Hello all! I have a 96 GMC Sierra. As of lately it has been jerking when shifting into drive and 2nd gear. As I try to go faster it either stays in 2nd or 3rd gear. I can still get up to 70 mph but I can feel the truck resisting. Back story: I bought this truck from a gentleman who selling due to a broken U joint that caused the transmission housing to Crack. (4L60E) the transmission was gutted and placed in a new housing case.

So we put the OBD II and it threw code P1886. Transaxle timing shift solenoids. We replaced all shift solenoids (besides one as we thought there were 4 but there were 5). After that the truck ran like new. Shifted like butter, effortlessly. This lasted a day and half and now we're back where we were.
Could the new solenoids be bad? What is the problem? help!!!