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How many quarts if changing fluid/filter in trnsmission

100K views 21 replies 12 participants last post by  eliteroger 
#1 ·
I plan to do this soon, I believe it is about 5-6 quarts. Has anyone done this yet. Thank you.
 
#3 ·
I can't stress this enough ...Don't over fill the trans ....and please start truck after 4 1/2 quarts put trans in 1,2,3,4 N R 3-5 times then N with e brake on check the fluid then add the rest or top off ...I have seen 1200 mile trucks low 1+ quart and shifting hard and slip bang ....
 
#5 ·
how many quarts do these trucks hold total? I want to do a whole system flush before too long here, and just want to make sure I have enough with me. I'll also be adding a trans cooler at the same time...any reason this should hurt, by cooling too much? I'm debating buying a deeper trans pan from TCI that holds an extra 3 or 4 quarts or so of fluid. It also has a fitting for a drain plug, and a bung fitting for a trans temp gauge, which I kinda already have installed, but only the lights are hooked up for now. I'm also debating a shift kit for mine, but I don't know jack about trannies, and don't want to mess somethin up. I've done my fair share of wrenching, just not on transmissions. I saw where transgo makes a kit for pretty cheap, but I'm not sure how to install everything in it. is it difficult?
 
#7 ·
No, I don't have a flush machine. I had a debate about this tonight at work (advance auto) with a 35 year master mechanic, and manager. See, on here somewhere, and I'm looking for the link now...I saw that you could "flush" your trans by taking off the cooler line going into the radiator, and turning the car on, and letting the transmission pump the old stuff out, while you pour in the new stuff. The article said if wouldn't hurt it, if you just kept up roughly with what the trans was pumping out. So, I ran this by the manager, who said don't do that, you'll ruin the transmission. At first I didn't know who to believe about it, the article, or my manager. Now, I trust darrel, my manager, and I realize any idiot can get online and post a how to article...so, I think if I do have it flushed, i'll take it to a shop and have a bilstein flush done. Anythoughts? Ok, I've been reading through some old posts, and it looks like everyone says it won't hurt it, which is what I thought, and darrel is sometimes known to spout out nonsense. Now...will the Torque Converter be emptied too??? or will it keep the same old fluid in it? Also, I've already bought 12 quarts of mobil one synthetic ATF. This should be fine...but just to check, it should work ok, right?
 
#9 ·
I'm with Darrel...It may work, it may not work. You may cause damage, you may not


I wouldn't risk it...theoretically, you should be replacing the fluid at the cooler line going back into the transmission :yes: I don't think it will work, but I'm not looking at a flow chart at the moment. Plus, you're not flushing out the cooler if doing it this way (& you're going to make 1 hell of a mess)

And, you aren't replacing fluid at the same rate it's pumping out

It's your tranny; just make sure you have $$$ aside for a new tranny
 
#10 ·
yeah...that's kinda what I was thinking. he also said I wouldn't even be draining the TC...it gets fluid pumped in, and beyond that, it has to actually be flushed out with pressure. Not just by adding fluid as the tranny pumps into a bucket. Where would I get a drain plug kit? Do those work, or what's the deal with those? I also have a gauge I'd like to hook up for trans temp, just to keep an eye on it. TCI makes a deeper pan with a bung fitting for a pressure sending unit...eventually I'll get that, but it's like 200 bucks IIRC.
 
#11 ·
Yeah, any 'idiot' can post a How-To article. :rolleyes: Well you know what, it worked fine on my older 2002 TB. I'm certain that others have done theirs that way and it worked just fine. In fact, when I did it I used the process described by several other members on here, and I'm confidant that if you do it correctly and are diligent about not running it dry then you'll be fine. The pump is a gear-rotor pump and so long as the supply is there it will pump in the equivalent of what it pumps out, hence why you should make sure you're pouring it in as it pumps it out.

If I was a repair shop mechanic I would certainly never recommend anyone do anything at their place....that'd be money out of my pocket.

FWIW - there are plenty of reports on the internet about people who had their transmissions flushed and it caused problems that did not exist prior. Something about loosening deposits, etc.
 
#12 ·
My 1984 Camaro a with 700R4 began shifting weird due to some sort of contamination in the fluid causing the governor to get stuck. I put in two cans of Seafoam transmission tune and drove it for a few days until the transmission seemed to be shifting ok. Then I dropped the pan and replaced the filter. To flush it more completely, I removed the top transmission cooler line from the radiator and installed an appropriate hose fitting and about 5 ft. of clear vinyl tubing running to an empty gallon jug. I refilled the transmission with the specified replacement quantity of synthetic ATF (5 quarts I think) PLUS four extra quarts. I started the engine and let it run until it filled the gallon jug. I reattached the cooler line and started it up again and checked the fluid level hot, idling in park. Had to add about another half a quart to get to the Full line on the dipstick. Haven't had any shifting problems since (two years). May not be the most perfect way to flush, but it worked for me, and it's considerably cheaper than a replacement transmission!
 
#13 ·
Hi, I just read this on BITOG:

"I have used a 2-bucket method for flushing. The escape has a tranny plug, so dump the oil and replace 1 gallon.

Extend the inlet and outlet cooler lines, one in each bucket. Dump about four gallons of ATF in the bucket with the return line to the tranny. Start car, move shifter through the gears a few times. Stop car when fresh oil bucket is almost empty. Check ATF level per mfgs. instructions and adjust if needed. Discard old oil properly.

This method will completly change out the crummy old fluid and ensure the tranny never runs low on oil during flush."


Is this a possible way of changing out fluid for the TV for those who are in doubt of the "How-To"?
 
#14 ·
Maybe, maybe not. Guess you have to see if there's any suction from the gear-rotor pump. I'd be willing to bet that it relies on the return pressure, or the ambient pressure in the reservoir for its oil supply. So placing the one line in the bucket may not do anything.
 
#16 ·
And personally I would say GM is FOS; changing the filter at 100K is a BAD idea if you want your trans to live much past that. There are lots of reports that unless you do a pan drop and filter change at like 15-20K that you will have major issues later on. I can vouch for this firsthand, I waited till ~50K and that was a mistake. My pan was caked in clutch dust at 50K (and that was before I started driving hard, yes my driving habits have gotten more aggressive since Ive started modding my TB:laugh: ). And, as long as you have the pan down to drain the old ATF out, the filter is staring at you right there, its ~12-15 for a filter and you might as well replace it anyway.

Thats my POV, take it or leave it. I just think 5qts of ATF and a $15 filter for a total less than $40 is cheap insurance so you dont have to have your transmission overhauled before 100K.
 
#17 ·
OK...Mobil makes a sythetic ATF, and I've got like 15 qt's of it. I know they say now that you can mix synthetic oil and conventional in the crankcase...but can you do it in the trans too? Just to be safe...I could drop the pan, drain the fluid...add the 5 qts back into it, of synthetic, if it mixes. Then, I could drive for a while, and repeat, several times until most of the old stuff would be out. This would kinda be a PITA though...and would waste a lot of expensive fluid. Or...does anyone think I could take my truck to a shop, and give them my fluid, and have them flush out the old crap, and replace it with the new synthetic that I already have? I definatly want to go with a synthetic ATF...way more resistant to heat. Also...would this controversial flush method empty the TQ, or not? Darrel, the guy I work with, says it wont...but I don't know. I've got half of a mind to take it to a shop, and bring them the fluid, the deeper TCI pan, and a shift kit, and say, put all this, on that trailblazer there.
 
#19 ·
Darrel, the guy I work with, says it wont...but I don't know. I've got half of a mind to take it to a shop, and bring them the fluid, the deeper TCI pan, and a shift kit, and say, put all this, on that trailblazer there.
When I did the flush method I wrote about in the article, I removed pretty much 11-12 qts right on the nose (I had a 5 gal bucket, it had graduated markings so I was able to measure how much I had removed.). The Haynes manual I have states that full capacity, including TC is 11.2qts, and what I've heard on here is 11-13 qts. If you have the small pan, several on here have stated it should be around 9 qts. I am inclined to believe that you will get nearly all of the fluid out of the entire transmission. There will of course be some left, however it's a negligible amount. I'll tell you that when I changed mine at maybe 74,000 miles or so on my 2002...it was nasty. Nearly black fluid and the pan had a layer of black grime on the bottom of it. After I changed the fluid the truck shifted more smoothly (maybe it's psychological, but I swear it did). Keep in mind that there is little to no load on the transmission while it idles in park. I did the change and wrote the How-To based on what I learned from other members here when they did the same thing, and none of them had reported any problems (that I am aware of). If it makes you nervous about doing it, then I would definitely pay someone to do it for ya.
 
#20 ·
I know this is an old thread, but just wanted to put my 2 cents in, because I've actually done the "flush" by removing the line going to the radiator. It worked with great success, and I drove about 70,000 miles with absolutely zero issues with my transmission. And I didn't baby it either. I drive like an animal. I may have gotten lucky, but I plan on doing this again very soon, with my current trailblazer, and will do a write up on it.

My only suggestion, and somthing I highly recommend if your doing the radiator "flush".
Don't let the car run for more than
8-10 seconds at a time, the transmission flows very quickly, and it seemed virtually impossible to pour in the same amount that was flushing out.
I didn't attempt to get every last bit of old fluid out, I just wanted a good portion of old fluid removed. Don't over do it.
 
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