truck hitting to hard
What is the idle speed? Too fast can cause this, possible stuck ISC, other things could be bad shift solenoids, excessive pump pressure inside the tranny, internal buffer failure inside the TCM, so if your idle speed is normal then I would recommend that you take it to a tranny shop so they can plug in and run the tests on the solenoids, internal pressures and TCM control. You don't what to break a u-joint or yoke with it slamming into gear.
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