FixVault

Problem Symptoms Table

WARNING: This page is about a different car, the 2006 Lexus GS 430 and 2006 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.

Use the table below to help find the cause of the problem. The causes of the problem are listed in order of probability in the "Suspected area" column. Check each part in order. If necessary, replace these parts.

Front Differential (for 4WD) 

PROBLEM SYMPTOMS CHART

Symptom Suspected area See
Noise in front differential Oil level (Low or wrong grade) DIFFERENTIAL OIL 
Ring gear or drive pinion (Worn or chipped) REMOVAL 
Backlash adjustment (Defective) REMOVAL 
Preload adjustment (Defective) REMOVAL 
Tooth contact between ring gear and drive pinion (Defective) REMOVAL 
Bearing (Worn) REMOVAL 
Oil leak from front differential Oil level (Too high or wrong grade) DIFFERENTIAL OIL 
Oil seal (Worn or damaged) REMOVAL 
Seal packing (Damaged) REMOVAL 

Rear Differential (for 3GR-FSE) 

REAR DIFFERENTIAL SPECIFICATIONS

Symptom Suspected area See
Noise in rear differential Oil level (Low or wrong grade) DIFFERENTIAL OIL 
Ring gear or drive pinion (Worn or chipped) REMOVAL 
Backlash adjustment (Defective) REMOVAL 
Preload adjustment (Defective) REMOVAL 
Tooth contact between ring gear and drive pinion (Defective) REMOVAL 
Bearing (Worn) REMOVAL 
Oil leak from rear differential Oil level (Too high or wrong grade) DIFFERENTIAL OIL 
Side gear shaft oil seal (Worn or damaged) REAR DIFFERENTIAL SIDE GEAR SHAFT OIL SEAL (for 3GR-FSE) 
Seal packing (Damaged) REMOVAL 

Rear Differential (for 3UZ-FE) 

REAR DIFFERENTIAL SPECIFICATIONS

Symptom Suspected area See
Noise in rear differential Oil level (Low or wrong grade)  3
Ring gear or drive pinion (Worn or chipped) REMOVAL 
Backlash adjustment (Defective) REMOVAL 
Preload adjustment (Defective) REMOVAL 
Tooth contact between ring gear and drive pinion (Defective) REMOVAL 
Bearing (Worn) REMOVAL 
Oil leak from rear differential Oil level (Too high or wrong grade)  3
Side gear shaft oil seal (Worn or damaged) REAR DIFFERENTIAL SIDE GEAR SHAFT OIL SEAL (for 3UZ-FE) 
Seal packing (Damaged) REMOVAL