Abbreviations

This page is for any abbreviations used on site for specification, manufacturer codes and operators who incorporated code letters in their fleet numbers. It is constantly being updated, if you know of any codes that may be of interest to others or if you spot any errors please let me know it will be much appreciated.
You can contact me by email at obp-admin@nwframpton.com

Specification Codes
Body Layout
H	High-bridge double-deck (with centre gangways)
L	Low-bridge double-deck (with sunken side gangway upstairs)
B	Single-deck bus
C	Coach
DP	Dual-purpose single-deck
F	Full front, where not usually fitted
O	Open top
U	Utilility (wartime) type body
BB	Beverley Bar roof as supplied to East Yorkshire Motor Services
Entrance (shown after seating capacity if split upper deck shown first)
R	Rear entrance
RD	Rear entrance fitted with doors
F	Front entrance
C	Centre entrance
D	Dual entrance
AEC vehicle chassis codes
Bridgemaster codes 1956-1963
Prefix code
B	rear entrance
2B	front entrance
Centre code number
3	Clutch four speed synchromesh gearbox
Suffix code
R	Right hand drive
L	Left hand drive
A	Air pressure brakes
Regal IV codes 1949-1953
9821E	1949-50, 27ft 6in long, AEC A219 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes, only 25 built and all to London Transport
9821E	1950-53, 30ft long, AEC A219 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes, London Transport only had this version
9831E	As 9821E above but left hand drive
9821S	1952, 30ft long, AEC A219 9.6 litre six cylinder diesel, four speed synchromesh gearbox, air pressure brakes, not many built
9822E	1952-53, 30ft long, increased frame height, AEC A219 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes
9822S	1952-53, 30ft long, increased frame height, AEC A219 9.6 litre six cylinder diesel, four speed synchromesh gearbox, air pressure brakes
Regent III codes 1947-1956
O681	1947-48, 26ft long, AEC A173 7.7 litre six cylinder diesel, four speed crash gearbox, vacuum assisted brakes
6811A	1948-50, 26ft long, AEC A173 7.7 litre six cylinder diesel, four speed crash gearbox, vacuum brakes
6812A	1950-56, 27ft long, AEC A173 7.7 litre six cylinder diesel, four speed crash gearbox, vacuum assisted brakes
6813S	1950-56, 27ft long, AEC A173 7.7 litre six cylinder diesel, four speed synchromesh gearbox, vacuum assisted brakes
O961/2	1947-48, 26ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes
9612E	1948-50, 26ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes
9613E	1950-56, 27ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed air operated preselective gearbox, air pressure brakes
SV179	1947-48, 26ft long, AEC A173 7.7 litre six cylinder diesel, four speed crash gearbox, vacuum assisted brakes
9612A	1948-50, 26ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed crash gearbox, vacuum assisted brakes
9613A	1950-56, 27ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed crash gearbox, vacuum assisted brakes
9613S	1950-56, 27ft long, AEC A208 or 218 9.6 litre six cylinder diesel, four speed synchromesh gearbox, vacuum assisted brakes
Regent V codes 1954-1969
Prefix code
D	27 foot long with AEC A218 or AV590 9.6 litre six cylinder diesel
2D	(series 2) 27 or 30 foot long with AEC AV590 9.6 litre six cylinder diesel
MD	(medium weight) 27 foot long with AEC AV470 7.68 litre six cylinder diesel
LD	30 foot long with AEC A218 or AV590 9.6 litre six cylinder diesel
Centre code numbers
2	Monocontrol four speed direct selection epicyclic gearbox
3	Clutch four speed synchromesh gearbox
Suffix code
R	Right hand drive
L	Left hand drive
A	Air pressure brakes
V	Vacuum assisted brakes
One offs
D2RV6G / D2RA6G	27 foot long with Gardner 6LW 8.4 litre six cylinder diesel
Reliance Codes contributed by David Oldfield
Reliance Medium Weight codes with one of the following (AH410/AH470/AH505) engines
–	Version Numbers	Earliest versions had no number ie MU3RV – AH410 or AH470
2		Most numerous versions 2MU3RV and 2MU3RA – AH410 or AH470
4		Version 4 was 36 foot long – AH470
6		Version 6 had the – AH505
M	Medium weight	If missing denotes it is the Heavy Weight Reliance
U	Underfloor engine
2	Monocontrol gearbox
3	Synchromesh gearbox
4	Constant mesh gearbox
R	Right hand drive
L	Left hand drive
A	Air brakes
V	Vacuum brakes
Reliance Heavy Weight codes with one of the following (AH590/AH691/AH760) engines
2	Original version	AH590 engine
4	Air suspension version
6	version	AH691 and subsequently AH760 engine
8	Coil-Spring suspension version
9	12m version
U
Underfloor engine
2	Monocontrol gearbox
3	Synchromesh gearbox
Z	6 speed ZF gearbox
R	Right hand drive
L	Left hand drive
A	Air brakes
The above were eventually all standardised in the 6U3ZR whatever length and suspension.
Renown codes 1962-1967
Prefix code
3B	30 foot long with AEC AV590 9.6 litre six cylinder diesel
Centre code numbers
2	Monocontrol four speed direct selection epicyclic gearbox
3	Clutch four speed synchromesh gearbox
Suffix code
R	Right hand drive
L	Left hand drive
A	Air pressure brakes
Routemaster codes 1954-1967
R2RH	1954-65, 27ft 6in long, AV590 9.6 litre six cylinder diesel, four speed fully automatic or direct selection epicyclic gearbox, hydraulic brakes
R2RH/1	1961-67, 30ft long, AV590 9.6 litre six cylinder diesel, four speed fully automatic or direct selection epicyclic gearbox, hydraulic brakes
2R2RH	1954-65, 27ft 6in long, Leyland O600 9.8 litre six cylinder diesel, four speed fully automatic or direct selection epicyclic gearbox, hydraulic brakes
3R2RH	1964-65, front entrance, 30ft long, AV590 9.6 litre six cylinder diesel, four speed fully automatic or direct selection epicyclic gearbox, hydraulic brakes
Bristol vehicle chassis codes
Prefix code
Single Deckers
L series 1938-1954
L	L series 26′ x 7’6″ front vertical engined bus, coach or dual purpose
LW	L series wide 26′ x 8’0″ front vertical engined bus, coach or dual purpose
LL	L series long 30′ x 7’6″ front vertical engined bus, coach or dual purpose
LWL	L series wide long 30′ x 8’0″ front vertical engined bus, coach or dual purpose
LS	1951-1958 light saloon 30′ x 8’0″ underfloor engined bus, coach or dual purpose
SC	1954-1961 small capacity bus 27’6″ x 7’6″, coach 26’6″ x 7’6″ front vertical engine bus or coach
MW	1957-1967 medium weight 30′ x 8’0″ underfloor engined bus, coach or dual purpose. The MW was bodied to 31′ x 8′ for coaches from 1963 onwards (although the chassis remained the same) but it is body sizes, rather than chassis sizes quoted elsewhere in the lists.
SU series 1960-1966
SUS	small underfloor short 24’2″ x 7’6″ underfloor engined bus
SUL	small underfloor long bus 27’10” x 7’6″, coach 28’2″ x 7’6″ underfloor engine bus or coach
RELL	rear engined long length low floor 36′ x 8’0″ rear engined bus
RELH	rear engined long length high floor 36′ x 8’0″ rear engined coach
REMH	rear engined motorway high floor 39’4″ x 8’0″ rear engined coach
RESL	rear engined short length low floor 32’6″ x 8’0″ rear engined bus
RESH	rear engined short length high floor 32’6″ x 8’0″ rear engined coach
Double Deckers
K series 1937-1950
K	K series’ 26′ x 7’6″
KW	K series wide 26′ x 8’0″
KS series 1950-1957
KS	KS series’ 27′ x 7’6″
KSW	KS series wide 27′ x 8’0″
Lodekka LD series 1953-1959
LD	Lodekka sunken gangway on the lower deck 27′ x 8’0″
LDL	Lodekka – long sunken gangway on the lower deck 30′ x 8’0″
Lodekka FS series 1959-1968
FS	Lodekka – flat floor on the lower deck – short length – rear entrance’ 27′ x 8’0″
FL	Lodekka – flat floor on the lower deck – long length – rear entrance’ 30′ x 8’0″
FSF	Lodekka – flat floor on the lower deck – short length – front entrance’ 27′ x 8’0″
FLF	Lodekka – flat floor on the lower deck – long length – front entrance’ 30′ x 8’0″
VR series 1968-1981
VRL/LH	– vertical rear longitudinal engined long length high floor 36′ x 8’0″
VRT/LL	– vertical rear transverse engined long length low floor 33′ x 8’0″
VRT/SL	– vertical rear transverse engined short length low floor 30′ x 8’0″
VRT/LH	– vertical rear transverse engined long length high floor 33′ x 8’0″
Suffix code
4A	Albion EN250H – 4.1 litre, four cylinder diesel
4LK	Gardner 4LK, 3.8 litres, four cylinder diesel
4G	Gardner 4LW, 5.6 litres, four cylinder diesel
5G	Gardner 5LW, 7.0 litres, five cylinder diesel
6G	Gardner 6LW, 8.4 litres, (or 6LX 10.45 litres) six cylinder diesel
6LX	Gardner 10.45 litres, six cylinder diesel
6A	AEC A202, 7.7 litres, six cylinder diesel
6B	Bristol AW, 8.14 litres or BWV, 8.9 litre, six cylinder diesel
6L	Leyland O.600 9.8 litres or (less common) O.510 8.2 litres, six cylinder diesel; or O.680 11.1 litres
Daimler vehicle chassis codes
First code letter
C	Commercial
Second Code letter
F	Series Version
H	Series Version
P	Petrol
O	Oil 1934-1940
W	War 1943-1947
V	Victory 1946-1967 UK/1972 OS
S	Synchromesh gearbox
C	Constant mesh gearbox
L	Lightweight
R	Rear engine
RE	Rear engine (early code for Fleetline)
Third code letter (engine code)
D	Daimler 8.6 litres, six cylinder diesel
G	Gardner 5LW, 7.0 litres, five cylinder diesel or 6LW, 8.4 litres, six cylinder diesel
A	AEC A173 7.7 litre six cylinder diesel
L	Leyland
Fourth code number
5	5 cylinder engine
6	6 cylinder engine
6LW	8.4 litre Gardner engine (suffix for the Fleetline only)
6LX	10.5 litre Gardner engine (suffix for the Fleetline only)
Fifth code number (length in Feet and not always used)
27	feet
30	feet
33	feet
36	feet
Sixth code letters (for CV only that I can see and not always used)
DD	Double Decker
Special Codes
There was a one off CD-650 chassis but the code was really for the 10.6 litre six cylinder engine
COG5/40 single deck chassis which seated 39 passengers
COG5/60 double deck chassis for Coventry Corporation which seated 60 passengers
Dennis Loline III vehicle chassis codes
L3	Loline III
A	Long Wheelbase
B	reserved for 27ft 6in length, but none were made
C	for the shorter length Reading buses
F	Forward Entrance
1	Gardner 6LW engine
2	Gardner 6LX
3	Leyland O.600
A	Dennis 5 speed gearbox for 6LW
B	Dennis 5 speed for 6LX
C	Dennis 4 speed for 6LW and similarly rated engines
D	Dennis 4 speed for 6LX
E	SCG 4 speed (for Belfast, China Bus and Dennis demonstrator examples)
F	SCG 5 speed (for Halifax)
G	Bristol 5 speed (for Reading)
1	Dennis rear axle
2	Bristol rear axle
Leyland Titan PD vehicle chassis codes
All PD1s had the Leyland E181 7.4 litre six cylinder diesel engine
PD1	26′ x 7’6″ – exposed radiator – constant-mesh gearbox – vacuum brakes – 1946/50
PD1/A	26′ x 7’6″ – exposed radiator – constant-mesh gearbox – vacuum brakes – 1946/50
– slight suspension alteration
PD1/3	26′ x 8’0″ – exposed radiator – constant-mesh gearbox – vacuum brakes – 1946/50
All PD2s had the Leyland O.600 9.8 litre six cylinder diesel engine
PD2/1	26′ x 7’6″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1947/50
PD2/3	26′ x 8’0″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1947/50
PD2/4	26′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1947/50
PD2/5	26′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1949/51
Special version for Blackpool full fronted centre entrance.
PD2/10	27′ x 7’6″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1950/55
PD2/11	27′ x 7’6″ – exposed radiator – pneumocyclic gearbox – air brakes – 1950/55
PD2/12	27′ x 8’0″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1950/55
PD2/13	27′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1950/55
PD2/14	27′ x 7’6″ – exposed radiator – preselective gearbox – air brakes – 1950/55
PD2/20	27′ x 8’0″ – concealed radiator – synchromesh gearbox – vacuum brakes – 1953/55
PD2/21	27′ x 8’0″ – concealed radiator – synchromesh gearbox – air brakes – 1953/55
PD2/22	27′ x 7’6″ – concealed radiator – synchromesh gearbox – vacuum brakes – 1953/55
PD2/23	27′ x 7’6″ – concealed radiator – synchromesh gearbox – air brakes – 1953/55
PD2/24	27′ x 8’0″ – concealed radiator – direct selection epicyclic gearbox – air brakes – 1954/68
PD2/25	27′ x 7’6″ – concealed radiator – direct selection epicyclic gearbox – air brakes – 1954/62
PD2/26	27′ x 8’0″ – concealed radiator – direct selection epicyclic gearbox – air brakes – 1954/68
A Lightweight version.
PD2/27	27′ x 8’0″ – concealed radiator – synchromesh gearbox – air brakes – 1955/68
PD2/28	27′ x 7’6″ – concealed radiator – synchromesh gearbox – air brakes – 1955/62
PD2/30	27′ x 8’0″ – concealed radiator – synchromesh gearbox – vacuum brakes – 1955/68
PD2/31	27′ x 7’6″ – concealed radiator – synchromesh gearbox – vacuum brakes – 1955/62
PD2/34	27′ x 8’0″ – exposed radiator – direct selection epicyclic gearbox – air brakes – 1955/68
PD2/35	27′ x 7’6″ – exposed radiator – direct selection epicyclic gearbox – air brakes – 1955/62
PD2/37	27′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1955/68
PD2/38	27′ x 7’6″ – exposed radiator – synchromesh gearbox – air brakes – 1955/62
PD2/40	27′ x 8’0″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1950/68
PD2/41	27′ x 7’6″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1955/62
All PD3s had the Leyland O.600 9.8 litre six cylinder diesel engine
PD3/1	30′ x 8’0″ – concealed radiator – synchromesh gearbox – air brakes – 1955/69
PD3/2	30′ x 8’0″ – concealed radiator – direct selection epicyclic gearbox – air brakes – 1955/67
PD3/3	30′ x 8’0″ – concealed radiator – synchromesh gearbox – vacuum brakes – 1955/62
PD3/4	30′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1955/69
PD3/5	30′ x 8’0″ – exposed radiator – direct selection epicyclic gearbox – air brakes – 1955/67
PD3/6	30′ x 8’0″ – exposed radiator – synchromesh gearbox – vacuum brakes – 1955/67
PD3/11	30′ x 8’0″ – concealed radiator – synchromesh gearbox – air brakes – 1967/69
PD3/12	30′ x 8’0″ – concealed radiator – direct selection epicyclic gearbox – air brakes – 1967/69
PD3/14	30′ x 8’0″ – exposed radiator – synchromesh gearbox – air brakes – 1967/69
PD3/15	30′ x 8’0″ – exposed radiator – direct selection epicyclic gearbox – air brakes – 1967/69
Concealed radiators
In 1960 the style of the concealed radiator changed from the vertically slatted grilled – ‘Tin Front’ version based on the BMMO D7 design. The new – Scalloped’ version with horizontally slatted grill was mainly made of glass fibre. The new front resulted in a suffix code of a letter – ‘A’ being added to the basic model number eg PD3A/1.
Operator Fleet List Codes
United Automobile Services codes
B	Single deck Bristol L or LL type bus with Bristol 6 cylinder engine
G	Single deck Bristol L or LL type bus with Gardner 5 cylinder engine
U	Single deck Bristol LS or MW type bus with 5 or 6 cylinder Gardner engines
R	Single deck Bristol RELL type with Gardner 6 cylinder engine
GS	Single deck Bristol LL type bus with Gardner 5 cylinder engine (Scarborough seafront service)
S	Single deck Bristol SUL type bus with a 4 cylinder Albion engine
BBL	Double deck Bristol K or KSW type with a lowbridge body and Bristol 6 cylinder engine
GL	Double deck Bristol K type with a lowbridge body and Gardner 5 cylinder engine
BH	Double deck Bristol K, KS and KSW type with a highbridge body and Bristol 6 cylinder engine
L	Double deck Bristol Loddeka Gardner or Bristol engine
UE	Single deck Bristol LS & MW type dual purpose body with Bristol or Gardner engine
UT	Single deck Bristol LS type coach body with Bristol engine
UC	Single deck Bristol LS & MW type coach body with Bristol or Gardner engine
RE	Single deck Bristol RELL type coach body with Gardner engine
LUT	Single deck Leyland Royal Tiger type coach body with Leyland engine
West Yorkshire (Road Car Company) codes
SG	Single deck Bristol L type bus with Gardner engine
SGL	Single deck Bristol LL type bus 30ft long with Gardner engine
SGW	Single deck Bristol LL & LWL type bus 30ft long with Gardner engine & 8ft wide body
SB	Single deck Bristol L type bus with Bristol engine
SBW	Single deck Bristol LL & LWL type bus 30ft long with Bristol engine & 8ft wide body
EBW	Single deck Bristol LWL type dual purpose body with Bristol engine
EUG	Single deck Bristol LS & MW type dual purpose body with Gardner engine
SUG	Single deck Bristol LS type bus converted from a dual purpose body with Gardner engine
SMA	(Saloon Medium Albion) Single deck Bristol SU type bus with Albion engine
SMP	(Saloon Medium Perkins) Single deck Bristol SU type bus with Perkins engine
CUG	Bristol LS & MW type coach with Gardner engine
CP	Bedford coach with Petrol engine
SP	Bedford bus with Petrol engine
DG	Double deck Bristol K type with Gardner engine
DB	Double deck Bristol K & KS type with Bristol engine
DBW	Double deck Bristol KSW type 8ft wide with Bristol engine
DGW	Double deck Bristol KSW type 8ft wide with Gardner engine
DX	Double deck Bristol Loddeka Gardner or Bristol engine
K	Preceding above codes denotes Keighley West Yorkshire
Y	Preceding above codes denotes York West Yorkshire