GM Service Manual Online
For 1990-2009 cars only

Complaint/Condition

Possible Cause

correction

Knock at Low Speeds

    • Worn drive axle joint
    • Worn side gear or pinion gear bores
    • Inspect drive axle joint and replace if necessary.
    • Inspect differential case and replace if necessary.

Noisy Around Turns

Worn differential gears

Inspect differential gears and replace if necessary.

Clunk or Acceleration or Deceleration

    • Loose engine mounts
    • Worn inboard drive axle joint
    • Worn differential pinion shaft
    • Worn side gear hub counterbore
    • Inspect engine mounts and tighten if necessary.
    • Inspect inboard drive axle joint and replace if necessary.
    • Inspect differential pinion shaft and replace if necessary.
    • Inspect side gear hub counterbore and replace if necessary.

Click Noise On Turns

Worn outboard drive axle C/V joint

Inspect C/V joint and replace if necessary.

Noisy in Neutral With Engine Running

    • Worn input gear bearing
    • Worn speed gear bearing
    • Worn bearing races
    • lnspect bearing and replace if necessary.
    • lnspect bearing and replace if necessary.
    • lnspect bearing race and replace if necessary.

Noisy in First Gear Only

    • Worn, chipped, or scored 1st speed constant-mesh gears
    • Worn, shipped, or scored 1st/2nd synchronizer
    • lnspect gears and replace if necessary.
    • lnspect synchronizer and replace if necessary.

Noisy in Second Gear Only

    • Worn, chipped, or scored 2nd speed constant-mesh gears
    • Worn, chipped, or scored 1st/2nd synchronizer
    • lnspect gears and replace if necessary.
    • lnspect synchronizer and replace if necessary.

Noisy in Third Gear Only

    • Worn, chipped, or scored 3rd speed constant-mesh gears
    • Worn, chipped, or scored 3rd/4th synchronizer
    • lnspect gears and replace if necessary.
    • lnspect synchronizer and replace if necessary.

Noisy in Fourth Gear Only

    • Worn, chipped, or scored 4th speed constant-mesh gears
    • Worn, chipped, or scored 3rd/4th synchronizer
    • Worn, chipped, or scored output gear
    • Worn, chipped, or scored output gear
    • lnspect gears and replace if necessary.
    • lnspect synchronizer and replace if necessary.
    • lnspect gear and replace if necessary.
    • lnspect gear and replace if necessary.

Noisy in Fifth Gear Only

    • Worn, chipped, or scored 5th speed constant-mesh gears
    • Worn, chipped, or scored 5th synchronizer
    • Worn, chipped, or scored output gear
    • lnspect gears and replace if necessary.
    • lnspect synchronizer and replace if necessary.
    • lnspect gear and replace if necessary.

Noisy in Reverse Only

    • Worn, chipped, or scored reverse speed constant-mesh gears
    • Worn or damaged output gear
    • lnspect gear and replace if necessary.
    • lnspect gear and replace if necessary.

Noisy in All Gears

    • Fluid level low
    • Worn or damaged wheel bearings
    • Worn, chipped, or scored input/output shaft gear
    • Worn output gear bearing
    • Loose shift rail guide bolt
    • Worn, chipped, or scored 1st, 2nd, 3rd, 4rd, 5th, or Reverse gears.
    • Add fluid to proper level.
    • Inspect wheel bearing and replace if necessary.
    • Inspect gear and replace if necessary.
    • Inspect output gear bearing and replace if necessary.
    • Tighten shift rail guide bolt.
    • Inspect components and replace as necessary.

Slips Out of Gear

    • Loose transaxle mounts
    • Bent or worn cables
    • Broken or loose input gear bearing retainer
    • Worn or bent shift fork
    • Dirty clutch housing and engine
    • Stiff shift lever seal
    • Manual transaxle internal shift mechanism malfunction
    • Tighten or replace mounts.
    • Inspect cables and replace if necessary.
    • Inspect shift fork and replace if necessary.
    • Inspect shift fork and replace if necessary.
    • Clean clutch housing and engine.
    • Inspect seal and replace if necessary.
    • Disassemble transaxle, repair as necessary.

Slips Out of Gear While Accelerating

    • Missing or misadjusted first gear thrust bearing or washer
    • Worn or damaged fist gear spline lock on 1st/2nd synchronizer
    • Worn of damaged second gear spline lock on 1st/2nd synchronizer
    • Worn or damaged third gear spline lock on 3rd/4th synchronizer
    • Worn or damaged fourth gear spline lock on 3rd/4th synchronizer
    • Worn or damaged 5th gear spline lock on the 5th/Reverse synchronizer
    • Worn or damaged Reverse gear spline lock on the 5th/Reverse synchronizer
    • Worn or damaged 1st, 2nd, 3rd, 4th, 5th or reverse gear spline lock
    • Manual transaxle internal shift mechanism malfunction
    • Inspect bearing and washer and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Inspect spline lock and replace if necessary.
    • Disassemble transaxle, repair as necessary.

Slips Out of Gear While Coasting

    • Damaged, worn, or missing shift rails
    • Manual transaxle internal shift mechanism malfunction
    • Inspect shift rails and replace if necessary.
    • Disassemble transaxle, repair as necessary.

Fluid Leakage

    • Fluid level high
    • Damaged axle shaft seals
    • Vent cap plugged
    • Poor sealing on shift cover
    • Poor sealing between case and clutch housing
    • Poor sealing on rear cover
    • Poor sealing or loose back-up lamp switch
    • Poor sealing or loose vehicle speed sensor
    • Drain excess fluid.
    • Inspect axle shaft seals and replace if necessary.
    • Clear or replace vent cap.
    • Replace sealer on shift cover.
    • Replace sealer between case and clutch housing and tighten.
    • Replace sealant on rear cover and tighten.
    • Tighten switch or replace sealant as needed.
    • Tighten sensor or replace sealant as needed.