Originally only eight sets were ordered by the BTC, this was changed to ten by the time B.U.T. ordered the power units from Leyland Motors Ltd in Nov. '58 (an order worth £86,000).
Initial allocations saw the LMR sets go to Newton Heath for northwest services and the WR cars were spread between the London area (55991/2), Tyseley (55993/4) for Midlands services and Chester (55995/6). Boundary changes in the mid-'60s saw Chester and Tyseley become part of the LMR, increasing that regions allocation.
Giving a useful shove up the hills to Buxton, a non-corridored Gloucester Parcels unit was marshalled at the rear of the 13:10 Piccadilly to Buxton (Stockport, 4/1/79). Paul Moxon.
In the '80s, some were allocated to the ER. At 1985 the five remaining sets in traffic were allocated to Reading (two), Newton Heath (two) and Chester (one). Typical duties of the Reading cars in '85 would be one set operating from Southall from Monday to Friday from 05:00 to 22:00. Duties in this time would include carrying letter-post, periodicals, parcels and Red Star traffic between Paddington and Reading and intermediate stations. the other set would act as a spare/relief unit.
Other duties for the class at this time included using them to convey staff from the WR to Stratford to collect WR sets. Newton Heath would also keep one as a spare, with the other working through Manchester Victoria to Manchester Mayfield Parcels Depot before being attached to a Buxton service set. this weekday working would return in the early evening to Piccadilly, then via Manchester Victoria to Newton Heath. Other workings in this area would have included Manchester to Oldham Mumps.
The Chester car had no booked diagram but would be used as required on special trains along the Cambrian Coast, and even worked ballast trains on the Barnmouth bridge due to locos being banned from crossing this during the '80s. 55994 worked a Crewe - Barnmouth special on the 17th June '80 for the then BR chairman Sir Peter Parker to inspect the bridge. During the 1984 Motor Show at the Birmingham NEC this car operated a special parcels service from Northampton to Birmingham, based at Nuneaton, although fuelled and serviced at Tyseley.
In 1988 the remaining cars were transferred to Cambridge.
Thought to be the only time a Class 128 has visited Skegness, in the late 1980's. 55993 was attached to an excursion train - for some reason it remained attached to the formation throughout the trip! Peter, Lincolnshire & East Yorkshire Transport Review.