Brian Meek
Member
Hello folks,
I'm hoping someone can shed light on a 1st Gen Expedition puzzle involving a previously-overfilled 4R100 transmission on a 2001 4x4 with the 5.4 V8. When I did a drain & fill, I miscalculated and overfilled it. My daughter was in a hurry to leave and took off before I realized that I may have put in too much MaxLife ATF... She noticed that the Expedition then "seemed sluggish" - like it took more throttle to get moving and up-to-speed, although it shifted fine through all the gears as normal. Gas mileage wasn't noticeably changed.
A few hundred miles and a few weeks later, I got the chance to check the ATF level and confirmed I had overfilled (and confirmed the "sluggish performance"). I drained out a couple quarts via the ATF cooler line and topped it off carefully so that the level checked out exactly right when up-to-temp. Unfortunately, the "sluggishness" persists! Oddly it seems to be running fine otherwise, no codes, it just doesn't roll like it used to.
Any ideas?
I'm hoping someone can shed light on a 1st Gen Expedition puzzle involving a previously-overfilled 4R100 transmission on a 2001 4x4 with the 5.4 V8. When I did a drain & fill, I miscalculated and overfilled it. My daughter was in a hurry to leave and took off before I realized that I may have put in too much MaxLife ATF... She noticed that the Expedition then "seemed sluggish" - like it took more throttle to get moving and up-to-speed, although it shifted fine through all the gears as normal. Gas mileage wasn't noticeably changed.
A few hundred miles and a few weeks later, I got the chance to check the ATF level and confirmed I had overfilled (and confirmed the "sluggish performance"). I drained out a couple quarts via the ATF cooler line and topped it off carefully so that the level checked out exactly right when up-to-temp. Unfortunately, the "sluggishness" persists! Oddly it seems to be running fine otherwise, no codes, it just doesn't roll like it used to.
Any ideas?
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