2000 torque converter lock

My torque converter is lock/ unlocking between 45- 55mph at steady throttle. No check engine light, or other problem, above 55 its stays locked up and will unlock like it should when you tap the brake pedal or accelrate. Any one have ideas? I dont have a scan tool, would this help? which ones can check trans problems?
thanks

My torque converter is lock/ unlocking between 45- 55mph at steady throttle. No check engine light, or other problem, above 55 its stays locked up and will unlock like it should when you tap the brake pedal or accelrate. Any one have ideas? I dont have a scan tool, would this help? which ones can check trans problems?
thanks

You need to check it with a high end high dollar engine/transmission capable scan tool.
Like Snap-on or GM scan tool.
Check for codes and post back any codes and watch engine running sensors readings.
Engine has to be running right for transmission to work right.
How many miles on transmission and transmission service history?

no engine problems that I can detect,It runs great, temp-oil pressure all normal. I dont have access to that type of code reader,so I guess I'll have to bite the bullet and take it to a tech. The truck has 100k on it, the trans filter and fluid changed at 80k.
thanks for the help I'll post back if I get codes dumped.

no engine problems that I can detect,It runs great, temp-oil pressure all normal. I dont have access to that type of code reader,so I guess I'll have to bite the bullet and take it to a tech. The truck has 100k on it, the trans filter and fluid changed at 80k.
thanks for the help I'll post back if I get codes dumped.

You may have todo more than read codes.
Like watch transmission dats readings.
Good Luck And let us know how it goes.