Gates technical experts answer some common questions from mechanics and explain the special properties of timing belts made with PTFE.
It’s rare for Gates Technical Workshops to take place without some discussion about the construction of timing belts in general and, in particular, why so many timing belts contain polytetrafluoroethylene or, PTFE as it is more usually known. Here are the answers to some of the most frequently asked questions.
What is PTFE and why is it used in timing belts?
PTFE is a synthetic material that most automotive technicians will have heard about, not just because it is often associated with items of non‐stick kitchenware. The characteristics of PTFE coatings make it suitable for use in the construction of timing belts.
Its high resistance to water, heat, and corrosion by chemicals are especially useful. PTFE also possesses very low frictional properties, more usually expressed as a low ‘frictional coefficient’. As a result, vehicle manufacturers often specify the use of PTFE in timing belts designed as OE fitment (e.g. VAG TDI engines). And in the aftermarket too, drive system overhauls involving belts made with PTFE have become more and more common.
Are timing belts made with PTFE better than those that are not?
There are performance benefits. With increasingly high loads and average engine operating temperatures rising beyond 120°C, the need for timing belts with improved durability is increasing and PTFE plays an important role in the performance of modern drive systems. Adding a PTFE coating to the fabric cover of the belt’s toothed side and/or backside reduces friction and abrasion, resulting in improved wear resistance. Another major benefit is less noise from the drive.
Belts with PTFE demonstrate significantly lower weight loss/abrasion .
What can you say about the quality of the PTFE used in aftermarket belts?
From a visible inspection, it’s not easy to tell that a belt coating contains PTFE and the amount of PTFE found in aftermarket belts may vary a lot from brand to brand. Some may have only a relatively thin PTFE film on the belt surface. In such cases, with an extended period of high load as well as extreme dynamic belt tensions or high temperatures, such films are likely to wear away quickly, leaving the base fabric material exposed.
The PTFE coating on a timing belt manufactured by Gates penetrates the surface of the fabric. As the PTFE is an integral part of the belt, performance is maintained throughout its intended lifetime. This is one reason why Gates timing belts are characterised by low wear, low noise levels and conform to OE quality standards ‐ without exception.
Why are some PTFE timing belts white, while others are black?
PTFE coated belts can be supplied in a range of different colours, but are more usually either black or white. The colour of the belt has no effect on its performance or function.
PTFE black or white: no differences in performance or function
Is Gates an OE supplier of belts made with PTFE?
Gates has been manufacturing PowerGrip® PTFE coated timing belts since the early 2000s and Alfa Romeo, Avtovaz, Citroën, Fiat, Ford, Hyundai, Kia, Peugeot, Renault, Seat, Skoda, Volvo and Volkswagen are just a few of the vehicle manufacturers that fit them as OE as well as in the aftermarket.
When it’s time to replace an OE Gates timing belt made with PTFE, you can be sure that the aftermarket replacement supplied by Gates will also have been made with PTFE. You can also be sure that it will have been manufactured to the same OE quality standards.