Trek Marlin 4 Gen 3 vs Trek Marlin 5 Gen 3
A side by side comparison of two mountain bikes available in Australia, on price and specs. The Trek Marlin 4 Gen 3 is the lower-priced of the two.
Which should you choose?
Same frame and geometry, so the choice is about parts. The Marlin 5 adds a ninth gear, a fork you can lock out, Shimano brakes and rack and kickstand mounts.
Trek Marlin 4 Gen 3
Choose the Marlin 4 if you mostly ride bike paths and easy dirt, want the lowest price, or need the XXS size (the Marlin 5 starts at XS).
Trek Marlin 5 Gen 3
Choose the Marlin 5 if you will ride hills or real trails, or want to commute: the fork lockout helps on the road and the mounts take a rack.
Desk research by BikeFinder from both bikes' published specs and geometry, checked 2 Nov 2026. Not a ride test.
Key differences
- Price: the Marlin 4 Gen 3 costs $150 less at the prices shown.
- Gearing: 1x8 Shimano CUES on the Marlin 4 Gen 3, 1x9 Shimano CUES on the Marlin 5 Gen 3.
- Tyre clearance: the Marlin 5 Gen 3 is listed for tyres up to 61 mm; the Marlin 4 Gen 3 does not publish a figure.
- Sizes: 8 on the Marlin 4 Gen 3 (XXS, XS, S, M, ML, L, XL, XXL), 7 on the Marlin 5 Gen 3 (XS, S, M, ML, L, XL, XXL).
Worked out from each bike's published specification and the price shown on its page. The full side by side table and a to-scale geometry overlay are below.
| 2 of 4 bikesDeltas are against the baseline | |||
|---|---|---|---|
| Price and where to buy | |||
| Current Australian price | $849.99Lowest | $999.99 | |
| RRP | $849.99 | $999.99 | |
| Price source | At Trek Australia. Stock not confirmed, checked 16 Oct 2026. | At Trek Australia. Stock not confirmed, checked 16 Oct 2026. | |
| Retailers | trekbikes.com | trekbikes.com | |
| Overview | |||
| Category | Mountain | Mountain | |
| Type | Non-electric | Non-electric | |
| Model year | 2026 | 2026 | |
| Frame and suspension | |||
| Frame | Aluminium | Aluminium | |
| Fork | SR Suntour XCE 28 | SR Suntour XCT 30 | |
| Suspension | Hardtail | Hardtail | |
| Front travel | 100 mm | 100 mmsame | |
| Dropper post | No, rigid seatpost | No, rigid seatpost | |
| Wheels and tyres | |||
| Wheelset | Bontrager Connection, double-wall, 32-hole, 20 mm width, Schrader valve | Bontrager Connection, double-wall, 32-hole, 20 mm width, Schrader valve | |
| Wheel size | 29 inch | 29 inch | |
| Stock tyres | 29x2.40 (size M; varies by size) | 29x2.40 (size M; varies by size) | |
| Max tyre clearance | Not published | 61 mm | |
| Drivetrain | |||
| Groupset | Shimano CUES | Shimano CUES | |
| Shifting | Mechanical, 1x | Mechanical, 1x | |
| Crank | ProWheel alloy, 30T narrow-wide steel ring, 170 mm length (size M; varies by size) | Shimano CUES U4001, 32T, 52mm chain line, 170 mm length (size M; varies by size) | |
| Chainrings | 30 | 32 | |
| Cassette | Shimano HG300, 11-45, 8-speed | Shimano LINKGLIDE LG300, 11-46, 9-speed | |
| Cassette speeds | 8 | 9 | |
| Lowest gearRatio of smallest ring to biggest cog. Lower is easier climbing. | 0.67Lowest | 0.70+0.03 | |
| Highest gearBiggest ring to smallest cog. Higher is a faster top speed. | 2.73 | 2.91+0.18 | |
| Gearing character | Very low climbing gear | Very low climbing gear | |
| Brakes and weight | |||
| Brakes | Tektro HD-M276 hydraulic disc | Shimano MT200 hydraulic disc | |
| Rotors | 160/180mm | 160/180mm | |
| Weight | 14.9 kgLowest | 15.1 kg+0.20 kg | |
| Geometry | |||
| Size shown | M | M | |
| Stack | 609 mm | 609 mmsame | |
| Reach | 440 mm | 440 mmsame | |
| Stack to reachHigher is more upright, lower is more stretched out. | 1.38 | 1.38same | |
| Head angleLower (slacker) is calmer at speed, higher (steeper) is quicker steering. | 66.5 deg | 66.5 degsame | |
| Seat angle | 74.0 deg | 74.0 degsame | |
| Wheelbase | 1,163 mm | 1,163 mmsame | |
| Chainstay | 438 mm | 438 mmsame | |
| BB drop | 60 mm | 60 mmsame | |
Geometry overlay
- Trek Marlin 4 Gen 3 (size M) is the baseline.
- Trek Marlin 5 Gen 3 (size M): identical on every published figure.
Stack, reach, head and seat angles, wheelbase, chainstay and BB drop are drawn to scale from published charts. Tube shapes are schematic.
BikeFinder Data Profile. Geometry and component figures are researched from published manufacturer and retailer sources, not physical ride tests, and can vary by model year.
Specs and pricing are listed in AUD and sourced from Australian retail listings. Confirm current details with the seller before purchase.