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Tranny Flush: Yes or No

honeyp1

New Member
Joined
Jun 6, 2010
Messages
8
Location
Raleigh, NC
:help:My 07 has 110k miles. All work done at the dealership, I am not having any problems w/the tranny. Do I check the fluid and based upon the condition decide to flush or change the fluid w/new filter. The manuals said to change and replace filter. I have several post and still don't know what to do. Can the flush be as harmful as stated? Will I risk damaging a good tranny at this point so far? Help...
 
I only ever had one tranny flushed in all my years...and the car ran like a turd afterwards.  All sorts of things can go wrong.  Firestone broke the lines while hooking up their machine, but replaced them at their cost and didn't charge me for the flush (which is actually a vacuum-draw).  You run the risk of sucking debris into the passages of the tranny and not having good shifting or idle after.  Others will have good stories to tell.  To me, if it ain't broke don't fix it...replace it with bigger...as per my signature.
 
honeyp1 said:
:help:My 07 has 110k miles. All work done at the dealership, I am not having any problems w/the tranny. Do I check the fluid and based upon the condition decide to flush or change the fluid w/new filter. The manuals said to change and replace filter. I have several post and still don't know what to do. Can the flush be as harmful as stated? Will I risk damaging a good tranny at this point so far? Help...





X2. If you have never done a flush in 110,000 miles then now is not the time to start. Flushing done starting at about 30k and then every 30k after would be fine but too much debris has been built up and moving that around with a flush now could cause problems. Fluid and filter change would be a good idea.
 
Forward flush be fine. Change fluid and filter at a minimum.
 
I've heard that the high pressure "back flush" that the dealer does is not good and people have had trans problems soon after.

To me the best way to do it is to to find a oil change shop that has the "fluid exchange" equipment, it does not use high pressure and will not dislodge particles. They disconnect the trans line at the radiator and that line goes to the reservoir of the machine and they hook the other line from the reservoir with the new fluid (you can bring your favorite fluid) to the radiator fitting and as the old fluid comes out the new goes in at the same pressure, same direction and you get 90 plus percent new trans fluid even the torque converter.

Then you drop the pan and install a new filter and you good to go for another XX,000 miles..

I've done my vehicles this way for many many years with zero problems..


Here's a good explanation...

http://mdhmotors.com/transmission-flush-when-and-when-not-to-flush-transmission/




 
Thanks for the link Randy.

(y)

All good information, but I especially like the last section.

The take away is if you are already seeing a lot of debris on the dipstick along with a burnt smell, DON'T FLUSH.

Your transmission is already doomed and spending money on a fluid change or flush will most likely do more harm than good.

Not to mention be a total waste of time and money.

Now is the time to start getting ready for at least a rebuild, or is some cases, replacement.

It's coming.

Maybe sooner.

Maybe later.

But it's coming.

So get ready, while you have the chance.

A simple change in fluids never fixes worn out or damaged mechanical parts.

That's just wishful thinking from someone who hasn't come to grips with the fact their transmission has already started the failing process.
 
I tend to not do anything not stated in the maintenance schedule unless I have to...  Mine says change the filter and fluid which I have had done twice already...  Both times I've paid someone else to do it, but I wish it was an easy DIY project.
 
FWIW, I've seen this many times.

I just simply have my mechanic drop the pan and replace fluid and filter every spring-ish.

Done it five times now. I have about 145K miles on the truck.

 
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