i went and had my filter done change of fluid also now the transmission wont shift from 2 to 3 or 4 can anyone help

also i need to know how to take brake light switch off thanks

What are you driving??

tranny or switch
 

iam driving my camaro now but my 2000 4x4 blazer is down with this problems

When you are asking for support with your vehicle, knowing the vehicle info is crucial!

So you have no upshift out of 2nd. Does it slip or just stay in 2nd gear without attempting to shift?

A "No 2-3 Shift or 2-3 Shift Slips, Rough, or Hunting" condition could be caused by:

• Internal damage to the torque converter
• Oil pump stator bushings scored or off location
• Valve body assembly 2-3 shift valve train stuck, gaskets or spacer plate incorrect/mispositioned/damaged, 2-3 accumulator valve stuck, or face not flat
• Input housing assembly 3-4 clutch or forward clutch plates worn, excessive clutch plate travel, cut/damaged 3-4 clutch or forward clutch piston seals, porosity in input clutch housing or piston, 3-4 clutch piston check ball stuck/damaged/not-sealing, restricted apply passages, forward clutch piston retainer and ball assembly not seating, or sealing balls loose or missing
• 3rd accumulator retainer and ball assembly not seating in transmission case.
• 2nd apply piston seals missing/cut/damaged in 2-4 servo assembly.