Main Shaft Inspection

WARNING: This page is about a different car, the 2006 Suzuki XL-7. However, it is still accessible from the selected car via links, so may be relevant.

Reference: MAIN SHAFT DISASSEMBLY

Check clearance "a" between synchronizer ring and gear, width of index protrusion "b" in synchronizer ring, key slot width "c" in high and low speed synchronizer hub and each chamfered tooth of gear and synchronizer ring and replace with new one, if necessary. Also, check gear tooth.

Clearance "a" between synchronizer ring and gear (Main shaft) (1st, 2nd and 3rd)

Standard: 0.65 - 1.75 mm (0.026 - 0.069 in.)

Service limit: 0.5 mm (0.020 in.)

WIDTH OF INDEX PROTRUSION "b" (MAIN SHAFT)

	Standard	Service limit
1st	4.8 - 5.0 mm (0.189 - 0.197 in.)	4.5 mm (0.177 in.)
2nd	5.7 - 5.9 mm (0.224 - 0.232 in.)	5.4 mm (0.213 in.)
3rd	4.3 - 4.5 mm (0.169 - 0.177 in.)	4.0 mm (0.157 in.)

KEY SLOT WIDTH "c" (HIGH AND LOW SPEED SYNCHRONIZER HUB)

	Standard
1st	9.0 - 9.1 mm (0.354 - 0.358 in.)
2nd	9.0 - 9.1 mm (0.354 - 0.358 in.)
3rd	8.0 - 8.1 mm (0.315 - 0.319 in.)

Fig 1: Identifying Clearance Between Synchronizer Ring And Gear, Width Of Index Protrusion & Key Slot Width

Courtesy of SUZUKI OF AMERICA CORP.

Measure width of high speed gear shift fork end "a" and groove width of high speed synchronizer sleeve "b" and then calculate clearance "c" as follows:
Clearance "c" = "b" - "a"

If clearance exceeds limit, replace fork and sleeve.

Clearance "c" between fork and sleeve

Standard: 0.15 - 0.35 mm (0.006 - 0.014 in.)

Limit: 1.0 mm (0.039 in.)

Fig 2: Identifying Width Of High Speed Gear Shift Fork End And Groove Width Of High Speed Synchronizer Sleeve
Courtesy of SUZUKI OF AMERICA CORP.
Measure groove "a" of low speed gear shift fork and flange width "b" of low speed synchronizer sleeve and then calculate clearance "c" as follows:
Clearance "c" = "b" - "a"

If clearance exceeds limit, replace fork and sleeve.

Clearance "c" between fork and sleeve

Standard: 0.15 - 0.41 mm (0.006 - 0.016 in.)

Limit: 1.0 mm (0.039 in.)

Fig 3: Identifying Groove Of Low Speed Gear Shift Fork And Flange Width Low Speed Synchronizer Sleeve
Courtesy of SUZUKI OF AMERICA CORP.

Check diameter of main shaft (1) and thickness of main shaft (1) flanges as shown in the figure. If measured value is out of specification, replace main shaft (1).

MAIN SHAFT SPECIFICATIONS (DIAMETER AND THICKNESS)

Measuring portion	Standard
A	46.984 - 47.000 mm (1.8500 - 1.8504 in.)
B	37.984 - 38.000 mm (1.4954 - 1.4961 in.)
C	4.80 - 5.20 mm (0.1890 - 0.2047 in.)
D	38.979 - 38.995 mm (1.5346 - 1.5352 in.)

Fig 4: Identifying Main Shaft

Courtesy of SUZUKI OF AMERICA CORP.

Using "V" blocks (1) and dial gauge (2), check runout.
If runout exceeds limit below, replace main shaft (3).

Main shaft runout

Limit: 0.015 mm (0.0006 in.)

Fig 5: Identifying V Blocks, Dial Gauge & Main Shaft
Courtesy of SUZUKI OF AMERICA CORP.
Using cylinder gauge (1), check inside diameter of each gear. If its inside diameter exceeds specification, replace it.
Inside diameter (standard) of gear

1st gear: 46.015 - 46.040 mm (1.8116 - 1.8126 in.)

2nd gear: 53.015 - 53.040 mm (2.0872 - 2.0882 in.)

3rd gear: 44.015 - 44.040 mm (1.7329 - 1.7339 in.)

Fig 6: Identifying Cylinder Gauge
Courtesy of SUZUKI OF AMERICA CORP.
Check chamfered part of each sleeve for damage and excessive wear, and replace as necessary.
Check each synchronizer key and synchronizer spring and replace as necessary.
Check splined portions and replace parts if excessive wear is found.
Check 2nd gear (1) thrust clearance by using thickness gauge (2). If clearance is out of specification, repress-fit or replace defective part.
2nd gear thrust clearance

Standard: 0.10 - 0.25 mm (0.004 - 0.010 in.)

Fig 7: Identifying 2nd Gear & Thickness Gauge
Courtesy of SUZUKI OF AMERICA CORP.
Check low gear (1) thrust clearance by using thickness gauge (2).
If clearance is out of specification, repress-fit or replace main shaft bearing and 5th gear.

Low gear thrust clearance

Standard: 0.15 - 0.45 mm (0.006 - 0.018 in.)

Fig 8: Identifying Low Gear & Thickness Gauge
Courtesy of SUZUKI OF AMERICA CORP.