Celestron 9.25 Advanced GT tight

[12_monkeys]

Hoping someone might be able to shed some light on this situation. 
 

Recently purchased a secondhand 9.25 Celestron telescope. It was only used a handful of times prior to the owner passing away. When setting it up the declination axis seems excessively tight so it’s making it hard to balance it. 
 

I’ve tried removing it and re-greasing, which helped. Also adjusted the tension ring but made no difference. 
 

Have I missed something blindingly obvious? 

[knobby]

If the Advanced gt mount is anything like the AVX that superseded it then It is very hard to make dec loose. I balance mine on a pencil and mark the dovetail before mounting it.