Pals running out of steam? (5)
I believe the answer is:
mates
'pals running' is the definition.
'mates' can be an answer for 'pals' (I've seen this before). I am not certain of the 'running' bit.
'of steam?' is the wordplay.
'of' indicates an anagram (the answer comes from or 'of' the letters).
'steam' is an anagram of 'MATES'.
'out' is the link.
Can you help me to learn more?
(Other definitions for mates that I've seen before include "Chums" , "Pals, pairs" , "Friends among the ship's officers" , "Pals or spouses" , "Naval officers'" .)