Drove for Wimpey Lancaster Rd Southall Central Plant late 60s.One Morning a Driver Bob Trump got into his Cab an AEC Mercury Ergo Cab was filling in Log Book reving lightly when the Gearbox blue to bits and blew holes in the Cab Floor and Mudwings ,AEC said if i can remember right that the breather had got blocked and caused it.anybody ever came across anything like. Ben.