Shuddering torque converter lockup 40 to 50 mph.
Can’t figure it out! I Put a new cooler, new solenoid pack still shudders and locks and unlocks between 40 and 50 mph. Rpm goes up 400 and back down in and out till you get passed 50 you get back into that 40 to 50 and does it again. Need help codes p0218 and p0700.