Ford began using the BorgWarner BW 1345 transfer case in 1980, and phased it out completely in 1991 in favor of the BW 1356. The 1356's magnesium case is considerably stronger than that of the 1345's aluminum case. Both cases utilize a positive displacement oil pump to provide lubrication to the shaft bearings. This not only promotes longevity of the unit, but makes pickups equipped with this transfer case suitable for towing with minimal bearing failure concerns. The BW 1345 was only offered as a manual shift transfer case, where the newer BW 1356 was offered in both manual and electronic shift versions. Because both transfer cases are chain drive, they require ATF for lubrication as opposed to more viscous gear oils.
BorgWarner BW1345 Specs
| Manufacturer | BorgWarner | |
| Applications | 1980 - 1991 Ford Bronco, F150/F250/F350 | |
| Case | Aluminum, 2 piece | |
| Drive Type | Part time, chain drive, manual shift | |
| Gear Ratios | High Range | 1.00 : 1 (direct drive) |
| Low Range | 2.72 : 1 | |
| Fluid Type/Spec | Automatic transmission fluid (ATF) | |
BorgWarner BW1356 Specs
| Manufacturer | BorgWarner | |
| Applications | 1987 - 1995 Ford Bronco, F150/F250/F350 | |
| Case | Magnesium | |
| Drive Type | Part time, chain drive, manual & electronic shift versions | |
| Gear Ratios | High Range | 1.00 : 1 (direct drive) |
| Low Range | 2.69 : 1 | |
| Fluid Type/Spec | Automatic transmission fluid (ATF) | |
BorgWarner transfer case identification tag location & breakdown