transmission flush
Race Director
Joined: Oct 2010
Posts: 14,475
Likes: 782
From: Las Vegas NV
Nobody here is saying do nothing. As many cases of failed trannys that there are after a flush, dropping the pan and cleaning/changing the filter is a much safer procedure, that is all and that is my opinion only.
Intermediate
Joined: May 2010
Posts: 30
Likes: 0
yes doing just a fluid flush is the worst thing must do chem flush like the BG TRANS FLUSH KIT to get all the varinsh out of the trans,if you do just a pan drop and filter say your trans holds 13-14 quarts an you just drop the pan and filter and say use lost 4-6 quarts at most and re top the trans now you are back to 14 quarts of dirty fluid again.
Do you change just the oil filter and ad 1 quart of oil or do you change all the oil ?
Do you change just the oil filter and ad 1 quart of oil or do you change all the oil ?
Pro
Joined: Oct 2007
Posts: 679
Likes: 4
From: TremontonUT UT
I have never had any chemicals flushed through my trans but I have had 100% of the oil replaced by the same machine they flush with. Just changing the filter and dumping in 4 or 5 quarts of oil does not get it done. Later! Frank
Racer
Joined: Jan 2010
Posts: 389
Likes: 57
From: Western Arkansas
I owned a repair shop and towing business for several years and have seen a number of transmissions fail soon after a flush (they were usually on the bed of my rollback). Varnish builds up in automatic transmissions. The normal flow of fluid doesn't seem to disturb it. A flush does, and when it is dislodged, it causes problems. I have some very good friends who own transmission shops who refuse to buy flush machines because of this. In my opinion, it's just an upsell opportunity for the shops that have them. I would never do it to a vehicle of mine.
Team Owner
Joined: Sep 2000
Posts: 24,949
Likes: 2,667
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Back to the OP-
If GM says flush it, then flush it.
If GM says just drop pan, change filter, refill; do it that way.
Does GM have any official position on flushes vs changes?
Do any GM cars recommend a flush?
If GM says flush it, then flush it.
If GM says just drop pan, change filter, refill; do it that way.
Does GM have any official position on flushes vs changes?
Do any GM cars recommend a flush?
Team Owner
Joined: Mar 2001
Posts: 25,013
Likes: 79
From: Manitoba/San Jose del Cabo
Cruise-In III Veteran
St. Jude Donor '11
Hmm, I have not been convinced one way or another. Gm says flush, some people here say don't flush, some say do. Some say, drop pan and change oil and filter but leave half the used oil in torque convertor to contaminate the new oil. 
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Intermediate
Joined: May 2010
Posts: 30
Likes: 0
of course transmission shops dont want you to flush it cause the trans will fail earlier taking business from them,transmission care is like taking care of the motor with maintance oil changes try not doing a oil change ever see how long your motor last.
Instructor
Joined: Mar 2010
Posts: 212
Likes: 1
From: Pittsburgh PA
I have a '98 Grand Cherokee 5.9 Ltd that I've done exactly as this, and it's still my daily driver, with absolutely no transmission problems, and it just turned 271,000 miles on the way home from work yesterday...
Team Owner
Joined: Mar 2008
Posts: 21,502
Likes: 461
From: Southern Utah
Le Mans Master
Joined: Oct 1999
Posts: 8,205
Likes: 40
From: Tucson AZ
Instructor
Joined: Feb 2011
Posts: 100
Likes: 0
I have an '05... Had the flush done at the dealership.They switched from Dexron lll to Dexron vl.It appears to work well how ever it appears to run 30* hotter.The service manager says if it fails they'll replace it even though it's out of warranty... Hopefully I won't need to find out if his word is good.
Intermediate
Joined: May 2010
Posts: 30
Likes: 0
The reason the GM dealship switch it is they are no longer allowed to use dex III sine GM came out with synthetic fluid as i mention the most important thing in a trans flush is running a cleaner such as BG product they have excellent produts and only sell to pro shops you can check there web site for a dealer in your area using there products.
www.bgprod.com
www.bgprod.com
