1980: Simpson Planetary Gearset Types The 4HP  20  was introduced in 1995 and has been used in a variety of cars from Citroën , Lancia , Mercedes-Benz , Peugeot , and Renault . [ 1]     The maximum torque capacity is 330    N⋅m   (243    lb⋅ft  ) .
The 4HP  22  was produced for vehicles with rear wheel drive  or 4X4  layout. Introduced in 1980, it was produced through 2003, and has been used in a variety of cars from BMW , General Motors , Jaguar , Land Rover , Maserati , Peugeot , Porsche , and Volvo .
The 4HP  24  was introduced in 1987 and was used in a variety of cars from Audi , BMW , Jaguar , and Land Rover .
Gear  Ratios With Assessment Planetary Gearset: Teeth [ a]     Count Total [ b]     Center [ c]     Avg. [ d]      Simpson    Simple   Model Type Version First Delivery S1  [ e]     R1  [ f]     S2  [ g]     R2  [ h]     S3  [ i]     R3  [ j]     Brakes Clutches Ratio Span Gear Step [ k]     Gear Ratio Ri R {\displaystyle {i_{R}}}  1i 1 {\displaystyle {i_{1}}}  2i 2 {\displaystyle {i_{2}}}  3i 3 {\displaystyle {i_{3}}}  4i 4 {\displaystyle {i_{4}}}  Step [ k]     − i R i 1 {\displaystyle -{\tfrac {i_{R}}{i_{1}}}}  [ l]    i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{1}}}} i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{2}}}}  [ m]    i 2 i 3 {\displaystyle {\tfrac {i_{2}}{i_{3}}}} i 3 i 4 {\displaystyle {\tfrac {i_{3}}{i_{4}}}} Δ  Step [ n]     [ o]     i 1 i 2 : i 2 i 3 {\displaystyle {\tfrac {i_{1}}{i_{2}}}:{\tfrac {i_{2}}{i_{3}}}} i 2 i 3 : i 3 i 4 {\displaystyle {\tfrac {i_{2}}{i_{3}}}:{\tfrac {i_{3}}{i_{4}}}} Shaft Speed i 1 i R {\displaystyle {\tfrac {i_{1}}{i_{R}}}} i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{1}}}} i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{2}}}} i 1 i 3 {\displaystyle {\tfrac {i_{1}}{i_{3}}}} i 1 i 4 {\displaystyle {\tfrac {i_{1}}{i_{4}}}} Δ Shaft Speed [ p]     0 − i 1 i R {\displaystyle 0-{\tfrac {i_{1}}{i_{R}}}} i 1 i 1 − 0 {\displaystyle {\tfrac {i_{1}}{i_{1}}}-0} i 1 i 2 − i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{2}}}-{\tfrac {i_{1}}{i_{1}}}} i 1 i 3 − i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{3}}}-{\tfrac {i_{1}}{i_{2}}}} i 1 i 4 − i 1 i 3 {\displaystyle {\tfrac {i_{1}}{i_{4}}}-{\tfrac {i_{1}}{i_{3}}}} 4HP  22 Large Engines 380    N⋅m   (280    lb⋅ft  )  198035 73 35 73 31 83 4 3 3.4055 1.3436 1.5045  [ k]    Gear Ratio −2.0857 [ l]    − 73 35 {\displaystyle -{\tfrac {73}{35}}}  2.4795 181 73 {\displaystyle {\tfrac {181}{73}}} 1.4795 [ m]    108 73 {\displaystyle {\tfrac {108}{73}}}  1.0000 1 1 {\displaystyle {\tfrac {1}{1}}} 0.7281 83 114 {\displaystyle {\tfrac {83}{114}}} Step 0.8412  [ l]    1.0000 1.6759  [ m]    1.4795 1.3735 Δ  Step [ n]     1.1328 1.0771 Speed -1.1888 1.0000 1.6759 2.4795 3.4055 Δ Speed 1.1888 1.0000 0.6759 0.8035 0.9261 4HP  22 Small Engines 220    N⋅m   (162    lb⋅ft  )  198035 73 41 73 31 83 4 3 3.7539 1.4106 1.5541  [ k]    Gear Ratio −2.0857  [ l]    − 73 35 {\displaystyle -{\tfrac {73}{35}}} 2.7331 6 , 983 2 , 555 {\displaystyle {\tfrac {6,983}{2,555}}} 1.5616  [ m]     [ o]    114 73 {\displaystyle {\tfrac {114}{73}}} 1.0000  [ k]    1 1 {\displaystyle {\tfrac {1}{1}}} 0.7281 83 114 {\displaystyle {\tfrac {83}{114}}} Step 0.7631  [ l]    1.0000 1.7501  [ m]    1.5616  [ k]    1.3735 Δ  Step [ n]     1.1207  [ o]    1.1370 Speed -1.3104 1.0000 1.7501 2.7331 3.7539 Δ Speed 1.3104 1.0000 0.7501 0.9829 1.0208 Ratio − R 1 S 1 {\displaystyle -{\tfrac {R_{1}}{S_{1}}}} S 1 ( S 2 + R 2 ) + R 1 S 2 S 1 R 2 {\displaystyle {\tfrac {S_{1}(S_{2}+R_{2})+R_{1}S_{2}}{S_{1}R_{2}}}} S 2 + R 2 R 2 {\displaystyle {\tfrac {S_{2}+R_{2}}{R_{2}}}} 1 1 {\displaystyle {\tfrac {1}{1}}} R 3 S 3 + R 3 {\displaystyle {\tfrac {R_{3}}{S_{3}+R_{3}}}} Algebra And Actuated Shift Elements Brake A [ q]     ❶ Brake B [ r]     ❶ ❶ Brake C [ s]     ❶ ❶ ❶ Brake S [ t]     ❶ Clutch E [ u]     ❶ ❶ ❶ ❶ Clutch F [ v]     ❶ ❶ ❶ Clutch S [ w]     ❶ ❶ ❶ ❶  ↑     Layout Input and output are on opposite sides Planetary gearset 1 is on the input (turbine) side Input shafts is, if actuated S1   or  R2   Output shaft is R3    ↑     Total Ratio Span (Total Ratio Spread · Total Gear Ratio) i 1 i n {\displaystyle {\tfrac {i_{1}}{i_{n}}}} A wider span enables the downspeeding when driving outside the city limits increase the climbing ability when driving over mountain passes or off-road or when towing a trailer    ↑     Ratio Span's Center ( i 1 i n ) 1 2 {\displaystyle (i_{1}i_{n})^{\tfrac {1}{2}}} The center indicates the speed level of the transmission Together with the final drive ratio it gives the shaft speed level of the vehicle  ↑     Average Gear Step ( i 1 i n ) 1 n − 1 {\displaystyle ({\tfrac {i_{1}}{i_{n}}})^{\tfrac {1}{n-1}}} With decreasing step width the gears connect better to each other shifting comfort increases   ↑     Sun 1: sun gear of gearset 1  ↑     Ring 1: ring gear of gearset 1  ↑     Sun 2: sun gear of gearset 2  ↑     Ring 2: ring gear of gearset 2  ↑     Sun 3: sun gear of gearset 3  ↑     Ring 3: ring gear of gearset 3  1    2    3    4    5    6     Standard  50:50—   50  % Is Above And 50  % Is Below The Average Gear Step  —  With steadily decreasing gear steps (yellow highlighted line Step ) and a particularly large step from 1st to 2nd gear the lower half of the gear steps  (between the small gears; rounded down, here the first 1) is always larger  and the upper half of the gear steps  (between the large gears; rounded up, here the last 2) is always smaller   than the average gear step  (cell highlighted yellow two rows above on the far right)lower half: smaller gear steps are a waste of possible ratios (red  bold)  upper half: larger gear steps are unsatisfactory (red  bold)   1    2    3    4    5     Standard  R:1—   Reverse And 1st Gear Have The Same Ratio  —  The ideal reverse gear has the same transmission ratio as 1st gear no impairment when maneuvering especially when towing a trailer a torque converter can only partially compensate for this deficiency  Plus 11.11  % minus 10  % compared to 1st gear is good Plus 25  % minus 20  % is acceptable (red) Above this is unsatisfactory (bold)  1    2    3    4    5     Standard  1:2—   Gear Step 1st To 2nd Gear As Small As Possible  —  With continuously decreasing gear steps (yellow marked line Step ) the largest gear step is the one from 1st to 2nd gear,  which for a good speed connection and a smooth gear shift  must be as small as possible A gear ratio of up to 1.6667:1 (5:3) is good Up to 1.7500:1 (7:4) is acceptable (red) Above is unsatisfactory (bold)   1    2    3     From large to small gears (from right to left)  1    2    3     Standard  STEP—   From Large To Small Gears: Steady And Progressive Increase In Gear Steps  —  Gear steps should increase:  Δ  Step (first green highlighted line Δ  Step ) is always greater than 1As progressive  as possible: Δ  Step is always greater than the previous step  Not progressively increasing is acceptable (red) Not increasing is unsatisfactory (bold)  ↑     Standard  SPEED—   From Small To Large Gears: Steady Increase In Shaft Speed Difference  —  Shaft speed differences should increase:  Δ  Shaft Speed (second line marked in green Δ  (Shaft) Speed ) is always greater than the previous one 1 difference smaller than the previous one is acceptable (red) 2 consecutive ones are a waste of possible ratios (bold)  ↑     Blocks S1    ↑     Blocks C1   (the carrier of gearset 1)  ↑     Blocks S2    ↑     Blocks S3   (S: german "schnell" for fast)  ↑     Couples R2   with the turbine  ↑     Couples S1   with the turbine  ↑     Couples S3   with C3   (the carrier of gearset 3 · S: german "schnell" for fast) 
1984: Ravigneaux Planetary Gearset Types The 4HP  14  was introduced in 1984 and produced through 2001 for Citroën , Peugeot , and Daewoo  Front-wheel drive  vehicles. The electronic-hydraulic control makes controlled power shifts and various shift programs possible.
The 4HP  16  is designed for use in vehicles with Front-wheel drive  and a Transverse engine . The transmission is operated via selector lever and possibly also via switch. It has a controller slip Lock-up clutch .
The 4HP  18  is for both longitudinal and transverse installation. Introduced in 1987, and produced through 1998, it was used in a variety of cars from Alfa Romeo , Audi , Citroën , Dodge , Eagle , Fiat , Lancia , Porsche  and Saab .
Gear  Ratios With Assessment Planetary Gearset: Teeth [ a]     Count Total [ b]     Center [ c]     Avg. [ d]     Model Type Version First Delivery S1  [ e]     R1  [ f]     S2  [ g]     R2  [ h]     Brakes Clutches Ratio Span Gear Step [ i]     Gear Ratio Ri R {\displaystyle {i_{R}}}  1i 1 {\displaystyle {i_{1}}}  2i 2 {\displaystyle {i_{2}}}  3i 3 {\displaystyle {i_{3}}}  4i 4 {\displaystyle {i_{4}}}  Step [ i]     − i R i 1 {\displaystyle -{\tfrac {i_{R}}{i_{1}}}}  [ j]    i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{1}}}} i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{2}}}}  [ k]    i 2 i 3 {\displaystyle {\tfrac {i_{2}}{i_{3}}}} i 3 i 4 {\displaystyle {\tfrac {i_{3}}{i_{4}}}} Δ  Step [ l]     [ m]     i 1 i 2 : i 2 i 3 {\displaystyle {\tfrac {i_{1}}{i_{2}}}:{\tfrac {i_{2}}{i_{3}}}} i 2 i 3 : i 3 i 4 {\displaystyle {\tfrac {i_{2}}{i_{3}}}:{\tfrac {i_{3}}{i_{4}}}} Shaft Speed i 1 i R {\displaystyle {\tfrac {i_{1}}{i_{R}}}} i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{1}}}} i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{2}}}} i 1 i 3 {\displaystyle {\tfrac {i_{1}}{i_{3}}}} i 1 i 4 {\displaystyle {\tfrac {i_{1}}{i_{4}}}} Δ Shaft Speed [ n]     0 − i 1 i R {\displaystyle 0-{\tfrac {i_{1}}{i_{R}}}} i 1 i 1 − 0 {\displaystyle {\tfrac {i_{1}}{i_{1}}}-0} i 1 i 2 − i 1 i 1 {\displaystyle {\tfrac {i_{1}}{i_{2}}}-{\tfrac {i_{1}}{i_{1}}}} i 1 i 3 − i 1 i 2 {\displaystyle {\tfrac {i_{1}}{i_{3}}}-{\tfrac {i_{1}}{i_{2}}}} i 1 i 4 − i 1 i 3 {\displaystyle {\tfrac {i_{1}}{i_{4}}}-{\tfrac {i_{1}}{i_{3}}}} 4HP  14 1984 3429  [ o]     29  822 3 3.2647 1.3348 1.4835  [ i]    Gear Ratio −2.8276 [ j]    − 82 29 {\displaystyle -{\tfrac {82}{29}}}  2.4118 41 17 {\displaystyle {\tfrac {41}{17}}} 1.3688  [ k]    861 629 {\displaystyle {\tfrac {861}{629}}} 1.0000 [ n]    1 1 {\displaystyle {\tfrac {1}{1}}}  0.7281 82 111 {\displaystyle {\tfrac {82}{111}}} Step 1.1724  [ j]    1.0000 1.7619  [ k]    1.3688 1.3537 Δ  Step [ l]     1.2872 1.0112 Speed -0.8529 1.0000 1.7619 2.4118 3.2647 Δ Speed 0.8529 1.0000 0.7619 0.6499  [ n]    0.8526 4HP  18 FLE 1991 3834  [ o]     34  982 3 3.4737 1.3837 1.5145  [ i]    Gear Ratio −2.8824 [ j]    − 49 17 {\displaystyle -{\tfrac {49}{17}}}  2.5789 49 19 {\displaystyle {\tfrac {49}{19}}} 1.4067  [ k]    294 209 {\displaystyle {\tfrac {294}{209}}} 1.0000 [ n]    1 1 {\displaystyle {\tfrac {1}{1}}}  0.7281 49 66 {\displaystyle {\tfrac {49}{66}}} Step 1.1176  [ j]    1.0000 1.8333  [ k]    1.4067 1.3469 Δ  Step [ l]     1.3033 1.0444 Speed -0.8947 1.0000 1.8333 2.5789 3.4737 Δ Speed 0.8947 1.0000 0.8333 0.7456  [ n]    0.8947 Ratio − R 2 S 2 {\displaystyle -{\tfrac {R_{2}}{S_{2}}}} R 1 R 2 S 1 S 2 {\displaystyle {\tfrac {R_{1}R_{2}}{S_{1}S_{2}}}} R 2 ( S 1 + R 1 ) S 1 ( S 2 + R 2 ) {\displaystyle {\tfrac {R_{2}(S_{1}+R_{1})}{S_{1}(S_{2}+R_{2})}}} 1 1 {\displaystyle {\tfrac {1}{1}}} R 2 S 2 + R 2 {\displaystyle {\tfrac {R_{2}}{S_{2}+R_{2}}}} Algebra And Actuated Shift Elements Brake A [ p]     ❶ ❶ Brake B [ q]     ❶ ❶ Clutch C [ r]     ❶ ❶ ❶ Clutch D [ s]     ❶ Clutch E [ t]     ❶ ❶  ↑     Layout Input and output are on opposite sides Planetary gearset 2 (the outer Ravigneaux gearset) is on the input (turbine) side Input shafts is, if actuated S1 , R2   or C1   and C2   (the common Ravigneaux carrier 1 + 2) Output shaft is R2   (the ring gear of the outer Ravigneaux gearset  ↑     Total Ratio Span (Total Ratio Spread · Total Gear Ratio) i 1 i n {\displaystyle {\tfrac {i_{1}}{i_{n}}}} A wider span enables the downspeeding when driving outside the city limits increase the climbing ability when driving over mountain passes or off-road or when towing a trailer    ↑     Ratio Span's Center ( i 1 i n ) 1 2 {\displaystyle (i_{1}i_{n})^{\tfrac {1}{2}}} The center indicates the speed level of the transmission Together with the final drive ratio it gives the shaft speed level of the vehicle  ↑     Average Gear Step ( i 1 i n ) 1 n − 1 {\displaystyle ({\tfrac {i_{1}}{i_{n}}})^{\tfrac {1}{n-1}}} With decreasing step width the gears connect better to each other shifting comfort increases   ↑     Sun 1: sun gear of gearset 1: inner Ravigneaux gearset  ↑     Ring 1: ring gear of gearset 1: inner Ravigneaux gearset  ↑     Sun 2: sun gear of gearset 2: outer Ravigneaux gearset  ↑     Ring 2: ring gear of gearset 2: outer Ravigneaux gearset  1    2    3    4     Standard  50:50—   50  % Is Above And 50  % Is Below The Average Gear Step  —  With steadily decreasing gear steps (yellow highlighted line Step ) and a particularly large step from 1st to 2nd gear the lower half of the gear steps  (between the small gears; rounded down, here the first 1) is always larger  and the upper half of the gear steps  (between the large gears; rounded up, here the last 2) is always smaller   than the average gear step  (cell highlighted yellow two rows above on the far right)lower half: smaller gear steps are a waste of possible ratios (red  bold)  upper half: larger gear steps are unsatisfactory (red  bold)   1    2    3    4    5     Standard  R:1—   Reverse And 1st Gear Have The Same Ratio  —  The ideal reverse gear has the same transmission ratio as 1st gear no impairment when maneuvering especially when towing a trailer a torque converter can only partially compensate for this deficiency  Plus 11.11  % minus 10  % compared to 1st gear is good Plus 25  % minus 20  % is acceptable (red) Above this is unsatisfactory (bold)  1    2    3    4    5     Standard  1:2—   Gear Step 1st To 2nd Gear As Small As Possible  —  With continuously decreasing gear steps (yellow marked line Step ) the largest gear step is the one from 1st to 2nd gear,  which for a good speed connection and a smooth gear shift  must be as small as possible A gear ratio of up to 1.6667:1 (5:3) is good Up to 1.7500:1 (7:4) is acceptable (red) Above is unsatisfactory (bold)   1    2    3     From large to small gears (from right to left)  ↑     Standard  STEP—   From Large To Small Gears: Steady And Progressive Increase In Gear Steps  —  Gear steps should increase:  Δ  Step (first green highlighted line Δ  Step ) is always greater than 1As progressive  as possible: Δ  Step is always greater than the previous step  Not progressively increasing is acceptable (red) Not increasing is unsatisfactory (bold)  1    2    3    4    5     Standard  SPEED—   From Small To Large Gears: Steady Increase In Shaft Speed Difference  —  Shaft speed differences should increase:  Δ  Shaft Speed (second line marked in green Δ  (Shaft) Speed ) is always greater than the previous one 1 difference smaller than the previous one is acceptable (red) 2 consecutive ones are a waste of possible ratios (bold)  1    2     inner and outer sun gears of the Ravigneaux planetary gearset  are inverted  ↑     Blocks R1   (ring gear of the inner Ravigneaux gearset) and S2   (sun gear of the outer Ravigneaux gearset)  ↑     Blocks C1   and C2   (the common Ravigneaux carrier 1 + 2)  ↑     Couples S1   (sun gear of the inner Ravigneaux gearset) with the turbine  ↑     Couples S2   (sun gear of the outer Ravigneaux gearset) with the turbine  ↑     Couples C1   and C2   (the common Ravigneaux carrier 1 + 2) with the turbine