(19 Aug 2025, 11:01 am)L469 YVK wrote Asides from the X10 which even 6043-48 had trouble doing, got to be engineering related considering in context that Ashington and Redcar seem to keep their MMCs on the road doing much harder worm even if patchy at times.

And even though GNE's are ZF instead of Voith, Arriva's late registered ZF classics didn't give too bad of a service on the Ashington & Alnwick work

Personally, I'd take a Voith over a ZF these days. The ZFs fitted to Arriva's E400s, particularly the ones in 7514-21, are horrific - which is widely reported. Change up too early, reliability issues, clunky changes. In my time driving, I covered far more distance in Voith vehicles yet each time I had a gearbox completely give up it was a ZF E400. 

On the other hand, the Voith-equipped MMCs are generally smoother and appear to be more reliable. 

Volvo products with ZFs were a different situation entirely though, very good.