Central line middle of the night train?

[BahrainLad]

I live just north of Snaresbrook station and the last couple of nights (hot, windows open) I’ve been woken up around 4am by quite a noisy train going past - different to a normal tube. I presume it’s an engineering train of some kind but Is there any way of finding out?
I’m about 50m from the line and normally sleep through the last/first trains with no issue but clearly this is a different sound so my brain is waking me up!

I think some months ago some track work was being done too.

 

[Lewlew]

If it's been a few nights in a row then it'll likely have been the rail grinder (smoothes out any defects in the running rails). It normally stables in Woodford sidings when out that way.

 

[Dstock7080]

Indeed Rail Grinder working on 500m Leyton-Leytonstone EB last night.

 

[BahrainLad]

Interesting! Thanks very much all. Do you know if it was grinding between Snaresbrook and South Woodford too, as it was making a racket...or does it just sound like that when moving!?

 

[Dstock7080]

Wednesday night was 830m EB Leyton-Leytonstone
Thursday night was 450m WB Leyton-Stratford.