Harry Redknapp's side slipped to the bottom of the Premier League when they were beaten 1-0 by Alan Pardew's side on Saturday.
The London club have lost all six matches on the road in the top flight and also suffered a shock League Cup defeat at League Two side Burton Albion.
Midfielder Fer suffered relegation with Norwich City last season and knows he could get that sinking feeling again if Rangers fail to start picking up points on their travels.
He told the club's official website: "Against Chelsea we could have had a point, against Southampton we could have had one and again against Newcastle.
"We have played some good games away from home but we haven't been able to take anything from them.
"We need to start playing as well away from home as we have done at home.
"We will need to start getting something away from home if we are to stay up. We know that's important and it’s something we are keen address quickly.
"We have two home games coming up against sides around us [Leicester City and Burnley] and we have to win them."
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