Transfer Case Backlash
- Remove lower left gear housing bolt to drain lubricant. Loosen rear engine mount bolts. DO NOT remove bolts. Bolts are loosened to gain access to cup plug on transfer case.
- Place small drain container under cup plug. Using small chisel, remove cup plug. DO NOT damage transfer case. Backlash Checking Tool (T87P-4020-B) is used for checking backlash. Install backlash checking tool into opening of input gear. Tighten nut on backlash tool. See Fig 1.
Courtesy of FORD MOTOR CO.
- Install dial indicator and magnetic base on lower control arm. Position so that dial indicator tip rests on the backlash checking tool. See Fig 1. Push downward on backlash checking tool and note dial indicator reading. Backlash should be within .012-.024" (3-6 mm) on a 3" (76 mm) radius.
- If backlash is within specification, remove dial indicator and backlash checking tool. Install cup plug and gear housing bolt. Fill transaxle with lubricant. See LUBRICATION . Tighten engine mount bolts to specification.
- Transfer case must be removed if backlash is not within specification. See TRANSFER CASE R & I under REMOVAL & INSTALLATION. Remove old gasket from transfer case. Install .055-.064" (1.40-1.62 mm) maximum thickness gasket (Part No. 7A-191-AA) on transfer case.
- Install transfer case. Recheck backlash as previously done. Compare backlash reading to that of table to determine proper gasket to be used. See BACKLASH SHIM SELECTION table.
BACKLASH SHIM SELECTION
| Backlash Reading In. (mm) |
Shim Part No. |
| .012-.020 (.30-.50) |
7A191-HA |
| .021-.024 (.51-.62) |
7A191-GA |
| .025-.030 (.63-.76) |
7A191-FA |
| .031-.035 (.77-.90) |
7A191-EA |
| .036-.042 (.91-1.06) |
7A191-DA |
| .043-.048 (1.07-1.21) |
7A191-CA |
| .049-.054 (1.22-1.38) |
7A191-BA |
| .055-.064 (1.39-1.62) |
7A191-AA |
- Determine proper gasket to be used. Remove transfer case. Install proper gasket and transfer case. Recheck backlash to ensure proper gasket was used.
- If backlash is within specification, remove dial indicator and backlash checking tool. Install cup plug and gear housing bolt. Fill transaxle with lubricant. See LUBRICATION . Tighten engine mount bolts to specification.