How dirty should my ATF be before it's changed?

[SteveD2]

A few days ago I drained the pan on my automatic transmission (jeep cherokee) and refilled with 2.5 quarts of fluid...but I beleive the total capacity is 12 quarts. I overfilled it a little bit, so today when I took out the extra fluid I compared it to new fluid. How dirty should I let it get? This is a picture of the fluid on a paper towel, the left is clean, right is dirty. They look more different in real life than in the picture...do you think I need to change it again?

 

[mrchecker]

I go by smell more than color on ATF. If it smells burned, change it regardless of color. If it's brown but still smells OK, I'd still change it. Usually it smells funny before it turns brown.

 

[sbc350gearhead]

When in doubt......change it out.

 

[Amkeer]

Looks OK. I would change it again in the next oil change interval.

I just recently changed mine about 5,000 miles apart since it was alot nastier than yours.


Daily Drives:
-2003 Toyota Tacoma PreRunner XtraCab, Impulse Red, Peppy 2.7 Liter 4 Banger, Running Mobil1 Synthetics SS 5W-30.
ODO 5800 Miles.
-1995 Toyota 4-Runner, Evergreen, 3.0 V6, Running Mobil1 Synthetic SS 10W-30.
ODO 82900 Miles. (Switching to GC next)

 

[RavenTai]

2.5 of 12QT? wow I usually don't like those expensive transmission flushes but in your case it may be the only way to get a good fluid change,


dropping the pan and pulling the cooler lines gets 16qt witch is 2/3-3/4 of the fluid in my transmission


if it were mine I would change it, I like to see cherry red on the stick, I drain from the plug and change the external filter every 25k, drop the pan and change the internal filter every 50k, but what you have there looks better that 90% of the cars out there and will probably be just fine for a wile

 

[unDummy]

ATF should never get dirty.

When its dirty, its overdue.

 

[crashz]

ZmOz,

A lot of people don't realize that the torque converter contains most of the ATF in the tranny. Some vehicles have a TC drain and some don't, but draining this will probably yeild another 8-10 qrts. Thats where your dirty burnt fluid is. It would take you 30 drains from the pan to clear up that fluid and still you will not get everything. Its best to drain the whole system. Using the cooler lines and the tranny pump to pump the fluid out is one way, but be careful not to burn the pump out by idling with no fluid in the tranny. On vehicles that don't have a TC drain, I shut the fuel pump off and use the starter to pump the fluid out.

 

[SteveD2]

quote:

---

Originally posted by Kestas:
I'm missing something here. You only changed 20% of the fluid, and you're asking why it's not as clean as new? I would expect the color to be rather close to the old fluid. If you want to do better, perform a fluid exchange. I think the procedure has been written a few times on this site.

---

I know the fluid wasn't going to be as clean as new, I'm asking if it's still dirty enough to change it again. I have heard ALOT of really bad stories from people with my particular transmission about getting the thing flushed, so I will not be doing that.

 

[unDummy]

It won't take 30 drains.
I have no opinion on the overrated "paper towel" analysis.
If you really want to know, get an ATF UOA.
Since ATF is cheap, change it again and again and regularly.

Otherwise, since you said it took 12 quarts, buy at least that many and do as many drain/refills(with driving in between) required to use those 12 quarts(or more).

How did you drain the pan? why do I want to think that it holds more than 2.5 quarts?

 

[SteveD2]

My transmission pan has a drain plug.

Only about 2.5 quarts came out...and my repair manual says that's about right with the whole thing holding 12 quarts.

 

[Bluestream]

If you go to this page, there is a neat QBASIC program for finding out how much fluid you have to drain and fill to get most of the old ATF out.

http://www.nmia.com/~dgnrg/page_12.htm

Just click on: FLUIDCG1.EXE and click open.

Be sure to enter the total capacity of your transmission, as the program defaults to BMW 8.1 quart capacity

 

[Kestas]

I'm missing something here. You only changed 20% of the fluid, and you're asking why it's not as clean as new? I would expect the color to be rather close to the old fluid. If you want to do better, perform a fluid exchange. I think the procedure has been written a few times on this site.

 

[Leo]

That seems pretty clear to me. When I drained the ATF from my moms Mazda 323 early at 30,000ks (due for dealer replacement at 60k), on a paper towel it wasnt red at all. More of a transparenty light brown...

Glad I changed it out!

 

[Kestas]

quote:

---

Originally posted by ZmOz:
I have heard ALOT of really bad stories from people with my particular transmission about getting the thing flushed, so I will not be doing that.

---

Are you sure you won't reconsider? I too don't care for having a shop exchange the fluid. I heard the pressure they use can blow the seals.

I use the shadetree technique where you disconnect the return line and iterate between pumping out three quarts at a time by starting the engine and filling up with three quarts until all the old stuff is pumped out. I don't see any harm by using this method. Others say it's not good to run it out of oil this way, but I don't see a problem doing it, since it's only momentary and the parts are still wet with oil.

I'm skeptical of claims by people who testify they had a problem after doing a certain procedure. One has to wonder if they didn't try to perform maintenance (such as flushing a transmission or ps system) because they were promted by a minor problem, only to have the system completely break down shortly afterward, and then they blame the procedure, completely omitting the fact that there was a previous hiccup with the system.

[ November 14, 2003, 03:12 PM: Message edited by: Kestas ]

 

[Cujet]

I change the pan ATF with synthetic at every oil change (5000 mi). I also have a drain plug on the pan. The 4 quarts are only a fraction of the 14 my system holds. However that is a good way to keep it fresh. The fluid always looks brand new. Doing this has solved the trans failure problems I was having, as my vehicles are seriously abused.

Chris

 

[Robbie Alexander]

quote:

---

Originally posted by ZmOz:
-*-* I overfilled it a little bit, so today when I took out the extra fluid I compared it to new fluid. How dirty should I let it get? -*-*

---

Your link is bad.
Anytime the ATF Changes color at all, it's time to change the fluid. And anytime it changes smell, you change it too. Anytime it does not look like Brand new THEN CHANGE IT.
i WOULD GO FIND A bg FLUSH, AND PAY THROUGH THE -*-/* NOISE AND FLUSH IT ALL OUT. then if you want, do short changes of say 15-30K because the normal changes don't get all of it out.
Me if I had the money I'd do 10-15K changes on the fluid.... Better yet, PUT and EXTRA COOLER on there, and it will stay clean forever... least a long time/

 

[TheTanSedan]

I've done September changes on our 2001 XJ with the Aisin-Warner O/D trans (AW-4), at about 9k, 38k, and now at 60k (2600 miles/month, roughly).

This time added B&M #70268 cooler and MAGNEFINE filter downstream of radiator.

(This link details power-steering system, done similarly, at same time.

http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic&f=16&t=000657#000017

Trans was cleaned with ARX according to directions first. Then, a flush with a full twelve quarts of SCHAEFFERS #204s Dexron-Mercon Supreme blend. (System holds 8.45 quarts; I saved the last few quarts flushed for a leaky trans on another vehicle).

At around May 1st of this coming year (about 18k miles more), will flush/replace filter to be extra certain of cleanliness. Will do a UOA one year after that.

Otherwise, at least do annual changes of ALL fluids for best performance: brake, steering, trans, rear end, coolant. Lubricants get old, and why take a chance on "premature" wear when changes are so easy?