Woodmaxx WM-8M 8-inch Mechanical-Feed PTO Woodchipper Review (2026)
8-inch mechanical self-feeding PTO chipper — the lowest-cost way into 8-inch capacity in the Woodmaxx line.
Woodmaxx WM-8M assembly and walkaround: 8-inch mechanical-feed PTO chipper
Manufacturer assembly and walkaround of the WM-8M covering the mechanical auto-feed roller, 8" capacity, and PTO driveline.
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- 8-inch capacity at mechanical-feed pricing
- Wide 25–70 HP tractor range
- Mechanical feed can stall on forked or crooked wood
- 3-year WM warranty vs 7-year MX
Mechanical feed is the whole story
The M in WM-8M stands for mechanical. There are no hydraulics on this chipper — the single 6.25-inch infeed roller is driven off the flywheel through a belt and gearbox, with about 165 lb of spring-loaded down pressure pulling material into the knives. On a clean straight 6-inch log, that's plenty. The chipper grabs the wood, pulls it in at roughly 58 ft/min, and turns it into chips without complaint. This is the experience Woodmaxx demos on YouTube and the experience owners describe when they're feeding from a tidy log pile.
The problem is real-world brush. Forked branches, Y-crotches, and crooked limby material that flares wider than the 8-inch infeed opening will hang on the single roller and stall the feed. There's no reverse. When that happens you shut the PTO, drag the piece back out by hand, rotate it, and try again. Mechanical-feed owners on TractorByNet describe needing to manually nudge irregular branches several times an hour. If your chip pile is mostly storm-drop yard cleanup, that's a workflow tax you'll pay every session.
WM-8M vs WM-8H: when the extra $400 pays off
The WM-8H is the same 8-inch capacity, same 3-year warranty, same physical size — with hydraulic dual feed rollers and a reverse lever instead of the single mechanical roller. It costs $4,095 versus the WM-8M's $3,690. Four hundred and five dollars buys you the ability to feed forked and crotchy material without babysitting, and a reverse function that lets you back out a jammed piece in two seconds instead of two minutes.
The math is simple — and at $405 the answer is almost always 'pay it.' If you chip mostly clean straight wood from a firewood operation or sawmill slabs, the WM-8M saves you a small amount and does the same job. If you chip yard brush, storm cleanup, or anything off a real tree with branches, the WM-8H pays for itself in saved hours within the first session. The WM-8M's case used to be a $800 savings story; with the gap now under $500, the WM-8H is the default recommendation for the overwhelming majority of buyers in this tier.
WM-8M vs MX-8600: capacity at a discount
The MX-8600 is Woodmaxx's MX-Series 6-inch chipper at $4,790 — actually $1,100 MORE than the WM-8M, despite being two inches smaller in capacity. The MX-Series premium buys you a 7-year transferable warranty (versus 3 years on the WM-Series), patented hydrostatic infeed with variable speed control, and a lower 15 HP minimum PTO requirement. You also give up two inches of capacity. That's the trade.
On paper this looks like an easy WM-8M win — more capacity, less money. In practice it depends on what you chip. If most of your material is under 6 inches, the MX-8600's hydrostatic feed handles forked yard brush the mechanical WM-8M can't, the 7-year warranty is real money over a decade, and the extra inches of WM-8M capacity sit unused. If you regularly chip 6–8 inch wood, the WM-8M wins on raw value and the MX-8600 is the wrong tool. The question for any WM-8M cross-shopper: how often are you actually chipping over 6 inches?
Cross-shop: Woodland Mills WC68
The closest cross-brand comparison at the 6-inch tier is the Woodland Mills WC68 — but the WC68 is now hydraulic-feed (Woodland Mills upgraded it), so it's not a direct mechanical-feed peer to the WM-8M. The WC68 is $3,450 MSRP (typically $3,105 on sale) with a 3-year warranty matching the WM-8M, 6-inch hydraulic-feed capacity. For buyers who specifically want a mechanical-feed PTO chipper because they prefer the simplicity, the WM-8M is now the cheapest name-brand mechanical-feed option in this capacity tier (the WC68 has moved upmarket). If you want hydraulic feed at the 6-inch tier instead, the WC68 is the value pick at $245 less than the WM-8M.
What's in the box
- WM-8M chipper unit
- PTO shaft with shear pin (540 RPM)
- Blade set (2 knives, installed)
- Mechanical self-feeding roller assembly (installed)
- 3-point hitch pins (Cat I / Cat II)
- Discharge chute
- Hardware bag
- Operator manual
- Tractor (25–70 HP with 540 RPM PTO)
- Quick-hitch adapter (if your tractor uses one)
- Ear protection and safety glasses
Ships freight on a pallet. Mechanical feed rollers are factory-installed. PTO shaft ships separately in the crate.
Woodmaxx WM-8M 8-inch Mechanical-Feed PTO Woodchipper specs at a glance
- Brand
- Woodmaxx
- Model
- WM-8M
- Power type
- pto
- Max branch diameter
- 8"
- Power
- PTO-driven, 25–70 HP tractor
- Feed system
- Mechanical self-feeding
- Weight
- 1150 lb
- Price (MSRP)
- $3,690
- Warranty
- 3 years
Will the WM-8M fit my tractor?
The Woodmaxx WM-8M 8-inch Mechanical-Feed PTO Woodchipper needs 25–70 PTO HP. Here’s how 26 common compact and utility tractors match up — rated PTO HP, not engine HP (after typical 10–15% drivetrain losses).
| Tractor | Engine HP | PTO HP | Hitch | WM-8M verdict |
|---|---|---|---|---|
| Kubota BX23S | 22 | 15 | Cat 1 | Too small |
| Kubota LX2610 | 25 | 19 | Cat 1 | Too small |
| Kubota L2501 | 24 | 19 | Cat 1 | Too small |
| Kubota L3301 | 33 | 26 | Cat 1 | Fits |
| Kubota L3901 | 37 | 30 | Cat 1 | Fits |
| Kubota L4701 | 47 | 38 | Cat 1 | Fits |
| Kubota MX5400 | 55 | 45 | Cat 2 | Fits |
| Kubota M4-071 | 70 | 58 | Cat 2 | Fits |
| John Deere 1025R | 24 | 18 | Cat 1 | Too small |
| John Deere 2025R | 25 | 19 | Cat 1 | Too small |
| John Deere 3025E | 24.7 | 19 | Cat 1 | Too small |
| John Deere 3032E | 32 | 25 | Cat 1 | Fits |
| John Deere 3039R | 38.2 | 30 | Cat 1 | Fits |
| John Deere 3046R | 45.3 | 37 | Cat 1 | Fits |
| John Deere 4044M | 43.1 | 35 | Cat 1 | Fits |
| John Deere 4066R | 65.9 | 53 | Cat 2 | Fits |
| Mahindra 1533 | 33 | 26 | Cat 1 | Fits |
| Mahindra 2638 HST | 37.4 | 29 | Cat 1 | Fits |
| Massey Ferguson 1735M | 35 | 28 | Cat 1 | Fits |
| Massey Ferguson 2705E | 49 | 40 | Cat 2 | Fits |
| New Holland WORKMASTER 25S | 24.7 | 18 | Cat 1 | Too small |
| New Holland WORKMASTER 35 | 35 | 28 | Cat 1 | Fits |
| Kioti CK2620 | 24.5 | 20 | Cat 1 | Too small |
| Kioti NX4510 | 45 | 38 | Cat 1 | Fits |
| LS MT225S | 24.4 | 18 | Cat 1 | Too small |
| LS MT342 | 41.3 | 32 | Cat 1 | Fits |
“Fits” = within the manufacturer’s rated PTO HP range. “At limit” = below the minimum by 5–15%, will feel underpowered on seasoned hardwood. “Too small” = undersized for reliable chipping. “Oversized” = above range (works but overkill).
Who should buy the WM-8M — and who should skip it
- You specifically need 8-inch capacity and won't accept stepping down to 6 inches
- You chip mostly clean straight wood — firewood lengths, mill slabs, or trunk sections without forks
- You want the cheapest entry price into a name-brand 8-inch PTO chipper
- You have a 30–60 PTO HP tractor and don't need the WM-8H's headroom
- You're comfortable manually working around the lack of reverse on jammed pieces
- You value Woodmaxx's US-based parts support over Woodland Mills' Canada-shipped service
- You chip yard brush, storm cleanup, or any material with forks and crotches — the WM-8H is only $405 more for full hydraulic feed
- You want the MX-Series 7-year warranty and don't need 8-inch capacity — the MX-8600 is the step-up (note: it costs $1,100 MORE than the WM-8M despite being 6-inch)
- You want reverse feed for safety and convenience — go WM-8H or MX-8800
- You actually want hydraulic feed at the 6-inch tier — the Woodland Mills WC68 ($3,450 MSRP, typically $3,105 sale) now offers hydraulic feed at $245 less than the WM-8M, with the same 3-year warranty
- Your tractor is under 25 PTO HP — the WM-8M will struggle, look at the MX-8500G+ ($2,990, 5-inch) instead
- You plan to run high annual volume — the 3-year warranty is the wrong tier for heavy use
Alternatives to the WM-8M
$305 more. same 8-inch capacity. adds hydraulic feed. from Woodland Mills.
$4,150 more. 7-inch capacity (1 inch smaller). 5-year warranty. from Wallenstein.
$240 less. 6-inch capacity (2 inch smaller). adds hydraulic feed. from Woodland Mills.
WM-8Maccessories & add-ons
Set of 2 replacement chipper knives for the WM-8M. Available from woodmaxx.com.
PTO shaft shear pins.
Replacement belt for the mechanical self-feeding roller system. Inspect annually for wear.
Upgraded PTO shaft for steep hitch angles.
WM-8Mblade replacement & sharpening
Two A8 flywheel knives on the 8-inch disc — larger and thicker than the MX-8600 stock.
Mechanical self-feed puts more load on the bed-knife gap: keep it set to 0.030–0.040" at reinstall, or the feed will stall on springy limbs.
- Blade count
- 2 flywheel knives
- Bed knife
- Yes — fixed anvil
- Sharpening angle
- 30–40°
- Reversible
- Yes — doubles edge life
- Blade material
- A8 tool steel
- Replacement set
- $160–$220
- Sharpening interval
- 25–40 hours
- Bolt torque
- 50–60 ft-lb
- 01Stop the machine and isolate power
Disengage the PTO, shut the tractor off, and remove the key. Wait 60+ seconds for the WM-8M flywheel to stop completely — it coasts longer than the engine.
- 02Open the discharge or flywheel access cover
Remove the bolts on the WM-8M flywheel access hood (or flip the hinged hood if equipped). Swing it clear so you have line-of-sight to every blade position.
- 03Rotate the flywheel to the first blade
Turn the flywheel by hand until the first of the 2 knives is aligned with the access opening. Mark it "1" with a paint pen so you can keep track of orientation.
- 04Break the blade bolts loose
Use a breaker bar on each of the 2 blade bolts. Woodmaxx and Woodland Mills both thread-lock these at the factory; heat gently if they don't yield. Do not pry on the flywheel itself.
- 05Slide the blade out and inspect
Remove the blade and inspect for cracks, nicks deeper than 1/16", and rounded bevels. A cracked blade goes straight in the scrap bin — never re-sharpened.
- 06Flip or replace the blade
The WM-8M uses 2 reversible knives. If the secondary edge is still clean, simply flip the blade for a fresh edge. If both edges are worn, sharpen at 30–40° on a belt sander — quench every 10–15 seconds to avoid bluing the A8 tool steel.
- 07Balance the set
Remove equal material from every blade in the set. On the WM-8M's 2-knife flywheel, even a 1–2 gram imbalance shows up as vibration at operating RPM. Weigh on a gram scale after sharpening.
- 08Reinstall and torque
Apply anti-seize to the bolt threads (not the heads) and torque in a star pattern to 50–60 ft-lb. Use fresh lock washers — reused washers are the #1 cause of a loose blade downstream.
- 09Repeat for every remaining blade
Rotate the flywheel and repeat steps 3–8 for the remaining 1 knives. Then inspect the fixed bed knife — if the edge is rounded, flip or replace it and reset the blade-to-anvil gap to ~0.030" with feeler gauges.
- 10Close up and test-run
Rotate the flywheel by hand one full revolution to confirm no contact with the bed knife or housing. Close the access cover. Start the tractor, engage PTO at low idle, and listen for 30 seconds before ramping to operating RPM. Feed one small test branch before returning to normal work.
WM-8M — frequently asked questions
- Can the Woodmaxx WM-8M handle forked or crooked branches?
- Not well. The single mechanical infeed roller relies on gravity and 165 lb of down pressure to pull wood through. Forked Y-crotches and crooked limby material hang up on the roller and stall the feed. There's no reverse, so you'll need to shut the PTO, pull the piece out by hand, rotate it, and try again. For irregular branch material, the hydraulic-feed WM-8H is the right machine.
- Why is the WM-8M warranty only 3 years when the MX-8600 has 7?
- The WM-Series is Woodmaxx's mid-tier line with a 3-year parts warranty. The MX-Series is the premium tier with 7-year transferable coverage and upgraded feed components. The warranty difference reflects build tier, not a defect — but it's a real factor in long-term value. A 7-year MX-Series warranty effectively covers most failure modes; the 3-year WM-Series window expires while the chipper is still middle-aged.
- When does the WM-8M actually win versus the WM-8H?
- Narrow cases: you almost exclusively chip clean straight wood (firewood operations, sawmill slabs, lengths cut from clear trunks) and the $405 saving over the WM-8H actually matters. With the gap that small in 2026, the WM-8H is the easier call for the overwhelming majority of buyers. The WM-8M's only structural advantage is simpler mechanical hardware to maintain — no hydraulic pump, no reservoir.
- Will the WM-8M chip knotty hardwood at 8-inch capacity?
- Yes if your tractor has the horsepower. The published 25–70 PTO HP range chips full 8-inch material when you're above roughly 50 PTO HP. Under 35 PTO HP, expect to slow down on seasoned 8-inch hardwood — the feed will hesitate even on straight stock. Knots themselves chip fine; the limitation is sustained torque, not knot resistance.
- Is the WM-8M the same as the older Woodmaxx 8M?
- Yes — Woodmaxx renamed the original 8M to WM-8M when they introduced the MX-Series naming. Older TractorByNet threads about the 8M describe the same machine. The chipper has had minor running changes (clutch adjustment, infeed roller updates) but the core mechanical design is unchanged.
- Can you add hydraulic feed to a WM-8M later?
- No. The WM-8M and WM-8H are different chassis. There's no upgrade path — the hydraulic version has dual rollers, a self-contained hydraulic pump and reservoir, and a different infeed housing. If you think you might want hydraulics within a few years, buy the WM-8H now; the resale gap between the two used will be larger than the $800 price difference new.
- WM-8M vs wm-8h difference — which should I buy?
- See our head-to-head comparison for the detailed breakdown. In short: the WM-8M at $3,690 offers 8-inch capacity with mechanical self- feed. The right pick depends on your tractor HP, branch size, and whether you need hydraulic feed for forked material.
- Will the WM-8M work on a kioti 2610?
- Check your tractor's rated PTO HP (not engine HP). The WM-8M needs 25–70 PTO HP. Most kioti 2610 tractors produce enough PTO HP, but verify your specific model's PTO output in the owner's manual. Also confirm your 3-point hitch lift capacity can handle 1150 lb. See our tractor compatibility table above for 26 common tractor models.
- How hard is the WM-8M to assemble?
- The WM-8M ships approximately 90% assembled. You'll attach it to your tractor's 3-point hitch, lower the infeed bin, raise the discharge chute, size and attach the PTO shaft (included), and grease the bearings. Typical setup time: 30–60 minutes with basic tools.
- WM-8M vs mx-8600 — which should I buy?
- See our head-to-head comparison for the detailed breakdown. In short: the WM-8M at $3,690 offers 8-inch capacity with mechanical self- feed. The right pick depends on your tractor HP, branch size, and whether you need hydraulic feed for forked material.
- How much HP do I need to run the WM-8M?
- The WM-8M needs 25–70 PTO HP. That's PTO horsepower (roughly 85–90% of engine HP). A 29 HP engine tractor produces about 25 PTO HP. Comfortable range: 31–63 PTO HP.
- What warranty does the WM-8M come with?
- Woodmaxx covers the WM-8M with a 3-year warranty. Covers manufacturing defects; excludes wearing parts and cosmetic damage.
- What can the WM-8M actually chip in real-world use?
- Rated for 8-inch branches. In practice, green softwood chips reliably at rated max. Seasoned hardwood at 8 inches slows the feed rate and bogs the flywheel on knots — comfortable working capacity on hardwood is 6.5–7.5 inches. The mechanical feed handles straight material well but can stall on forked branches.
- Is the WM-8M worth buying?
- At $3,690, the WM-8M is the value sweet spot — enough capacity for regular property use without commercial pricing. The 3-year warranty is shorter than competitors — factor that into your decision.