Does Lexus GX470 have timing belt or chain?

The GX470 uses a timing belt, not a timing chain.

The 2003–2009 Lexus GX470 is powered by the 4.7-liter 2UZ-FE V8. In this model, Toyota’s design relies on a timing belt to synchronize the camshafts with the crankshaft, rather than a chain. Because it’s a belt-driven setup, maintenance intervals and timely replacement are critical to prevent costly engine damage. This article outlines what that means for owners, including typical replacement intervals, what parts are typically replaced alongside the belt, and common warning signs of belt wear.

Key facts about the GX470 timing belt

Below is a concise guide to the timing belt on the GX470, covering replacement intervals, what parts are commonly changed alongside the belt, and typical costs.

• The GX470 uses a timing belt rather than a timing chain to drive the camshafts.


• Replacement interval is typically around 90,000 miles (about 145,000 kilometers), but always verify with your owner's manual or dealer for your specific year and region.


• When changing the belt, many technicians also replace the water pump, tensioners, and idler pulleys to reduce the risk of belt-related failures in the near term.


• Because the engine is interference, belt failure can cause valves to strike pistons, potentially causing major, costly damage.


• Typical service costs vary by region and shop but can range from roughly $500 to $1,000 or more, depending on parts and labor, with higher prices at dealerships.

Regular planning for belt service helps avoid unexpected breakdowns and aligns maintenance with other service tasks such as fluids and filters.

Warning signs of belt wear or imminent failure

Be alert for the following indicators that the timing belt or related components may need service.

• Squealing or chirping noises from the front of the engine, especially on cold starts or during acceleration.


• Visible signs of wear such as cracks, fraying, glazing, or missing teeth on the belt if you can inspect it safely.


• Oil or coolant contamination on the belt surface, which can degrade belt material and tensioners.


• Engine misfire, rough idle, reduced power, or the Check Engine Light coming on due to belt-driven accessory issues (e.g., water pump, cam timing variance).


• Overheating or coolant leaks indicative of a failing water pump, which is commonly replaced with the belt.

If any of these signs appear, stop driving if safe to do so and have a qualified mechanic inspect the belt promptly to avoid a breakdown.

Summary

In short, the Lexus GX470 uses a timing belt, not a chain, to drive its 4.7L V8. Plan belt replacement around the 90,000-mile mark (check your manual for specifics) and replace the water pump and tensioners at the same time. Recognize warning signs early, as a belt failure can cause serious engine damage in this interference design. Regular maintenance helps keep the GX470 reliable for years to come.

When should timing belts be replaced on GX470?

Most timing belts will need to be replaced as part of regular maintenance every 60,000 to 100,000 miles, and most related problems are caused by not replacing it when you're supposed to. If the timing belt is starting to go bad, the engine will run poorly and the check engine light will likely come on.

What year to avoid Lexus GX470?

The 2003 Lexus GX470 is often cited as the worst model year due to drivetrain issues like clunking noises, and the 2006 model also received a high number of complaints, particularly for drivetrain problems. Other years to be cautious about include models with the optional KDSS system for off-road enthusiasts due to potential costs, and early models (2004 and 2005) for dashboard cracks, dry-rotted wheels, and less engine power compared to later models. 
You can watch this video to learn about common problems to look for when buying a Lexus GX470: 52sRob DrivesYouTube · Feb 11, 2021
Specific model years to be cautious about

• 2003 Lexus GX470: Considered the worst model year by some sources due to specific drivetrain issues, such as clunking and squealing noises, and higher repair costs. 
• 2006 Lexus GX470: Received a high number of owner complaints, particularly regarding drivetrain problems. 
• Models with KDSS: If you plan to heavily modify the vehicle for off-roading, models with the Kinetic Dynamic Suspension System (KDSS) may be best to avoid due to potential complexity and cost of repairs or modifications. 

Common issues across the GX470 lifespan

• Drivetrain issues: Reports of clunking and squealing noises have been associated with certain model years. 
• Dashboard cracks: A common and potentially expensive issue across many model years, especially in warmer climates. 
• Timing belt and water pump: A crucial maintenance item. The timing belt should be replaced around every 90,000 miles, or the vehicle should have a documented history of this replacement. 
• Navigation system: The built-in navigation system is outdated and can be difficult to upgrade or repair. Many owners recommend using a smartphone for navigation instead. 
• Suspension and transmission: During a test drive, listen for unusual noises from the suspension and check for smooth transmission shifts, as these can indicate wear. 

This video discusses the maintenance of a Lexus GX470, including the timing belt replacement: 58sCar WizardYouTube · Feb 22, 2022

Does a Lexus GX470 have a timing belt or chain?

A Lexus GX470 has a timing belt, not a chain. This belt needs to be replaced periodically, typically around every 90,000 miles or 8 years, and failure can cause catastrophic engine damage because it is an interference engine.
 

• Timing belt: The GX470 uses a timing belt for its 4.7L V8 engine. 
• Replacement interval: The belt should be replaced approximately every 90,000 miles or 8 years, whichever comes first. 
• Interference engine: The engine is an interference type, meaning if the timing belt breaks, the pistons will collide with the valves, leading to severe internal damage. 
• Next model: The newer GX460 model, which uses a 4.6L V8, has a timing chain instead. 

How much does it cost to replace a timing belt on a 2004 Lexus GX470?

The average cost to replace the timing belt on a 2004 Lexus GX470 is approximately $1,411, but can range from around $409 to over $2,400 depending on labor rates and whether other components like the water pump are replaced. The high cost is due to the extensive labor involved, as many parts must be disassembled to access the belt. For a complete job including the water pump, parts and labor can push the price to nearly $2,000. 
Cost breakdown and factors

• Parts cost: The timing belt itself is inexpensive, but other parts like the water pump, tensioners, and idlers are often replaced at the same time to avoid repeating the labor-intensive process later. 
• Labor cost: Labor is the biggest factor. The job requires several hours of work, and hourly rates vary between shops. 
• Price variations:
  • Some sources estimate a range as low as $409 to $919. 
  • Other estimates for the 2004 model are around $1,411. 
  • A full timing belt, water pump, and seal replacement job can cost up to $1,964.93 at a Toyota dealership. 
  • Some quotes for a timing belt and water pump job are around $1,210 at a Lexus dealer. 

What to do to get a better price

• Get multiple quotes: Shopping around at different shops, including independent mechanics and dealerships, is the best way to find a competitive price. 
• Ask about packages: Inquire about a comprehensive kit that includes the timing belt, water pump, and other seals to save on labor if they fail in the future. 
• Negotiate: Be prepared to negotiate, especially if you find lower quotes elsewhere.