4L80E Transmission Problems - 99 Suburban 3/4 ton 4x4 454
D*mn chebby is giving me fits. Three different occasions now the tranny has had "issues" - won't shift until 3,000 rpm and then it shifts HARD. Seems to happen when I've driven it for a few hours, then stopped briefly (ie, gas stop) then when I get back on the road, it does it. Will be fine when I get in it the next day.
Trans has 100,000 miles. Used for some towing but not abused. Need to use it to tow 3-4 cars cross-country this summer, so I need the trans to be 100%.
Has had recent service, fluid, and filter change. Fluid level is fine. Has a trans cooler. This hasn't happened when towing, and have towed with it since it's happened with no problems.
Any guesses or suggestions? Should I take it to the dealer and have them scan for codes?
Guess if it needs a rebuild I'm looking at $1500 minimum, right?
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