Timing Procedures

Special Instructions

Both front and rear countershaft assemblies must be "timed". Correct timing assures the mainshaft gears will be properly centered between the countershafts.

Timing is a simple service procedure completed by marking the appropriate teeth of a gear set prior to installation and placing them in proper mesh during assembly. Since Lightning models are assembled as a single unit, there are three critical gear sets that must be timed. In the order in which they are assembled, these gears include: the splitter gear set, the auxiliary mainshaft drive gear set, and the 3rd/4th gear set.

Since Lightning transmission models contain all helical style gearing and the countershafts are single piece units, the process of marking the gear teeth is unique compared to other models.

Special Tools

• Tool Markers Dye

Procedure -

1. Marking the auxiliary mainshaft splitter gear

2. Prior to installing the splitter gear on the end of the auxiliary mainshaft, clearly mark any two teeth that are directly opposite of each other. Mark the teeth on the front side of the gear identified by the internal clutching teeth.

3. There should be an equal number of unmarked gear teeth between the marked teeth.

1. Marking the auxiliary countershaft gears

2. Locate the timing mark on the rear side of the forward most gear (auxiliary coutershaft driven gear) and mark the two adjacent teeth next to the timing mark as shown.

3. Repeat the procedure for the two teeth on the next gear (auxiliary countershaft splitter gear) that line up exactly with the timing mark on the drive gear.

1. Marking the mainshaft gears

2. Prior to building the mainshaft assembly the auxiliary countershaft drive gear and the 3rd /4th mainshaft gear must be marked for timing purposes. Clearly mark any two teeth that are directly opposite of each other. Mark the teeth on the front side of the gear so the teeth can be identified during transmission assembly.

3. There should be an equal number of unmarked gear teeth between the marked teeth.

1. Marking the front countershaft gears

2. Locate the timing mark on the flat section of the countershaft between the two smallest gears.

3. Mark the two adjacent teeth on the 3rd/4th gear that line up with the timing mark.

1. Meshing the marked gearing during assembly

2. Install the splitter gear.

3. Install the auxiliary countershafts in the transmission case with the timing marks lined up with the splitter gear marked teeth.

4. Install the mainshaft assembly with the marked teeth on the auxiliary drive gear lined up between the marked teeth on the auxiliary countershaft driven gears.

5. Install the countershafts with the two adjacent marked teeth lined up on each side of the marked tooth on the mainshaft gears.

6. Follow the assembly procedures in the "Bench Service" section.