To access them, you'd need to:
1. Remove the transmission: This is a major job requiring significant mechanical skill and specialized tools. It's not something you'd tackle at home unless you have extensive automotive experience.
2. Remove the valve body: Once the transmission is out, you'd remove the valve body, which houses the various solenoids.
3. Identify the specific solenoid(s): You'll need a wiring diagram or a shop manual specific to your truck's transmission (e.g., 46RE, 47RE, 48RE – you need to know your transmission type) to identify which solenoid(s) are causing the problem.
In short: There's no single "location" accessible without major transmission work. If you suspect a problem with a shift solenoid, taking your truck to a qualified transmission specialist is strongly recommended. Attempting this repair yourself without the necessary experience and tools could cause significant further damage.
