Ford Ranger Engine Problems

Excess sealant suggests sloppy workmanship. You might like to mention it to your dealer and suggest they disassemble the diff and put it back together without excessive sealant that could cause issues down the track, or you could let it go and hope it doesn't cause any problems later on. If it was the engine I would want to fix it, but in the case of a diff I'd be tempted to report it in case something does develop in the future, and let it go.