| 8L 45 · 8L 90 | |
|---|---|
| Overview | |
| Manufacturer | General Motors |
| Production | 2014– |
| Body and chassis | |
| Class | 8-speed longitudinal automatic transmission |
| Related | ZF 8HP · Aisin-Toyota 8-speed · MB 9G-Tronic |
| Chronology | |
| Predecessor | 6L 45 · 6L 50 · 6L 80 · 6L 90 |
| Successor | 10L 80 · 10L 90 · 10L 1000 |
The Hydramatic 8L 45 is an 8-speed automatic transmission built by General Motors debuting in the 2016 Cadillac CT6. It is designed for use in longitudinal engine applications attached to the front-located engine[1] with a standard bell housing. It is a hydraulic (hydramatic) design sharing much with the 8L 90 transmission.[2] Estimated weight savings over the heavier duty 8L 90 is 33 lb (15 kg). Gear ratios used enable a wide 7.0 ratio spread.
The 8L 90 is an 8-speed automatic transmission built by General Motors. It is designed for use in longitudinal engine applications either attached to the front-located engine[1] with a standard bell housing or in the rear of the car adjacent to the differential (as in the Corvette). It is a hydraulic (hydramatic) design. GM also produces a similar design with the smaller 8L 45.
Gear Model
|
R | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | Total Span |
Span Center |
Avg. Step |
Compo- nents |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 8L 45 · M5N · 2015 | −3.928 | 4.615 | 3.038 | 2.065 | 1.658 | 1.259 | 1.000 | 0.849 | 0.658 | 7.011 | 1.743 | 1.321 | 4 Gearsets 2 Brakes 3 Clutches |
| 8L 90 · M5U · 2014 | −3.818 | 4.560 | 2.971 | 2.075 | 1.688 | 1.270 | 1.000 | 0.845 | 0.652 | 6.999 | 1.724 | 1.320 | |
| ZF 8HP 70 · 2008[b] | −3.297 | 4.696 | 3.130 | 2.104 | 1.667 | 1.285 | 1.000 | 0.839 | 0.667 | 7.043 | 1.769 | 1.322 | |