What is a wet belt?

Also known as a ‘wet cambelt’, a wet belt is a key component that is used to synchronise the rotation of the engine’s crankshaft and camshaft, so that the valves open and close at the same time.

In this car maintenance guide, we look at how it works, common faults, and replacement costs.

What is a wet belt on a car?

A wet belt is a type of timing belt or cambelt that is used in a car’s engine to synchronise the crankshaft and camshaft, to ensure that the engine valves open and close at the exact time as the pistons do.

Unlike a conventional cambelt, a wet belt is submerged in the engine oil. This helps reduce friction, engine noise, and reduce fuel consumption.

For these reasons, they are increasingly popular in new cars.

However, they need to correct type and quality of engine oil to maintain performance and protect the surrounding parts from damage.

As a wet belt ages and is used over time, it can deteriorate and break down. As a result, particles can get into the lubricant and cause further issues – potentially serious engine damage.

It is important to regularly service your vehicle and replace liquids when advised to do so.

Does my car have a wet belt?

The easiest way to know if your car has a wet belt, is to check the car owner’s manual.

You can also check on the manufacturer’s website for the details on your vehicle, including what belt it has, and how often it should be serviced and replaced.

It is important to know that not all cars use a wet belt – and some makes and models will have subtle differences in how the system works.

If your car does have a wet belt, it is vital that you use the correct engine oil, which will also be specified in the manual or on the manufacturer’s website.

Using the wrong oil, or not regularly servicing your car, will likely result in major problems with potentially expensive fixes.

• Serpentine belt replacement cost guide
• Guide to timing belt replacements
• What is a cambelt? How do you replace it?

Wet belt replacement costs

In the UK, the average cost to replace a cambelt (which includes wet belts) is around £427.

Here are the average prices to replace a cambelt in the UK by manufacturer:

^{Source: whocanfixmycar data for cambelts, August 2026 (rounded to nearest whole number)}

Common wet belt problems

Wet belts are designed to last many years with the correct servicing and maintenance, however, they can develop issues over time.

Here are some common wet belt faults to look out for:

• Deterioration: The rubber in the belt wears down over time and particles can clog up the engine oil and make lubrication less effective
• Blockages: Dirt and debris build up can block the surrounding components, which can lead to major engine failure
• Premature wear: Lack of servicing, use of incorrect engine oil, poor maintenance, and constant high temperatures will wear the belt quicker than stated in the owner’s manual
• Snapped belt: In severe cases, the belt can snap under pressure causing the engine to suffer significant damage

Why choose the RAC for a wet belt change?

The cambelt, or timing belt, keeps your engine's valves and pistons working in sync. Over time, the cambelt wears down and can snap, which could cause engine damage.

We recommend that you replace your cambelt in line with your manufacturer service schedule.

Book a local RAC Approved Garage that you can trust today.