque converter replacement reference]
Production: Vehicles after VIN 4B_4N024000 are fitted with an improved torque converter.
Only improved replacement parts are available from your Parts Depot.
---------------------------------
-------------------
TSB C 32-05-01 (and 02) dated 10/25/05
Models A6, Allroad w/2.7T (engine code APB, BEL, auto transmission), 2001-2004, to VIN 4B_4N024000
MIL ILLUMINATED, DTC 17125 stored in transmission fault memory
Condition: Malfunction Indicator Light [check engine] on, DTC 17125 "Torque converter clutch circuit performance or stuck off" stored in transmission fault memory
May be caused by torque converter internal oil seal failure
Service: Torque converter must be replaced. Internal torque converter seal is not replaceable.
... [transmission removal reference]
... [torque converter replacement reference]
Production: Vehicles after VIN 4B_4N024000 are fitted with an improved torque converter.
Only improved replacement parts are available from your Parts Depot.
---------------------------------
02-04-2007, 10:02 PM
#12
Bullsh!t
Three S4 people have toasted their 5HP19FLA trannies so far. All who are running on greater than Stage 2+ have moded the tranny.<ul><li><a href="https://forums.audiworld.com/s4/msgs/2560813.phtml">https://forums.audiworld.com/s4/msgs/2560813.phtml</a</li></ul>
02-05-2007, 06:36 AM
#15
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I was stg 2+ for over a year with no tranny probs. I've been stg 3- for 20K miles....
with just an L10 TC and NO problems. There are a lot on variables at play here - how was the tranny treated before you bought it? How do you treat it? Lots of hard 1st gear launches or occasionally get on it? How much power/torque do you plan to run through it?
There are plenty of stories posted about cars with lots of hp/tq that are doing fine with no/minimal tranny mods. There are also plenty of stories of cars with lots of hp/tq and no tranny mods that have "blown" their tranny. The guys that have invested the $5K in L10 tranny rebuilds seem to be the most vocal that you HAVE to get a rebuilt tranny. The guys that have torque converter and or valve body mods seem to be the most vocal about Not having to rebuild the tranny.
My thinking goes like this: if you're going with a mild (1 bar) chip and exhaust and drive reasonably, don't woryy about tranny mods. Most will agree that the tranny does fine under these conditions.
If you're going with K04s, consider at least an upgraded torque converter. The tranny must be removed to install this, so do it while the engine is out of the car. Also consider a valve body. This will increase line pressure, thus increasing clutch clamping force. A VB can be installed with the tranny in the car.
Re a complete "bulletproof" rebuild - If you're going to drive the car hard, do lots of hard launches, etc., consider it now. If you're going to drive the car less hard, wait. If the tranny breaks, fix it. If it doesn't, you saved $5k.
Finally, re the tranny swap to an HP24 - it has a completely different bellhousing for the larger TC. Therefore, its not going to fit the 2.7 w/o major work. If you're after a more durable 2.7 tranny, mod the HP19.
In summary, there's lots of anechdotal evidence on both sides of this argument, fewer facts (even this statement will be argued!). Talk to AWE, APR, Strat (O.CT), Jeff Moss, and others that have worked on LOTS of these applications. Search the forum, read the posts with a lot of critical thought (including this post), and make up you own mind.
Best of luck
There are plenty of stories posted about cars with lots of hp/tq that are doing fine with no/minimal tranny mods. There are also plenty of stories of cars with lots of hp/tq and no tranny mods that have "blown" their tranny. The guys that have invested the $5K in L10 tranny rebuilds seem to be the most vocal that you HAVE to get a rebuilt tranny. The guys that have torque converter and or valve body mods seem to be the most vocal about Not having to rebuild the tranny.
My thinking goes like this: if you're going with a mild (1 bar) chip and exhaust and drive reasonably, don't woryy about tranny mods. Most will agree that the tranny does fine under these conditions.
If you're going with K04s, consider at least an upgraded torque converter. The tranny must be removed to install this, so do it while the engine is out of the car. Also consider a valve body. This will increase line pressure, thus increasing clutch clamping force. A VB can be installed with the tranny in the car.
Re a complete "bulletproof" rebuild - If you're going to drive the car hard, do lots of hard launches, etc., consider it now. If you're going to drive the car less hard, wait. If the tranny breaks, fix it. If it doesn't, you saved $5k.
Finally, re the tranny swap to an HP24 - it has a completely different bellhousing for the larger TC. Therefore, its not going to fit the 2.7 w/o major work. If you're after a more durable 2.7 tranny, mod the HP19.
In summary, there's lots of anechdotal evidence on both sides of this argument, fewer facts (even this statement will be argued!). Talk to AWE, APR, Strat (O.CT), Jeff Moss, and others that have worked on LOTS of these applications. Search the forum, read the posts with a lot of critical thought (including this post), and make up you own mind.
Best of luck
02-05-2007, 08:29 PM
#17
Yes - I certainly can ...
say that any idiot advocating all 5HP19FLA transmissions can support more than ZF specs it for, for some reasonable amount time, has the burden of proof. Not me.
And anyone recommending to readers that they'll be fine pumping 400+ ft.lbs into a stock components rated for 220 ft.lbs - in the face of documented failures - is being deceptive and grossly irresponsible.<ul><li><a href="http://www.zf.com/ZF_ProductDB/user/applicationLayerContentPage?pageID=316706&prod uctTypeID=316700&versionID=321872&applicat ionID=12288&applicationGroupID=&businessUn itShortcut=&divisionShortcut=&languageI
And anyone recommending to readers that they'll be fine pumping 400+ ft.lbs into a stock components rated for 220 ft.lbs - in the face of documented failures - is being deceptive and grossly irresponsible.<ul><li><a href="http://www.zf.com/ZF_ProductDB/user/applicationLayerContentPage?pageID=316706&prod uctTypeID=316700&versionID=321872&applicat ionID=12288&applicationGroupID=&businessUn itShortcut=&divisionShortcut=&languageI
02-06-2007, 06:23 AM
#18
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I am not dis-agreeing with you on the specs., but I have been talking to a bunch of
the B5S4 guys doing research since I am also going stage 3 with a tip. No one really knows why they fail.
Mostly we can all agree on the TC seal which has been known to also be problematic on stock cars.
Sure adding extra torque and horsepower to a transmission can shorten it's life, by how much no one knows.
Instead of 300,000 miles maybe only 100,000 no one REALLY knows that is what I am trying to say.
Certainly if you look at the transmission in the RS6 it is also rated BELOW the input torque of the motor, and RS6 people modify their cars as well exceeding the limits.
But even the guys with stock cars have problems with them just like the A6 people with the 4.2
So if one of them have transmission problems is it because the car was modified, or just because??
No one really knows...
Mostly we can all agree on the TC seal which has been known to also be problematic on stock cars.
Sure adding extra torque and horsepower to a transmission can shorten it's life, by how much no one knows.
Instead of 300,000 miles maybe only 100,000 no one REALLY knows that is what I am trying to say.
Certainly if you look at the transmission in the RS6 it is also rated BELOW the input torque of the motor, and RS6 people modify their cars as well exceeding the limits.
But even the guys with stock cars have problems with them just like the A6 people with the 4.2
So if one of them have transmission problems is it because the car was modified, or just because??
No one really knows...
02-06-2007, 07:37 PM
#19
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Re: RS6 uses a 5HP24A with the hgiher torque TC - you might be able to retrofit...
Yes, of course you are right...it's a shame that Audi did not offer the higher torque TC as an option with the 2.7T.