Apologies in advance about this query as I'm sure it's cropped up many a time. Confess to be struggling with navigating site. Anyway, got a 55 plate defender 90. Drivers side wiper arm seems a bit slack and doesn't always return to resting place properly. Sometimes it even goes a bit too far over when in use. Passenger side is fine. Before I start stripping out the dash to investigate I'd like advice on possible cause so that I can get the right parts in readiness and get it all done in one go. Any suggestions very much appreciated. Don't mind getting parts that might be surplus but don't want to strip her down and find I need something I've overlooked. Thanks