Grilla Grills Mammoth Review: 1,660 Square Inches of Insulated Cabinet

The Grilla Grills Mammoth is built to answer a question barrel-style pellet grills answer badly: how do you smoke a lot of food at once without giving up half your patio? Its answer is a tall, double-walled cabinet with 1,660 square inches across five stainless racks and a 40 lb hopper Grilla claims will run more than 50 hours at 250°F. It is the insulated pick in our best vertical pellet smoker roundup and a value pick in best pellet grills under $1,500, and until now it has not had a review page of its own.

This review is research-based, as all of ours are. We work from Grilla's published specifications, from the Amazon listing we resolve and verify through the Amazon Creators API, and from the independent long-form reviews that exist on the model — most usefully Smoked BBQ Source's, whose reviewer cooked on the unit for weeks. We have not cooked on this smoker ourselves and we are not going to pretend otherwise. What we can do is report the specs accurately and be straight about the flaws, including the two that no spec sheet shows: it is loud, and it has no handle.

Who It's For

The Mammoth is for the cook whose constraint is quantity, not capability. If you make sausage in batches, run jerky in volume, cook eight pork butts for a party, or smoke through January without wanting to think about the weather, this is the right shape of cooker and the insulation is the reason.

It is not a first grill. There is no direct-flame zone, the ceiling is 450°F, and no amount of technique will produce a seared steak or crisp chicken skin inside an enclosed cabinet. The Mammoth assumes you already own something that grills — a gas grill, a griddle, or a barrel pellet grill with a sear function — and it specializes instead. If you want one cooker that does everything, our best pellet grills roundup is the right starting point, and our pellet grill sizing guide will tell you whether you are actually in cabinet territory.

Key Features

• 1,660 square inches across five stainless steel racks (about 332 sq in each) inside roughly 6 cubic feet of cabinet, with ten rack positions so you can space the racks to the cook.
• Expandable to roughly 3,300 square inches with five accessory racks, sold separately.
• Double-wall insulated construction — the specification that separates this from every budget vertical.
• 40 lb hopper with a Grilla-claimed 50-plus hours of burn time at 250°F from one fill.
• Alpha Connect 2.0 controller: PID temperature control, color capacitive-touch screen, WiFi and app control.
• 180°F to 450°F in 5-degree increments. Below 180°F the controller enters a low-temperature shutdown mode.
• Two meat probes and two probe ports included.
• Lipped heat diffuser that accepts wood chips or chunks for extra smoke, plus an integrated water pan for moisture and low-temperature stability.
• Stainless hanging rack with 24 S-hooks in the box — the practical way to hang snack sticks and kielbasa.
• 59" H x 28" W x 28" D, about 130 lb, with a 4-year warranty per Grilla's product page.

Specs: Mammoth vs the Verticals It Competes With

The trade reads clearly off that table. The Mammoth costs roughly double a Pit Boss cabinet and gives you insulation, a bigger hopper, a true PID controller and a build quality independent reviewers rate highly. The Pit Boss cabinets give you a lower 130°F floor — which genuinely matters for jerky — a longer warranty on paper, and most of the rack space for half the money. Our best vertical pellet smoker roundup runs all of them side by side.

Performance: What the Specs and Independent Reviews Say

Temperature stability. This is where the double wall pays. The Smoked BBQ Source reviewer specifically credited the insulation with holding temperature through long cooks, and noted a heavy-duty door latch with almost no smoke leakage — the two things that determine whether a cabinet actually behaves like an oven. A PID controller on an insulated box is a genuinely different experience from a cycling controller on a single-wall one, and if you have fought pellet grill temperature swings on a thin-skinned cooker, this is the structural fix.

Fuel economy. Grilla claims 50-plus hours at 250°F from a 40 lb hopper, which works out to well under a pound an hour. Manufacturer burn-rate claims are always best-case, but the independent number is encouraging: after a 20-to-22-hour cook at 225°F, the Smoked BBQ Source reviewer reported roughly half the pellets remaining. That is the insulation showing up on the receipt. For context on what a single-wall grill costs to run, see how many pellets does a pellet grill use.

Smoke and bark. Vertical cabinets are efficient smoke producers because the food sits in a tall column of rising smoke, and the Mammoth adds a lipped heat diffuser that takes wood chips or chunks on top for more. The Smoked BBQ Source reviewer reported strong bark and smoke flavor on pork butts and a pulled ham. Pellet choice still does more work here than the cooker does — our best wood pellets for pork rankings cover which woods suit which cuts.

What it cannot do. 450°F in an enclosed cabinet with no flame path is roasting heat. No sear, no grill marks, no crisp skin. Grilla does not claim otherwise, and we would rather you read it here than discover it on a steak. If searing matters, our best pellet grill for searing roundup covers the grills built for it.

Cold weather. This is the Mammoth's home ground. A double-walled cabinet is the correct tool for winter smoking and the reason we rank it as the insulated pick. Our cold-weather pellet grilling guide explains why chamber construction matters more than controller quality once the temperature drops.

The Honest Flaws

A spec sheet will not tell you any of this, and all of it comes from the independent review record rather than from Grilla.

It is loud. The Smoked BBQ Source reviewer described it as running noticeably loud — audible from inside the house. Vertical cabinets use a combustion fan to push heat up a tall column, and that fan works harder than one in a barrel grill. If your patio sits under a bedroom window, factor it in.

There is no handle. 130 pounds, no carry handle, four legs. Assembly is reportedly easy — about 30 minutes, mostly attaching legs to the body — but repositioning the assembled smoker is a two-person job and not a casual one. Decide where it lives before you build it.

No cover is included. Grilla sells one separately and offers a cover bundle on its own site. An uncovered insulated cabinet left in the weather is a bad trade on a four-figure cooker, so budget for it — our pellet grill cover buying guide covers what matters in one.

The app did not connect for at least one reviewer. Smoked BBQ Source could not get the Grilla app onto WiFi, while suspecting their own network. We cannot resolve that from the outside, and WiFi is the single most-complained-about feature across every pellet brand — our Traeger WiFi troubleshooting guide exists for the same reason. Buy the Mammoth for the cabinet, not the app.

There was a documented factual correction in the review record. The Smoked BBQ Source review originally stated that wood chunks had to be added through the bottom cabinet; a reader and Grilla's own team noted they can be added on top of the heat deflector, and the publisher said the review would be updated. We mention it because it is the better instruction and because it shows how new this cabinet still is to the reviewing world.

Ownership Notes

• Burn it off before the first cook. The Mammoth needs a seasoning burn-off before you put food in it, the same as any new pellet cooker. The routine is the same as our first cook on a pellet grill guide describes.
• Clean the ash roughly every 24 hours of cook time. That is the figure from the independent review, and it is the one maintenance item with a real failure mode behind it — see pellet grill grease fire for why it matters.
• Use the hanging rack. 24 S-hooks and a stainless hanging rack are included, and hanging is simply the better way to run snack sticks, kielbasa and jerky. Grilla's own capacity figures quote 250 feet of snack sticks and 95 lb of summer sausage.
• Use the water pan on long cooks. It is standard equipment here and it does two jobs: moisture, and thermal ballast that steadies the cabinet at low set temperatures.
• Store the 40 lb bags properly. A cabinet with a 40 lb hopper encourages buying pellets in bulk, and bulk pellets go bad in damp garages. How to store wood pellets covers the routine.
• Measure the doorway, not just the patio. 59 inches tall, 28 inches square, 130 lb assembled.

Price and Where to Buy

Pricing on the Mammoth is worth checking in two places, and we will be plain about it: when we checked in October 2026, Grilla's own site listed the base Mammoth below the Amazon listing we track, with cover and starter-kit bundles above it. Amazon is the only retailer we link, so the button below carries the live tracked Amazon price rather than a number typed into this page — but if you are buying a cooker in this bracket, spend two minutes comparing it against Grilla direct before you order. Buying it cheaper somewhere we do not earn on is still the right call for you, and we would rather say so.

For where that lands against the rest of the market, the Mammoth is one of the picks in our best pellet grills under $1,500 roundup, where it is the only insulated cabinet on the page.

Verdict

The Grilla Grills Mammoth earns a 4.5 out of 5 from us, and the score reflects a cooker that is unusually clear about what it is. On the two things that define a vertical pellet smoker — rack space and insulation — it is the best answer in its price bracket, and the 40 lb hopper plus a PID controller means an overnight cook genuinely runs unattended in a way a single-wall cabinet's does not. The independent review record backs that up: steady temperatures, almost no smoke leakage, half a hopper left after twenty-plus hours, and bark worth the trouble.

What keeps it off a perfect score is honest and mostly unfixable. It is loud. It weighs 130 pounds and has nothing to grab. It cannot sear, which means it is a second cooker for most people rather than a first. The warranty is four years when cheaper grills offer five. And it costs roughly double a Pit Boss vertical that will smoke a perfectly good pork butt.

So buy it for volume and for winter. If you smoke weekly, make sausage, run overnight cooks, or live somewhere the thermometer takes January seriously, the insulation and the hopper are worth the premium and you will notice them every cook. If you smoke six times a year in mild weather, buy a single-wall cabinet and spend the difference on pellets and a wireless thermometer — you will not out-cook the Mammoth, but you will not miss it either.

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Explore more: Best Vertical Pellet Smoker | Best Pellet Grills Under $1,500 | Best Wood Pellets for Pork | Pellet Grill Cold Weather Guide | Pellet Grill Warranty Comparison | What Size Pellet Grill Do I Need | All Reviews