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Black Tranmission Fluid!

It appears I have neglected my tranmission. I’m told I have black tranmission fluid. Mechanic advised me NOT to change it at this point reporting he did the same thing once and tranny died 300 miles later, explanation high level of detergent in new fluid would eat away anything that might be left of clutch plate and various transmission parts. Is this good advice? Suggestions? 2001 Toyota Camry 4cyclider automatic 212,000 miles plus one broke car owner. Thanks!

No, I would not follow his advice.
The transmission that failed 300 miles later would have failed whether or not he changed the fluid, simply because it had been neglected/abused.

In terms of your sadly neglected transmission, consider a trans fluid change to be a Hail Mary Pass, sort of. It is a gamble that might get you a few thousand more miles from the trans, or it might fail tomorrow, and nobody can predict which way it would go.

If I were you, I would go to an independent transmission specialist, not to a regular mechanic, and certainly NOT to a chain operation like AAMCO, Lee Myles, Cottman, Mr. Transmission or the like. Tell them that you want to have the pan dropped and cleaned out, new fluid, and a fresh trans filter. If you are very lucky, this will buy you some time. If you are not lucky, the inevitable will take place soon.

And, just for future reference, no matter what the mfr’s maintenance schedule says, trans fluid (and filter, if so equipped) needs to be changed every 30k miles or 3 yrs, whichever comes first. When this is not done, trans failure can take any time after ~90k miles, and is pretty much of a sure thing after ~120k miles, so while you may not have maintained it as you should, you have still beaten the odds by a great amount, in view of your odometer mileage.

Black transmission fluid could be caused by sediment from worn plates or high temperature in the transmission. It does not sound good. Have you been adding fluid? You also have to use the reccomended type of fluid. Each auto maker specifies what fluid to use. Using the wrong fluid can be bad especially if you mix fluids
There is a trans cooler in the radiator. Sometimes flushing and refilling aggravates the problem I was told by my dealer But I had it flushed and it is ok…
cubpilot

Black transmission fluid likely means the trans is going to be dying soon so stay close to home until this is repaired.

Your mechanic is recycling an old wives tale to you about the new fluid finishing off the transmission. The new fluid is just the scapegoat for something that was going to occur anyway.

You may try the following test. It may be helpful…Using a long flexible plastic hose insert it down the trans dipstick tube. 4 to 5 feet long is good. suck out about 3 or 4 ounces and place the fluid in a narrow glass tube or such. let it settle for a few days. The sediment if any, will settle to the bottom then you will possibly be able to see what the sediment is. If there is sediment pour off as much of the upper portion as possible. ( top portion clear?) Add a solvent such as tolulene,acetone,90 per cent alcohol and pour the mix onto a few layers of paper towel and set it outside. Fire hazard>
where most will evaporate. You may be able to tell if the sediment is metalic or fiber with a magnifing glass or just spreading it around.
Cubpilot

P.S. I have done this with engine oil and trans oil. I used some thick blotter paper put one or 2 drops on the paper. (no more)The oil spreads out leaving the impurities in the center. The larger the spot of oil the better the dispercent quality . The darker the center the more impurities are present. Takes a day or 2 tho. I used used a 150x stereo microscope. (Borrowed)

Agree with all…At 212k miles, ANYTHING you do to the transmission is a crap shoot as to whether it exacerbates present problems. Not changing the fluid is not an option as is not changing motor oil that is very dirty. You MAY have related problems changing it…you WILL have problems if you don’t. Take it to a transmision specialist and have it serviced. Independents are not all knowing.