So I got this thing with a blown engine and no insight from the owner as to any other issues. Dropped a low mileage 5.7 in it and runs great. I figured I would do a trans service while I was at it and changed both filters and gasket drained the converter while it was out. The old fluid was very clean and nothing in the pan. I got the kit from O rileys and the filter had a fixed o ring on it the original did not it seats in the trans. It felt ok when I installed it but after firing it up and test driving for the first time it is stuck in 2nd gear trans feels tight and no slipping. Took it and had the codes read got a po700 po846 po876 po888 from a couple of threads that were posted some mentioned the filter not being seated so I checked again there is an o ring in the trans housing that is fixed and then the one on the filter not sure what to do any help would be greatly appreciated .
Thanks