Trans fluid flush
Thread Starter
Instructor
Joined: Jun 2009
Posts: 175
Likes: 0
From: North Texas
Trans fluid flush
Hey everybody!! I want to change the fluids in the trans, and I am curious....should I simply drain the old and put in some new, or take it somewhere and have it flushed out and changed? I used to have my Z28 fluids flushed, but I don't want to take the vette to any shop and have something like that done without prior knowledge of who will be working on it... thoughts?
Race Director
Joined: Jan 2007
Posts: 16,513
Likes: 4
From: Official Dirty Dozen Member
some go crazy saying flushing causes problems
they are wrong
go ahead and do it
some of the commom bs you will hear ....
it loosens particles , well bs because the "flush" is just 2 tanks , one for filling , one for emptying , the pressure is the same as line pressure ...why ? ...the motor is running and the transmission moves all the fluid
OR
I did it and my trans broke....may have , why ? poor maint.
they are wrong
go ahead and do it
some of the commom bs you will hear ....
it loosens particles , well bs because the "flush" is just 2 tanks , one for filling , one for emptying , the pressure is the same as line pressure ...why ? ...the motor is running and the transmission moves all the fluid
OR
I did it and my trans broke....may have , why ? poor maint.
Last edited by thetaxman; Oct 12, 2009 at 09:44 AM.
Thread Starter
Instructor
Joined: Jun 2009
Posts: 175
Likes: 0
From: North Texas
Thanks for your input TaxMan!! I knew there were going to be 2 sides to this topic....So how many miles were on yours when you changed it yourself and how long did it last after you did it before the trans crapped out?
Instructor
Joined: Aug 2009
Posts: 226
Likes: 2
yeah, im on the other side. i say the taxman is dead *** wrong. ive seen flushing cause problems time and time and time again. then gain i cut my teeth on older vehicles with more issues.. but even still.
im assuming you are auto. depends on if you are having any issues. if your car is running fine with no issues and the exisiting fluid still is reddish, simply draining the pan, and replacing the fluid is more than enough to keep up with your maintenance schedule. if you really want you can change the filter while your at it.. and be done with it.
if you want to try and flush it yourself, and dont read over the procedure carefully, you can royally F. SH. up. for that matter, whomever you'd pay to flush it probably cant do it right either.
im assuming you are auto. depends on if you are having any issues. if your car is running fine with no issues and the exisiting fluid still is reddish, simply draining the pan, and replacing the fluid is more than enough to keep up with your maintenance schedule. if you really want you can change the filter while your at it.. and be done with it.
if you want to try and flush it yourself, and dont read over the procedure carefully, you can royally F. SH. up. for that matter, whomever you'd pay to flush it probably cant do it right either.
Race Director
Joined: Jan 2007
Posts: 16,513
Likes: 4
From: Official Dirty Dozen Member
yeah, im on the other side. i say the taxman is dead *** wrong. ive seen flushing cause problems time and time and time again. then gain i cut my teeth on older vehicles with more issues.. but even still.
im assuming you are auto. depends on if you are having any issues. if your car is running fine with no issues and the exisiting fluid still is reddish, simply draining the pan, and replacing the fluid is more than enough to keep up with your maintenance schedule. if you really want you can change the filter while your at it.. and be done with it.
if you want to try and flush it yourself, and dont read over the procedure carefully, you can royally F. SH. up. for that matter, whomever you'd pay to flush it probably cant do it right either.
im assuming you are auto. depends on if you are having any issues. if your car is running fine with no issues and the exisiting fluid still is reddish, simply draining the pan, and replacing the fluid is more than enough to keep up with your maintenance schedule. if you really want you can change the filter while your at it.. and be done with it.
if you want to try and flush it yourself, and dont read over the procedure carefully, you can royally F. SH. up. for that matter, whomever you'd pay to flush it probably cant do it right either.
this is?
do a mouse over on my original post
I told the OP this would happen
Instructor
Joined: Aug 2009
Posts: 226
Likes: 2
i feel you are wrong. sorry. i am a mechanic. i hear the wives tales every single day. i hear the conjecture and the arguments. somethings could go either way this being one of them.. but, as i said, its an unnecessary risk. will his transmission run an extra 500 miles if he does it your way? probably not. so why risk it?
Melting Slicks
Joined: Dec 2003
Posts: 2,857
Likes: 2
From: pawleys island sc
i am a mechanic. i hear the wives tales every single day. i hear the conjecture and the arguments. somethings could go either way this being one of them.. but, as i said, its an unnecessary risk. will his transmission run an extra 500 miles if he does it your way? probably not. so why risk it?
Of course you're correct in saying that if you bring your car to some A-hole who thinks he's a qualified, up to date mechanic and in truth is not, it is likely that he'll cuase you problems - but that's also true even if he just adds oil to your car or gives you an uniformed opinion.
My trani has been flushed twice, I have over 400 rwhp/lbft on an A4 and have never had a trani related problem. I'm sure you think its only "luck".
Last edited by 99 vett babycar; Oct 14, 2009 at 12:45 PM.
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Instructor
Joined: Aug 2009
Posts: 226
Likes: 2
maybe you should advise GM of your opinion - currently they do not agree with you.Its hard for me to believe that they force thier dealers to buy the flushing machine, for a lot of money, just to screw up transmissions that might still be under their warranty.
Of course you're correct in saying that if you bring your car top some A-hole who thinks he's a qualified, up to date mechanic and in truth is not, it is likely that he'll cuase you problems - but that's also true even if he just adds oil to your car or gives you an uniformed opinion.
My trani has been flushed twice, I have over 400 rwhp/lbft on an A4 and have never had a trani relatred problem. I'm sure you think its only "luck".
Of course you're correct in saying that if you bring your car top some A-hole who thinks he's a qualified, up to date mechanic and in truth is not, it is likely that he'll cuase you problems - but that's also true even if he just adds oil to your car or gives you an uniformed opinion.
My trani has been flushed twice, I have over 400 rwhp/lbft on an A4 and have never had a trani relatred problem. I'm sure you think its only "luck".
no jackass, thats exactly the point im making. most people dont have the proper equipment or the training to execute this procedure properly. and if he was looking to do it himself, swapping the pan fluid frequently would be the best course of action.
its that simple. there is no debate.
wow 400 hp is so impressive. how much of the work did you do yourself? the way you stated it, sound like you didnt flush your tranny yourself, but im glad your an expert on the subject.
i stand behind my original statement, as its my informed opinion, that in most cases flushing simply isnt necessary.
Last edited by CoreyZ06; Oct 14, 2009 at 12:22 PM.
Race Director
Joined: Jul 2007
Posts: 10,959
Likes: 2,641
From: Texas Hill Country
the argument is not that the flush will loosen debris, it's that the new detergent rich fluid will "clean" the debris into a new place in the valve body and cause problems (which sometimes it does). the argument is whether or not to change the fluid in a trans that has significant mileage and has not been changed before. i say if you have 75K+ miles on the car and haven't touched the trans fluid before, leave it alone. if it is part of your regular maint, do it!
Thread Starter
Instructor
Joined: Jun 2009
Posts: 175
Likes: 0
From: North Texas
I knew this would happen....Here's my specific story, Its a 99 A4, w 80K on the clock. I recently purchased the car from the original owner and have no idea if the fluids have been changed or not. I am not currently experiencing any major problems (this is my 1st auto) the only thing that I have noticed is when i am slowing down and the transmission is downshifting accordingly, it sometimes doesn't downshift perfectly...again, a 10 year old car w/80K is not going to be perfect by any means.... So right now, I am leaning towards checking the existing fluids, if they are still red, then simply swap fluids and be done with it (peice of mind on my part), but if the fluid is nasty and needs more than a simple change, should the dealership be the place to go, or should I do some more digging and find a reputable mechanic that has previous experience and let him do it?
Isn't this fun!!
