UPDATE-Upallnight was sort of right, spraying some silicon spray in the latch did help a bit , I was able via the keyfob unlock button to unlock the rear but noticed I had to pull a little harder to lift tailgate up, and on closer inspection the latch was not fully open which is why I had to pull up harder ( in turn when closing it from this state it would not fully lockdown and pull the tailgate to original position)

Seems that via the keyfob the latch does not fully open, whereas if I press the button on the actual upper tailgate it does...worse comes to worse gonna have to make do without the keyfob for specifically opening the rear only...strikes me as odd though that via key latch is not happy yet via manual method of touching upper tailgat button in disengages fine...all posts on the site say if the latch is broke its broke-or the spring has broke

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E53 X5 3.0d SUV prod.date 11/2004 eng.variant M57N Europe Right hand drive N