The WT Series is the six-model Trevi Benne tree shear range that older Australian marketing still describes as “six different sizes”. It has been superseded in the factory catalogue by the WL and WR families, but WT heads were sold here for years, they trade second-hand, and dealer descriptions written around the WT structure are still quoted. This page exists for the used buyer and the fleet owner who already runs one.
Where the WT Series sits in the range
The WT range covered in six steps what the current catalogue covers in six models across two families. Its lower half maps roughly onto the WL Series and its upper half onto the WR family, from the WR10 to the WR20. A new-equipment buyer should be quoted on WL or WR data sheets; the tree shear buying guide explains how the current families are positioned. A used buyer needs the historic figures below and the inspection logic that follows.
What the published figures mean on site
Historic factory literature lists the six models as follows. Weights for WT005 and above are quoted “plus rotation configuration” because rotation was a build option that added materially to the head.
| Model | Published weight | Published maximum diameter | Indicative flow |
|---|---|---|---|
| WT002 | 340 kg | 150 mm | 50–60 L/min |
| WT004 | 430 kg | 150 mm | 50–60 L/min |
| WT005 | about 545 kg plus rotation configuration | 250 mm | 60–80 L/min |
| WT010 | about 980 kg plus rotation configuration | 350 mm | 80–100 L/min |
| WT015 | about 1,550 kg plus rotation configuration | 450 mm | 130–150 L/min |
| WT020 | about 1,835 kg plus rotation configuration | 500 mm | 150–180 L/min |
Three things about these figures matter to a buyer. First, the maximum diameters were published against the timber of the day and were never a production rating in Australian hardwood; a WT010 at 350 mm was a 200 to 250 mm production head in eucalypt for most owners. Second, the weights exclude rotation, bracket and hitch, so a WT015 as fitted could sit several hundred kilograms above 1,550 kg, and the figure that matters for the lift chart is the one you measure on a weighbridge, not the one in the brochure. Third, the flow bands are indicative and vary with production year, so a unit that closes slowly on a carrier inside the band may simply be worn rather than mismatched.
Carrier matching
Treat the roughly 5 to 35 tonne carrier span as a description of where these heads were fitted, not as a recommendation for any one of them. A used WT should be matched to your excavator exactly as a new head would be: measured configured weight subtracted from the over-side lift chart at the working radius, as the lift chart and attachment mass guide sets out, then flow and pressure confirmed against whatever build documentation the serial number turns up. The hydraulic matching guide lists the figures to gather. Older heads may use a different bracket standard, different hose sizes and different coupler practice from a current machine, and the cost of adapting all of that belongs in the purchase decision. Ask whether the original carrier pairing was sensible; a head that spent its life on an undersized machine has usually been overloaded.
Typical work and production considerations
The reason WT heads still change hands is that a well-kept one on a matched carrier does the same job it always did, and that job is the same as the current families’: regrowth, shelterbelt and orchard removal at the small end, road corridor and farm clearing in the middle, and subdivision and civil clearing at the top. The production logic is unchanged: price the site on the dominant stem size, not the brochure maximum. What is different is the risk. A used head’s actual cutting performance depends on blade profile, pivot wear and cylinder condition, and none of that is visible in a listing photograph. Insist on a live cutting test in timber of your typical size, not an open-and-close cycle in a yard.
Limitations and when to step up or down a size
The WT002 and WT004 share a 150 mm rating and are small-carrier heads for arborist and council work; the WT005 at 250 mm is the practical floor for farm and roadside regrowth. Above that, the same logic applies as in the current range: if most stems are below 250 mm a lighter head with quicker cycles wins, and if large stems are routine step to the WT015 or WT020 class or, more sensibly, to a new WR. Do not buy a WT020 for a 20 tonne machine on the strength of its 500 mm rating without doing the lift arithmetic with the real weight.
Options and configuration to settle at quotation
For a used unit the configuration is already decided; what you are settling is whether it is documented. Confirm the exact model and serial number with Machinery Specialist, whether rotation and any accumulator were fitted at build or added later, what bracket it carries and whether it will be included, and whether a compatible hitch adapter exists for your carrier. Any structural welding around the blade carrier or bracket should come with repair records or be priced as a risk.
Wear parts and support
This is where a WT purchase is won or lost. Before money changes hands, confirm with the distributor that blades, pins, bushes and cylinder seal kits are still available for that serial, and what the lead time is. Then inspect blade straightness, edge condition and any previous hard-facing, main pivot pins and bush play, cylinder rods and leakage, frame cracking, rotator play and leakage, hoses, bracket welds and accumulator arms. The used attachment inspection guide has the full checklist and the wear parts guide the consumables list.
Confirm before ordering
- Exact WT model and serial number confirmed with Machinery Specialist, not inferred from a listing
- Whether rotation and accumulator were factory fitted, and the measured configured weight including bracket
- Current availability and lead time of blades, pins, bushes and seal kits for that serial
- Original carrier pairing and any history of use on an undersized machine
- Lift-chart check on your excavator at working radius with the measured weight
- Flow and pressure requirement from build documentation, and bracket, hose and coupler compatibility with your carrier
- Repair records for any structural welding around the blade carrier, frame or bracket
- A live cutting test in timber of your typical size before purchase
Frequently asked questions
Why do Australian listings still say Trevi Benne makes six tree shear sizes?
Because the six-model WT range was the basis of older dealer marketing, and that wording has persisted. The current factory catalogue presents three WL and three WR models instead.
Can I still get blades for a WT head?
Availability varies by model and production year. Confirm with the distributor against the serial number before buying; parts for a common mid-range model are more likely than for an early small unit.
Are the weights in the table what my excavator will carry?
No. They exclude rotation, bracket and hitch. Weigh the head as fitted, or have the distributor confirm the configured weight, before checking the lift chart.
Is a WT020 equivalent to a WR20?
Only loosely. Both are the largest in their families, but the WR uses the current twin-blade Hardox system and factory-current options. Treat them as different products with different support positions.
Should I buy a used WT or a new WL?
If the WT is well documented, parts are confirmed and it passes a cutting test, it can be sound value. If any of those is missing, the price difference rarely covers the risk.
Get a recommendation, not just a price
Send us your excavator model, hydraulic figures, tree species and typical diameters. We will come back with a carrier-matched configuration and a written specification you can compare against any other quote.