is there a way to remove the tmobile logo on startup and replace it on sgh-t959v?
What ROM are you running?
There is a method to edit your param.lfs file to include a custom image. You'll need to flash the new param.lfs file with heimdall or odin to get the new logo. It's fairly risk as param.lfs contains other files necessary for the phone to work correctly besides the images, but it's totally doable.
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