Edmunds Answers



  • karjunkie 09/20/08 6:54 pm PST

    Even BMWs that have sealed transmissions and claim "fluid for life" need regular fluid changes. Transmission fluid will, like any oil, degrade over time and leave deposits on sensitive components of the transmission. I would change the ATF fluid every 50K miles with a good synthetic that will provide superior protection. This is a cheap preventitive measure for something that will cost thousands to rebuild. I use Mobil1 synthetic ATF fluid in my transmission and it is a fantastic product. But even regular ATF fluid and a filter change at every 50K miles will provide you a lot of good insurance.

  • subearu 09/21/08 12:13 am PST

    Change is good for the tranny fluid. However, try to stay away from a "power flush" type of service, which may lead to problems caused by pushing sludge, etc into fluid channels and whatnot in the tranny. A regular drain/fill should suffice. You might not be able to change all the fluid this way, but it will still be changed. Could do a couple drain/fill procedures if you really want to. Cleaning the filter (if applicable) is ok too.

    What color is the current fluid? Is it burned smelling at all?


  • jules3084 09/21/08 6:17 pm PST

    Thank you both for your comments and advise. It all seems to make good sense.

    Currently I don't know the color or scent of the transmission fluid.
    I'm not able to easily sample the fluid. The fill cap on the top doesn't seem to allow drawing off a sample through the top. I may have to use the level check hole and sample there.

    Was it here I read if its color is normal, its safe to change, but if its discolored beware.

    I've read also that the new trans fluid with its high detergent content can wash away varnish, that over time has helped make good seals inside the transmission, resulting in
    seals that don't hold pressure so well anymore after being changed.

    Since 1969 I've had 6 GM cars. All have exceeded 120,000 miles, and not one transmission problem, all without a single transmission fluid change.

    I wonder how necessary this really is? I wish there were some statistics on the matter.

  • obyone 09/21/08 8:41 pm PST

    Your concern about removing the varnish is a legitimate one. However, that is usually related to doing a trans flush. At your mileage it would be better to do a drain and replace filter rather than doing a flush which could lead to additional problems.

    For myself, I've changed the trans fluid on my 2000 Silverado twice and once on my 2002 Yukon Denali with no adverse effects. The color of the fluid was red on all three changes. You should be able to check the color of the trans fluid via the trans fluid dipstick in the engine compartment.

  • tk329 05/03/09 2:04 pm PST

    I took a different route,and purchased a small vacuum pump,just hand one. I then drew a sample of the fluid into a small container,that was part of the pump package $30. I sent the sample off to Blackstone labs,and they send you a pfd file by email. The car had 32,000 miles,and the sample stated that the fluid had the equvalent of 15,000 miles so I did nother. At least now you know where you stand with the vehicle,and your driving habits.


  • nquinn 08/11/11 9:13 am PST

    Except the Chevy Malibu doesn't have an engine compartment dipstick. Epic engineering fail!!! Practically have to take it to a mechanic just to check the ATF. I will not be buying a sealed tranny car again.


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