Overfilled 4L60E...How Will It Perform?
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TECH Resident
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From: Ft. Lauderdale, Fl.
Overfilled 4L60E...How Will It Perform? If you overfill a 4L60E transmission with fluid, say a quart or so more than it should have, how will the transmission react? I have an aftermarket dipstick and question its accuracy. Thanks
FormerVendor
Joined: Jan 2008
Posts: 67
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From: Richmond, Texas
We have run them up to 1 qt over with no side effects. If you overfill too much it will puke out from the breather tube. It's way better to err on the over fill side than to not having enough fluid.
Thanks Mike! 
This is what I've been told, error on the side of overfill by a little, so if you look at the dipstick run it at the full line not in the middle or bottom. I was told if you it to full not only will it puke out the vent tube but can cause the oil to froth or foam because it's getting whipped by the internals.
