2001 GMC serria 5.3. After changing transmission fluid truck will not go in to 2nd. I put everything back on correctly.
Might not be gettin fluid to the pump. Was the new filter the same as the one you pulled out, was the neck the same length. Check to make sure the filter was inserted al the way up. If you don't want to pull the pan, crack a cooling line on the tranny or at the rad to check for pressure, briefly start the truck. If oil was leaking from the fitting your pump is working and I have no idea what happened. If there is no fluid or fluid with no or low pressure check the filter.
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