A6 transmission flush
Thread Starter
Pro
Joined: Jul 2013
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A6 transmission flush
Hey all,
I need to have my transmission cooler lines re-routed (the cooler in the radiator was bypassed when my auxiliary cooler was installed and I need to have it re-connected). My tuner recommended that I have a transmission fluid flush performed at the same time to clean out the system.
I know some believe that this is a bad idea, and some swear by it. I'm doing it because my fluid's been way too hot a couple times and also because the coolers are definitely going to need to be cleaned out after being disconnected for 6 months. If you really think this is a bad idea, I'd really like to know why before I bring it in and potentially blow something up.
Has anyone done this, and if so what do I need to look for in the shop that does the job? Am I better off going to the dealership or finding a local shop? The only shop around here that does it is some 10-minute oil change place and that's not very confidence inspiring.....haven't talked to the dealer about it yet but I'm hesitant to bring a modified car to a dealer for service.
I need to have my transmission cooler lines re-routed (the cooler in the radiator was bypassed when my auxiliary cooler was installed and I need to have it re-connected). My tuner recommended that I have a transmission fluid flush performed at the same time to clean out the system.
I know some believe that this is a bad idea, and some swear by it. I'm doing it because my fluid's been way too hot a couple times and also because the coolers are definitely going to need to be cleaned out after being disconnected for 6 months. If you really think this is a bad idea, I'd really like to know why before I bring it in and potentially blow something up.
Has anyone done this, and if so what do I need to look for in the shop that does the job? Am I better off going to the dealership or finding a local shop? The only shop around here that does it is some 10-minute oil change place and that's not very confidence inspiring.....haven't talked to the dealer about it yet but I'm hesitant to bring a modified car to a dealer for service.
Team Owner
Joined: Sep 2005
Posts: 20,352
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From: Ventura County, Calif
Obviously just my opinion but I think many of us recommend against trans flushing for no good reason, like "it has 50k miles on it", or "I like to do preventative fluid changes", etc. If the fluid looks good, doesn't smell burned and the trans is working correctly then there is no reason to do a flush. There have been too many stories here of problems after flushing.
That is certainly not your case and a flush in conjunction with your other work, and considering the prior heating issue, is appropriate, again in my opinion.
Sounds like the dealer is going to be your best bet. I wouldn't trust a quick lube type place. Talk to the service manager and get the best assurances you can that they know what they're doing and have the latest equipment. If you aren't convinced then keep looking.
That is certainly not your case and a flush in conjunction with your other work, and considering the prior heating issue, is appropriate, again in my opinion.
Sounds like the dealer is going to be your best bet. I wouldn't trust a quick lube type place. Talk to the service manager and get the best assurances you can that they know what they're doing and have the latest equipment. If you aren't convinced then keep looking.
Thread Starter
Pro
Joined: Jul 2013
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I found another shop in the area that will do a flush; I will go by this afternoon and discuss the process in detail. I want to see which type of machine they have and how much experience they have using it. If I'm not satisfied, I'll be sitting down with a service advisor at the dealer later.
Thread Starter
Pro
Joined: Jul 2013
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Just under 20,000 (twenty thousand) miles. The fluid was changed once when the auxiliary cooler was added, but it was not flushed to my knowledge. That would've been somewhere around 10-12k miles ago. Both sets of fluid have seen 240+ temps (Fahrenheit) on track and 200+ driving in town regularly.
Race Director
Joined: Sep 2007
Posts: 16,557
Likes: 2,108
From: Peoria/Phoenix AZ
C6 of Year Finalist (performance mods) 2019
Personally, I'd never do a flush. Dropping the pan to clean it and change the filter will require about 6.5 quarts of fluid. In your case, you might want to pump a little fluid in the cooler while it's not connected to anything else and then blow it out to get rid of any dirt accumulation. Look at the fluid coming out for dirt and repeat if necessary.
Then after you drive it a couple hundred miles, siphon out as much as possible (probably 6-7 quarts) and refill with fresh fluid. You'll end up with 75-80% new fluid and a fairly clean filter.
I don't know where you are, but I'd avoid a dealer, even if I had to drive hundreds of miles to find someone knowledgeable.
Learning how to do it and then doing it yourself is the best way to know it got done right. The bonus is not only the cost, but the self-satisfaction.
BTW, the 200 degrees in town is not a big deal, but continuous running at 240+ is a problem.
Then after you drive it a couple hundred miles, siphon out as much as possible (probably 6-7 quarts) and refill with fresh fluid. You'll end up with 75-80% new fluid and a fairly clean filter.
I don't know where you are, but I'd avoid a dealer, even if I had to drive hundreds of miles to find someone knowledgeable.
Learning how to do it and then doing it yourself is the best way to know it got done right. The bonus is not only the cost, but the self-satisfaction.
BTW, the 200 degrees in town is not a big deal, but continuous running at 240+ is a problem.
Last edited by HOXXOH; Sep 22, 2014 at 03:09 PM.
Race Director
Joined: Oct 2010
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From: Las Vegas NV
I had my A4 flushed at the dealer about 1000 miles ago for under $200. It was at 50K miles. I expressed my concern to the SA about horror stories I've heard about and he swore it would be ok. Well it has been. No problems at all.
Thread Starter
Pro
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Well, really doesn't matter anymore because today I discovered that no one will touch my car because it isn't 100% stock anymore. Meineke told me to go to the dealer to make sure that I don't have any kind of real issue with the trans, and the dealer won't even look at the thing because they "don't mess with anything that's modified".
So at this point I'm scheduled to bring it in to the shop that initially installed the cooler and they're gonna re-run the lines, drop the pan, and run a few sets of fresh fluid through the system. The lines on the radiator are capped off so there shouldn't be any debris in there. They don't have a flush machine, and honestly from what I've read it probably isn't necessary to flush it anyway.
I would absolutely love to do this myself but as it's more complicated than turning a wrench I don't feel like having my only vehicle on jack stands for more than an hour or four.
So at this point I'm scheduled to bring it in to the shop that initially installed the cooler and they're gonna re-run the lines, drop the pan, and run a few sets of fresh fluid through the system. The lines on the radiator are capped off so there shouldn't be any debris in there. They don't have a flush machine, and honestly from what I've read it probably isn't necessary to flush it anyway.
I would absolutely love to do this myself but as it's more complicated than turning a wrench I don't feel like having my only vehicle on jack stands for more than an hour or four.
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Tech Contributor
Joined: Oct 2008
Posts: 1,378
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From: St Louis MO
Here's a thread you might want to review.
It's really not very hard and any decent mechanic should be able to do it if they can follow instructions. What looks like a drain plug is actually how you set the fluid level with the car level and the motor running.
It's really not very hard and any decent mechanic should be able to do it if they can follow instructions. What looks like a drain plug is actually how you set the fluid level with the car level and the motor running.
Pro
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From: McMinnville TN
Stacey
Melting Slicks
Joined: Jul 2010
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From: Surprise, Az
240 shouldn't be much of a problem. The transmission will go into cool down mode about 280 I think. I had mine to 240 a few times before upgrading my radiator, had the dealer install the aftermarket radiator and flush the transmission and change its filter. The mechanic told me the transmission fluid looked like new. The car ran great for the remainder of the hpde season last year and all of this year.