Aright so we bought this truck second hand on the 31st of October and the previous owner said it just needed a left strut but that's not the problem the truck did not have issues until early April but here's the the thing the truck would be in first then would jerk forward when up shifting or downshifting and would jerk very violently like if you just got rear ended going like 40kmh and the rpms will shoot way up like it's trying to shift but won't I noticed that it won't like catch gears the Mechanic first said his scanner showed up saying it was 2 solenoids but he checked them all and said they were fine so he said it was probably the computer in the truck (ECU) so we paid about $1200 for the part he put it in and said the problem was fixed because he test drove it and said there were no problems the jerking and stuff stopped so I went to pick it up but sure enough it started doing it again but worse now he said it's the transmission sensors and solenoids what do you think it is?
It may sound like a simple suggestion but I would recommend checking the transmission fluid level to be sure that it is within specification as a low transmission fluid level can also cause some of the issues you are experiencing.
Another possible cause of jerking while shifting would be faulty rear struts or a faulty transmission mount however neither one of these parts would cause the transmission to slip just a jerk and a hard shift. The solenoids are a possibility but I am not sure how the mechanic checked them once and they were ok but now he is saying that they are not.
I would recommend having a qualified mechanic, such as one from YourMechanic, inspect the jerking symptom you’re experiencing by testing your transmission solenoids using the manufacturers recommended procedure to verify this diagnosis.