With Assessment[a][b] |
Planetary Gearset: Teeth[c] Lepelletier Gear Mechanism |
Count |
Total[d] Center[e] |
Avg.[f] |
Simple |
Ravigneaux |
|
Model |
Version First Delivery |
S1[g] R1[h] |
S2[i] R2[j] |
S3[k] R3[l] |
Brakes Clutches |
Ratio Span |
Gear Step[m] |
Gear Ratio |
R
 |
1
 |
2
 |
3
 |
4
 |
5
 |
6
 |
Step[m] |
[n] |
 |
[o] |
 |
 |
 |
 |
Δ Step[p][q] |
|
|
 |
 |
 |
 |
|
Shaft Speed |
 |
 |
 |
 |
 |
 |
 |
Δ Shaft Speed[r] |
 |
 |
 |
 |
 |
 |
 |
|
Aisin AWTF-80 SC |
450 N⋅m (332 lb⋅ft) 2005[6] |
50 90 |
36 44 |
44 96 |
2 3 |
6.0494 1.6865 |
1.4333[m] |
Gear Ratio |
−3.3939[n]
 |
4.1481
 |
2.3704[o]
 |
1.5556
 |
1.1546[q]
 |
0.8593
 |
0.6857[r]
 |
Step |
0.8182[n] |
1.0000 |
1.7500[o] |
1.5238 |
1.3472 |
1.3436 |
1.2532 |
Δ Step[p] |
|
|
1.1484 |
1.1311 |
1.0027[q] |
1.0722 |
|
Speed |
-1.2222 |
1.0000 |
1.7500 |
2.6667 |
3.5926 |
4.8272 |
6.0494 |
Δ Speed |
1.2222 |
1.0000 |
0.7500 |
0.9167 |
0.9259 |
1.2346 |
1.2222[r] |
|
ZF 6HP |
All[b] · 2000[s] |
37 71 |
31 38 |
38 85 |
2 3 |
6.0354 1.6977 |
1.4327[m] |
Gear Ratio |
−3.4025[n]
 |
4.1708
 |
2.3397[o]
 |
1.5211
 |
1.1428[q][r]
 |
0.8672
 |
0.6911
 |
Step |
0.8158[n] |
1.0000 |
1.7826[o] |
1.5382 |
1.3311 |
1.3178 |
1.2549 |
Δ Step[p] |
|
|
1.1589 |
1.1559 |
1.0101[q] |
1.0502 |
|
Speed |
-1.2258 |
1.0000 |
1.7826 |
2.7419 |
3.6497 |
4.8096 |
6.0354 |
Δ Speed |
1.2258 |
1.0000 |
0.7826 |
0.9593 |
0.9078[r] |
1.1599 |
1.2258 |
|
Ratio R & Even |
 |
 |
 |
 |
Ratio Odd |
 |
 |
 |
|
Algebra And Actuated Shift Elements |
Brake A[t] |
|
❶ |
❶ |
❶ |
❶ |
|
|
Brake B[u] |
❶ |
|
|
❶ |
|
❶ |
|
Clutch C[v] |
|
|
❶ |
|
|
|
❶ |
Clutch D[w] |
❶ |
❶ |
|
|
|
|
|
Clutch E[x] |
|
|
|
|
❶ |
❶ |
❶ |
|
Layout
- Input and output are on opposite sides
- Planetary gearset 1 is on the input (turbine) side
- Input shafts are R1 and, if actuated, C2/C3 (the combined carrier of the compound Ravigneaux gearset 2 and 3)
- Output shaft is R3 (ring gear of gearset 3: outer Ravigneaux gearset)
Total Ratio Span (Total Ratio Spread · Total Gear Ratio)

- 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

- 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

- 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: inner Ravigneaux gearset
Ring 2: ring gear of gearset 2: inner Ravigneaux gearset
Sun 3: sun gear of gearset 3: outer Ravigneaux gearset
Ring 3: ring gear of gearset 3: outer Ravigneaux gearset
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 2) is always larger
- and the upper half of the gear steps (between the large gears; rounded up, here the last 3) 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)
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)
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)
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 1
- As 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 C2 (carrier 2) and C3 (carrier 3)
Couples C1 (carrier 1) and S2
Couples C1 (carrier 1) with R2 and S3
Couples R1 with C2 (carrier 2) and C3 (carrier 3)
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