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Are diesel wet belt engines better than petrols?

After researching the much negatively publicised 'dreaded wet belt' I was amazed to discover that most forums I have visited for advice, no one has any stories of failure on the diesel engines - just the Ecoboosts.

Are there any figures available to suggest that the diesel engines used in the car rather than the Transit are susceptible to failure. Or like any other car with belt or chain are as long as serviced and maintained - replaced at reasonable interval not really an issue?

Asked on 11 November 2025 by Cor Bear

Answered by David Ross
There is no accurate data available to indicate the failure rate of wet belts across different engine types. Anecdotally it appears that petrol engines are more susceptible, but it is likely that there are several times the number of petrol wet belt engines compared to diesels, so this may not be an accurate conclusion. Ultimately it is correct that if the manufacturer's recommended service intervals are followed the chances of failure are still relatively low.
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