Mercedes-Benz first series automatic transmission
Mercedes-Benz K4A 025
K4B 050 · K4C 025 · K4A 040 W3A 040 · W3B 050 · W4B 025 W4A 018 · W4B 035 | |
---|---|
Overview | |
Manufacturer | Daimler AG |
Production | 1961–1983 |
Body and chassis | |
Class | 3 and 4-speed longitudinal automatic transmission |
Chronology | |
Successor | 4G-Tronic |
The Mercedes-Benz first series of automatic transmission was produced from 1961 to 1983 in four- and three-speed variants for Mercedes-Benz passenger cars. In addition, variants for commercial vehicles were offered.
This transmission was the first Mercedes-Benz automatic transmission in-house developing.[1] Before this, the company used semi-automatic systems like a vacuum-powered shifting for overdrive or the "Hydrak" hydraulic automatic clutch system. Alternatively, they bought automatic transmissions of other vendors, such as BorgWarner.
The automatic transmissions are for engines with longitudinal layout for rear-wheel-drive layout passenger cars. The control of the fully automatic system is fully hydraulic and it uses electrical wire only for the kickdown solenoid valve and the neutral safety switch.
Physically, it can be recognized for its pan which uses sixteen bolts.
1961: K4A 025
— 4-Speed Transmission With 2 Planetary Gearsets —
[edit]Layout
[edit]The K4A 025[a] (without type designation) is the first of the series, launched in April 1961 for the W111 220 SEb, later replaced with the more reliable K4C 025 (type 722.2). It is a 4-speed unit and uses fluid coupling (also referred in some manuals as hydraulic/automatic clutch).
The design of the transmission results in poor shifting comfort, which does not meet Mercedes-Benz standards. This applies in particular to the change from 2nd to 3rd gear (and vice versa), which requires a group change, i.e. affects all shift elements.
Specifications
[edit]For this first four-speed model[b] eight main components[c] are used. It is the only exemption which uses only two planetary gearsets for four speeds.
Gear Teeth and Ratios | Planetary Gearset Teeth Simple[e] |
Count | Total | Avg. | ||
---|---|---|---|---|---|---|
Model Type |
Version First Delivery |
[f] [g] |
[h] [i] |
Brakes Clutches |
Ratio Span |
Gear Step |
Gear | R | 1 | 2 | 3 | 4 | |
Step |
–R : 1 | 1 : 2 | 2 : 3 | 3 : 4 | ||
K4A 025 N/A |
25 kp⋅m (181 lb⋅ft) 1961[2][3] |
50 76 |
44 76 |
3 3 |
3.9789 | 1.5846 |
Ratio |
−4.1455 |
3.9789 |
2.5200 |
1.5789 |
1.0000 | |
Step | 1.0418 | 1.5789 | 1.5960 | 1.5789 | ||
Ratio |
- ^ Kupplungs-4-Gang-Automatik bis 25 kpm Eingangsdrehmoment
(clutch-4-gear-automatic with 25 kp⋅m (181 lb⋅ft) maximum input torque - ^ plus 1 reverse gear
- ^ 2 simple planetary gearsets, 3 brakes, 3 clutches
- ^ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage
- ^ Layout
(1) Planetary gearset 1 is on the input (turbine) side
(2) Output shaft is carrier 2 (the planetary gear carrier of gearset 2) - ^ Sun gear of gearset 1
- ^ Ring gear of gearset 1
- ^ Sun gear of gearset 2
- ^ Ring gear of gearset 2
1964: K4B 050 And Follow-Up Products
— 4-Speed Transmissions With 3 Planetary Gearsets —
[edit]Layout
[edit]The Mercedes-Benz 600 from April 1964, the first post-war "Grand Mercedes", is powered by the Mercedes-Benz M100 engine.This made a gearbox for the highest demands of luxury vehicles necessary. The design of the gearbox in the range was out of the question from the outset. The introduction of the 600 was therefore taken as an opportunity to develop a completely new design for the automatic transmission.
The first model with this new layout was the K4B 050 (without type designation). Beside the new layout the number of pinions is doubled from three to six to handle the much higher torque of the big block V8 engine.
After the satisfactory experience with the new design, it was adopted in 1967 for the new core model K4C 025 (Type 722.2) of the first automatic transmission series from Mercedes-Benz. With the small block V8 engine M 116, the K4A 040 (Type 722.2) was launched as a more powerful version of the same design.
When the torque converter technique was fully established, the fluid coupling was replaced by a torque converter for the smaller engines, which leads to the W4B 025 (type 722.1).[4] Used in L4, L5 and L6 engines due to its lower torque output. In normal situations, it rests stationary in 2nd gear, but it will use 1st gear when the vehicle starts moving and throttle is applied[5] or if L position is selected in gear selector.
The W4A 018 (type 720.1) was derived from the W4B 025 (type 722.1) for vans up to 5,600 kg (12,350 lb) and off road vehicles, the W4B 035 from the W4B 025 (type 722.1) and K4A 040 (type 722.2) for light trucks up to 13,000 kg (28,660 lb).[6] The main difference is the use of straight toothed planetary gearsets instead of skew toothed ones for better fuel efficiency at the price of lower noise comfort.
Specifications
[edit]For this second four-speed models[a] eight main components[b] are used.[4]
Gear Teeth and Ratios | Planetary Gearset Teeth Simple[d] |
Count | Total | Avg. | |||
---|---|---|---|---|---|---|---|
Simpson | Simple | ||||||
Model Type |
Version First Delivery |
[e] [f] |
[g] [h] |
[i] [j] |
Brakes Clutches |
Ratio Span |
Gear Step |
Gear | R | 1 | 2 | 3 | 4 | ||
Step |
–R : 1 | 1 : 2 | 2 : 3 | 3 : 4 | |||
K4B 050 N/A |
51 kp⋅m (369 lb⋅ft) 1964 |
50 76 |
44 76 |
44 76 |
3 2 |
3.9789 | 1.5846 |
Ratio |
−4.1455 |
3.9789 |
2.4589 |
1.5789 |
1.0000 | ||
Step | 1.0418 | 1.6182 | 1.5573 | 1.5789 | |||
K4C 025 722.2 |
25 kp⋅m (181 lb⋅ft) 1967[7] |
44 76 |
44 76 |
35 76 |
3 2 |
3.9833 | 1.5852 |
Ratio |
−5.4779 |
3.9833 |
2.3855 |
1.4605 |
1.0000 | ||
Step | 1.3752 | 1.6698 | 1.6333 | 1.4605 | |||
K4A 040 722.2 |
40 kp⋅m (289 lb⋅ft) 1969 |
44 76 |
44 76 |
35 76 |
3 2 |
3.9833 | 1.5852 |
Ratio | −5.4779 | 3.9833 | 2.3855 | 1.4605 | 1.0000 | ||
Step | 1.3752 | 1.6698 | 1.6333 | 1.4605 | |||
W4B 025 722.1 |
25 kp⋅m (181 lb⋅ft) 1972[7] |
44 76 |
44 76 |
35 76 |
3 2 |
3.9833 | 1.5852 |
Ratio | −5.4779 | 3.9833 | 2.3855 | 1.4605 | 1.0000 | ||
Step | 1.3752 | 1.6698 | 1.6333 | 1.4605 | |||
W4A 018[k] 720.1 |
18 kp⋅m (130 lb⋅ft) 1975 |
46 80 |
46 80 |
37 80 |
3 2 |
4.0060 | 1.5882 |
Ratio |
−5.4994 |
4.0060 |
2.3911 |
1.4625 |
1.0000 | ||
Step | 1.3728 | 1.6754 | 1.6349 | 1.4625 | |||
W4B 035[l] N/A |
35 kp⋅m (253 lb⋅ft) 1975 |
42 78 |
42 78 |
36 78 |
3 2 |
4.1758 | 1.6103 |
Ratio |
−5.8810 |
4.1758 |
2.4115 |
1.4615 |
1.0000 | ||
Step | 1.4083 | 1.7316 | 1.6500 | 1.4615 | |||
Ratio R & Even |
|||||||
Ratio Odd |
- ^ plus 1 reverse gear
- ^ 3 simple planetary gearsets, 3 brakes, 2 clutches
- ^ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage
- ^ Layout
(1) Planetary gearset 1 is on the input (turbine) side
(2) Output shaft is carrier 3 (the planetary gear carrier of gearset 3) - ^ Sun gear of gearset 1
- ^ Ring gear of gearset 1
- ^ Sun gear of gearset 2
- ^ Ring gear of gearset 2
- ^ Sun gear of gearset 3
- ^ Ring gear of gearset 3
- ^ for light duty trucks up to 5,600 kg (12,350 lb)[8][6]
- ^ for medium duty trucks up to 13,000 kg (28,660 lb)[6][9]
1971: W3A 040 And Follow-Up Products
— 3-Speed Transmissions With 2 Planetary Gearsets —
[edit]Layout
[edit]When the torque converter technique was fully established, three-speed units, the W3A 040 and W3B 050 (type 722.0) is combined with V8 engines, and it uses torque converter instead of fluid coupling.[1][4] The transmission saves one planetary gearset and uses the same housing as the four-speed versions. The free space therefore is used to reinforce the shift elements (brakes and clutches) to handle the higher torque of the V8 engines.
First the W3A 040 was released for the all new M117 V8 engine of the Mercedes-Benz W108 and W109 in 1971. The second in the series is the W3B 050, which was released initially for the W116 450 SE and SEL in 1973. At that time the four-speed transmission for the 350 SE and SEL was replaced by this three-speed model. The reinforced W3B 050 reinforced (type 722.003) is the strongest of the series, able to handle the input of the enlarged version of the Mercedes-Benz M100 engine, the biggest Mercedes-Benz engine in post-war history,[10] exclusively used in the W116 450 SEL 6.9.
Specifications
[edit]For the three-speed models[a] seven main components[b] are used, which shows economic equivalence with the direct competitor.
Gear Teeth and Ratios | Planetary Gearset Teeth Simple[d] |
Count | Total | Avg. | ||
---|---|---|---|---|---|---|
Model Type |
Version First Delivery |
[e] [f] |
[g] [h] |
Brakes Clutches |
Ratio Span |
Gear Step |
Gear | R | 1 | 2 | 3 | ||
Step |
–R : 1 | 1 : 2 | 2 : 3 | |||
W3A 040 722.0 |
40 kp⋅m (289 lb⋅ft) 1971[11] |
44 76 |
35 76 |
3 2 |
2.3061 | 1.5186 |
Ratio |
−1.8361 |
2.3061 |
1.4605 |
1.0000 | ||
Step | 0.7962 | 1.5789 | 1.4605 | |||
W3B 050 722.0 |
50 kp⋅m (362 lb⋅ft) 1973[11] |
44 76 |
35 76 |
3 2 |
2.3061 | 1.5186 |
Ratio | −1.8361 | 2.3061 | 1.4605 | 1.0000 | ||
Step | 0.7962 | 1.5789 | 1.4605 | |||
W3B 050 reinf. 722.0 |
56 kp⋅m (405 lb⋅ft) 1975[11] |
44 76 |
35 76 |
3 2 |
2.3061 | 1.5186 |
Ratio | −1.8361 | 2.3061 | 1.4605 | 1.0000 | ||
Step | 0.7962 | 1.5789 | 1.4605 | |||
Ratio |
- ^ plus 1 reverse gear
- ^ 2 simple planetary gearsets,[4] 3 brakes, 2 clutches
- ^ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage
- ^ Layout
(1) Planetary gearset 1 is on the input (turbine) side
(2) Output shaft is carrier 2 (the planetary gear carrier of gearset 2) - ^ Sun gear of gearset 1
- ^ Ring gear of gearset 1
- ^ Sun gear of gearset 2
- ^ Ring gear of gearset 2
Applications
[edit]K4C 025
[edit]Chassis code | Car model | Engine code | Transmission code |
---|---|---|---|
114.015 and 114.615 | 230.6 | 180.954 | 722.203 |
114.017 and 114.617 | 230.6 Lang | ||
114.011 and 114.611 | 250 | 130.923 | 722.204 |
114.023 and 114.623 | 250 C | ||
114.060 and 114.660 | 280 | 110.921 | 722.202 |
114.073 and 114.673 | 280 C | ||
114.062 and 114.662 | 280 E | 110.981 | 722.200 |
114.072 and 114.672 | 280 CE | ||
115.015 and 115.615 | 200 | 115.923 | 722.205 |
115.010 | 220 | 115.920 | |
115.115 and 115.715 | 200 D | 615.913 | 722.206 |
115.110 and 115.710 | 220 D | 615.912 | |
115.112 | 220 D Lang |
K4A 040
[edit]Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
109.057 | 300 SEL 3.5 | 3.5 L M 116 V8 |
722.201 | worldwide except USA |
108.067 | 280 SE 3.5 | |||
108.068 | 280 SEL 3.5 |
Chassis code | Car model | Engine code | Transmission code |
---|---|---|---|
107.043 | 350 SL | 116.982 (D-Jet) 116.984 (K-Jet) |
722.201 |
107.023 | 350 SLC |
W3A 040
[edit]Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
109.056 | 300 SEL 4.5 | 4.5 L M 117 V8 |
722.000 | USA only |
108.057 | 280 SE 4.5 | |||
108.058 | 280 SEL 4.5 |
Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
107.043 | 350 SL | 116.982 (D-Jet) 116.984 (K-Jet) |
722.002 | |
107.023 | 350 SLC | |||
107.044 | 450 SL | 117.982 (D-Jet) 117.985 (K-Jet) |
722.004 | USA and Japan only |
107.024 | 450 SLC |
Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
116.028 | 350 SE | 116.983 (D-Jet) 116.985 (K-Jet) |
722.002 | |
116.029 | 350 SEL | |||
116.032 | 450 SE | 117.983 (D-Jet) 117.986 (K-Jet) |
722.004 | USA and Japan only |
116.033 | 450 SEL |
W3B 050
[edit]Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
107.044 | 450 SL | 117.982 (D-Jet) 117.985 (K-Jet) |
722.004 | worldwide except USA and Japan |
107.024 | 450 SLC |
Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
116.032 | 450 SE | 117.983 (D-Jet) 117.986 (K-Jet) |
722.001 | worldwide except USA and Japan |
116.033 | 450 SEL | |||
116.036 | 450 SEL 6.9 | 100.985 | 722.003 | 722.003 W3B 050 reinforced[12] |
W4B 025
[edit]Chassis code | Car model | Engine code | Transmission code |
---|---|---|---|
107.042 | 280 SL | 110.982 · 110.986 · 110.990 | 722.103 · 722.112 |
107.022 | 280 SLC | 110.982 · 110.986 |
Chassis code | Car model | Engine code | Transmission code |
---|---|---|---|
114.015 and 114.615 | 230.6 | 180.954 | 722.105 |
114.017 and 114.617 | 230.6 Lang | ||
114.011 and 114.611 | 250 | 130.923 | 722.104 |
114.023 and 114.623 | 250 C | ||
114.060 and 114.660 | 280 | 110.921 | 722.102 |
114.073 and 114.673 | 280 C | ||
114.062 and 114.662 | 280 E | 110.981 | 722.103 |
114.072 and 114.672 | 280 CE | ||
115.015 and 115.615 | 200 | 115.923 | 722.106 |
115.017 | 230.4 | 115.951 | 722.110 |
115.115 and 115.715 | 200 D | 615.913 | 722.107 |
115.110 and 115.710 | 220 D | 615.912 | |
115.112 | 220 D Lang | ||
115.117 | 240 D | 616.916 | 722.108 |
115.119 | 240 D Lang | ||
115.114 | 240 D 3.0 | 617.910 | 722.109 |
Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
116.020 | 280 S | 110.922 | 722.100 · 722.102 · 722.111 | |
116.024 | 280 SE | 110.983 (D-Jet) 110.985 (K-Jet) |
722.101 · 722.103 · 722.112 | |
116.025 | 280 SEL | |||
116.120 | 300 SD | 617.950 | 722.120 | USA only |
Chassis code | Car model | Engine code | Transmission code |
Notes |
---|---|---|---|---|
123.020 | 200 | 115.938 · 115.939 | 722.115 | |
123.220 | 200 | 102.920 · 102.939 | 722.121 | |
123.280 | 200 T | |||
123.023 | 230 | 115.954 | 722.119 | |
123.083 | 230 T | |||
123.043 | 230 C | |||
123.223 | 230 E | 102.980 | 722.122 | |
123.283 | 230 TE | |||
123.243 | 230 CE | |||
123.026 | 250 | 123.920 · 123.921 | 722.113 | |
123.086 | 250 T | |||
123.028 | 250 Lang | |||
123.030 | 280 | 110.923 | 722.111 | |
123.050 | 280 C | |||
123.033 | 280 E | 110.984 · 110.988 | 722.112 | |
123.093 | 280 TE | |||
123.053 | 280 CE | |||
123.120 | 200 D | 615.940 | 722.116 | |
123.126 | 220 D | 615.941 | ||
123.123 | 240 D | 616.912 | 722.117 | |
123.183 | 240 TD | |||
123.125 | 240 D Lang | |||
123.130 | 300 D | 617.912 | 722.118 | |
123.190 | 300 TD | |||
123.132 | 300 D Lang | |||
123.150 | 300 CD | USA only |
See also
[edit]References
[edit]- ^ a b "50 years of automatic transmissions from Mercedes-Benz".
- ^ Johannes Looman · Zahnradgetriebe · pp. 133 ff · Berlin and Heidelberg 1970 · Print ISBN 978-3-540-04894-7
- ^ Ergebnis und Ausblick · Festschrift für Herrn Prof. Dr. Hans Joachim Förster zum Ausscheiden als Direktor aus dem aktiven Dienst der Daimler-Benz AG November 1982 (Result And Outlook · commemorative publication for Prof. Dr. Hans Joachim Foerster on the occasion of leaving as director from active duty at Daimler-Benz AG November 1982) · pp. 6 · 20
- ^ a b c d "MB Passenger Car Series 116, PDF p. 10" (PDF).
- ^ "MB Passenger Car Series 116, PDF p. 11" (PDF).
- ^ a b c Ergebnis und Ausblick · Festschrift für Herrn Prof. Dr. Hans Joachim Förster zum Ausscheiden als Direktor aus dem aktiven Dienst der Daimler-Benz AG November 1982 (Result And Outlook · commemorative publication for Prof. Dr. Hans Joachim Foerster on the occasion of leaving as director from active duty at Daimler-Benz AG November 1982) · pp. 9 · 22
- ^ a b Ergebnis und Ausblick · Festschrift für Herrn Prof. Dr. Hans Joachim Förster zum Ausscheiden als Direktor aus dem aktiven Dienst der Daimler-Benz AG November 1982 (Result And Outlook · commemorative publication for Prof. Dr. Hans Joachim Foerster on the occasion of leaving as director from active duty at Daimler-Benz AG November 1982) · pp. 7 · 20
- ^ Hans Joachim Foerster · Automatische Fahrzeuggetriebe · p. 487 · Berlin and Heidelberg 1991 · Print ISBN 978-3-642-84119-4 · Online ISBN 978-3-642-84118-7
- ^ Hans Joachim Foerster · Automatische Fahrzeuggetriebe · p. 489 · Berlin and Heidelberg 1991 · Print ISBN 978-3-642-84119-4 · Online ISBN 978-3-642-84118-7
- ^ Only surpassed by the Mercedes-Benz 770, built from 1930 to 1943
- ^ a b c Hans Joachim Foerster · Automatische Fahrzeuggetriebe · p. 452 · Berlin and Heidelberg 1991 · Print ISBN 978-3-642-84119-4 · Online ISBN 978-3-642-84118-7
- ^ "MB AUS 1979, PDF p. 57" (PDF).