Moan making good thunderous sound (7)
I believe the answer is:
grumble
'moan' is the definition.
(I've seen this before)
'good thunderous sound' is the wordplay.
'good' becomes 'g' (abbreviation).
'thunderous sound' becomes 'rumble' (I've seen this in another clue).
'g'+'rumble'='GRUMBLE'
'making' acts as a link.
(Other definitions for grumble that I've seen before include "Express dissatisfaction" , "Complain, protest" , "Moan" , "Murmur with discontent" , "what Meldrew does" .)