2003-2023 model years · 4,600+ owner reports · Updated April 2026
According to Au7o's analysis of 4,600+ owner reports, the 2003-2023 Lexus GX has 3 documented known issues. No issues are rated critical, indicating generally reliable ownership. The most commonly reported issue is Secondary Air Injection Pump Failure with 2,200 owner reports. Across all issues, repair costs range from $400 to $3,500. DIY maintenance guides at au7o.io.
On the 2003-2009 Lexus GX 4.7L 2UZ-FE, the secondary air injection (SAI) system pump and switching valves fail due to moisture intrusion and corrosion. The SAI pump introduces fresh air into the exhaust during cold starts to reduce emissions, but the pump motor corrodes internally and the switching valves stick. This triggers a check engine light with SAI-related codes.
Replace the secondary air injection pump and switching valves. Clean or replace the air injection check valves. Clear codes and verify operation. Some owners in non-emissions-testing states choose to bypass the system entirely with a tune.
Parts and tips from 2,200+ owners who fixed this issue
On the 2010-2023 Lexus GX 4.6L 1UR-FE, the Kinetic Dynamic Suspension System (KDSS) on the GX460 develops hydraulic fluid leaks from the stabilizer bar actuators and hydraulic lines. Leaks cause the KDSS warning light to illuminate and the system to become inoperative, resulting in increased body roll and a less controlled ride. The front actuators are the most common failure point.
Replace the leaking KDSS actuator(s) and hydraulic lines. Refill and bleed the system with the correct Toyota KDSS fluid. Both front and rear actuators should be inspected even if only one is leaking. Some owners disconnect the KDSS system and install conventional sway bars.
Parts and tips from 1,500+ owners who fixed this issue
On the 2003-2009 Lexus GX 4.7L 2UZ-FE, the center differential lock actuator on the GX470 fails due to internal motor wear and electrical contact corrosion. When the actuator fails, the center diff lock cannot be engaged for low-range off-road use. The actuator is mounted on the transfer case and is exposed to road debris and moisture.
Replace the center differential lock actuator motor. The actuator is accessible from under the vehicle on the transfer case. Use the OEM Toyota actuator for reliability. After replacement, verify engagement by testing in a straight line at low speed on a loose surface.
Parts and tips from 900+ owners who fixed this issue
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According to Au7o's analysis of 4,600+ owner reports, the 2003-2023 Lexus GX has 3 documented issues. The most frequently reported are: Secondary Air Injection Pump Failure, AHC (Adaptive Hydraulic) Suspension Leak, Center Differential Lock Actuator Failure. None are rated critical, but regular maintenance is recommended.
The 2003-2023 Lexus GX has 3 known issues documented across 4,600+ owner reports. No issues are rated critical, suggesting generally good reliability. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
Repair costs for known Lexus GX issues range from $400 to $3,500, depending on the specific problem and whether you choose DIY or professional repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
Reliability varies across model years of the Lexus GX. Based on owner reports, issues are most commonly reported in earlier model years. Au7o recommends checking the specific known issues for your target year before purchasing, and having a pre-purchase inspection performed by a qualified mechanic. Our known issues database covers the 2003-2023 Lexus GX with 3 documented issues from 4,600+ owner reports.
The secondary air injection (SAI) system pump and switching valves fail due to moisture intrusion and corrosion. The SAI pump introduces fresh air into the exhaust during cold starts to reduce emissions, but the pump motor corrodes internally and the switching valves stick. This… Repairs typically run $800-$2,000. Severity: medium.
The Kinetic Dynamic Suspension System (KDSS) on the GX460 develops hydraulic fluid leaks from the stabilizer bar actuators and hydraulic lines. Leaks cause the KDSS warning light to illuminate and the system to become inoperative, resulting in increased body roll and a less contr… Repairs typically run $1,000-$3,500. Severity: medium.
The center differential lock actuator on the GX470 fails due to internal motor wear and electrical contact corrosion. When the actuator fails, the center diff lock cannot be engaged for low-range off-road use. The actuator is mounted on the transfer case and is exposed to road de… Repairs typically run $400-$1,000. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
