AX3904 V-Belt — Brand Comparison

Compare the AX3904 V-belt across Gates, Continental, Optibelt, Dayco, and Bando.

Equivalent Part Numbers

BrandPart NumberProduct LineProfileLengthWidthPrice
GatesAX3904AX
ContinentalAX3904StandardAX
OptibeltAX3904StandardAX
DaycoAX3904StandardAX
BandoAX3904StandardAX

Verification

All brands produce the AX3904 to the same industry-standard dimensions
Cross-section profile (AX) is standardized across manufacturers
Belt length is identical — direct drop-in replacement
Pulley groove compatibility confirmed (same V-angle)

Why Belt Part Numbers Are the Same Across Brands

Unlike bearings (where SKF uses “2RS1” and NSK uses “DDU” for the same seal type), V-belt manufacturers all use the same industry-standard naming system. An A68 from Gates is the same dimensions as an A68 from Continental, Optibelt, Dayco, or Bando.

The letter designates the cross-section profile (A, B, C for classical; 3V, 5V for narrow) and the number designates the length. This standardization is based on RMA/MPTA and ISO standards that all manufacturers follow.

The differences between brands are in rubber compound, cord construction, and manufacturing quality — which affect belt life and performance under extreme conditions. For standard applications, all brands are fully interchangeable.

Frequently Asked Questions

Can I replace a Gates AX3904 with a Dayco AX3904?

Yes. Both are manufactured to the same industry-standard dimensions. They are direct drop-in replacements for each other.

Which brand of AX3904 belt is best?

Gates is generally considered the premium brand for industrial V-belts. Continental and Optibelt are also high-quality European manufacturers. Dayco is strong in automotive applications. Bando is popular in Asia. For standard applications, any brand will perform well.

What's the difference between AX3904 and AXX3904?

The “X” suffix (e.g., AX68 vs A68) indicates a notched/cogged construction. Notched belts run cooler and are more flexible, allowing use on smaller pulleys. Same length and width — different internal construction.