2026 Hennessey Mammoth 1000 — Specs, Price & Review

Overview

The RAM 1500 TRX arrives from the factory as the most powerful production pickup in America at 702 hp. Hennessey takes it to 1,012 hp with a Whipple 3.0L supercharger upgrade, high-flow injectors, an intercooler, and a full recalibration. The result is the Mammoth 1000 — a name that understates nothing.

Zero to sixty in 3.9 seconds from a full-size pickup truck that can still tow 8,000 lbs and carry 1,300 lbs of payload. The Mammoth runs the quarter mile in 11.5 seconds at 121 mph — faster than most sports cars and virtually all trucks. Hennessey's ECU calibration is conservative enough for daily driving while delivering the full 1,012 hp when demanded.

Every Mammoth 1000 receives a serialized Hennessey dash plaque, Hennessey exterior badging, and is registered in Hennessey's official registry. The RAM TRX platform is retained in its entirety — four-wheel drive, electronic lockers, 13-inch front/14-inch rear Bilstein bypass shocks, 35-inch BF Goodrich tires — all factory RAM TRX systems remain functional and warranted.

Specs & Trims

Trims & Pricing

Prices are MSRP before destination, taxes and fees. Verify at manufacturer website.

Configuration

Mammoth 1000

$149,000

1,012 hp on TRX platform, serialized

Supercharged 6.2L Hellcat Redeye V8

Configuration

Mammoth 1200

$195,000

1,200 hp ultra package, additional cooling

Further-upgraded supercharger and fueling

Prices as of June 2026. Destination ~$1,495–$2,000 additional.

Full Specifications

Specification	Detail
Base Vehicle	RAM 1500 TRX
Supercharger	Whipple 3.0L positive displacement
Horsepower	1,012 hp
Torque	969 lb-ft
0-60 mph	~3.9 seconds
Quarter Mile	11.5 sec @ 121 mph
Towing	8,000 lb rated
Payload	1,300 lb
Built	Sealy, Texas — Hennessey Performance

Source: Hennessey media. Verify all specifications at manufacturer website before purchasing.

Reliability

Independent Research

Consult Consumer Reports and J.D. Power. Check all open recalls at nhtsa.gov/recalls before purchasing any used vehicle.

Component	Status	Notes
Supercharger	Excellent	Whipple proven in truck applications
TRX Platform	Excellent	RAM's factory TRX suspension and 4WD retained fully
Cooling	Good	Intercooler upgrade included; monitor engine temps in summer
Overall	Excellent	Hennessey's conservative tune ensures daily drivability

Recalls & VIN Check

NHTSA Database

Check Open Recalls Before Any Purchase

Recall status changes. Verify your specific VIN at nhtsa.gov — not just the model year.

📋 VIN Decoder & Recall Check

→ Check on NHTSA.gov

Enter your 17-digit VIN above to decode and check open recalls.

Costs & Comparison

Ownership Costs

Mammoth 1000 ownership runs $149,000 all-in. Insurance averages $3,500–$5,500. The TRX base means comprehensive RAM dealer support for base vehicle components. Hennessey supercharger components require Sealy service — plan annual visits.

vs. The Competition

Cross-shop these direct alternatives before finalizing your purchase decision.

Competitor	Base MSRP	Key Consideration
RAM TRX stock	Verify	Mammoth at $149,000 vs RAM TRX at $93,000 vs Raptor R at $109,145.
Ford Raptor R	$109,145	Raptor R wins on off-road capability.
Shelby F-150	$39,330	Mammoth wins on straight-line performance.

Buying Guide

Buying Guide & Who Should Buy

Research current incentives and compare against cross-shop alternatives before purchasing. Verify current pricing, availability, and specifications at the manufacturer's website. Test drive multiple trims to determine the right configuration for your specific needs.

Heritage & History

The Hennessey Mammoth represents an important model in American automotive history with a loyal ownership community. Consult manufacturer history and automotive press archives for comprehensive heritage information.

Pros & Cons

Strengths

1,012 hp from a full-capability pickup truck — nothing else comes close

Full TRX platform retained — 4WD, lockers, long-travel suspension all work

Hennessey registry and serialization add collector documentation

Quarter mile at 11.5 seconds proves the performance is real and verified

Available with 1,200 hp upgrade for buyers who need even more power

Weaknesses

$149,000 total cost is substantial for a pickup truck, a real consideration when cross-shopping less expensive alternatives

1,012 hp with TRX fuel economy: expect 8-10 mpg in mixed driving

Hellcat Redeye V8 at this power level requires premium fuel always

Hennessey service is concentrated in Texas

Tire wear accelerates significantly with regular performance driving

Fully loaded configurations can exceed $80,000, well above the advertised starting price

Fuel economy trails smaller trucks and crossovers meaningfully, especially with larger engines

Frequently Asked Questions

Does the RAM warranty cover the Mammoth 1000 modifications?

RAM's factory warranty covers base TRX components that Hennessey has not modified. Hennessey provides their own warranty on all installed components. Hennessey's relationship with RAM allows them to preserve as much factory coverage as possible.

How does the Mammoth 1000 compare to the stock TRX?

The TRX makes 702 hp stock; the Mammoth 1000 makes 1,012 hp — a 310 hp increase. Both use the same Hellcat Redeye V8 block. Hennessey's supercharger swap adds the power while the TRX's long-travel suspension, electronic lockers, and 4WD remain completely factory.

Can the Mammoth 1000 tow a trailer?

Yes — towing capacity is rated at 8,000 lbs, consistent with the base TRX. Hennessey has validated towing performance at the modified power levels. The additional power provides more reserve when towing at highway speeds in hills.

What octane fuel does the Mammoth 1000 require?

93 octane minimum. The Hellcat Redeye V8 at 1,012 hp requires premium fuel for optimal performance and engine protection. Using 87 octane will cause significant knock retard and reduce power substantially.

Is the Hennessey Mammoth available new from a dealer?

Hennessey partners with select RAM dealers to sell the Mammoth 1000 as a factory-authorized build. It can be purchased as a complete vehicle through the dealer finance process. Check hennessey.com for authorized Mammoth dealers.

What is the Mammoth 1000's top speed?

Hennessey estimates the Mammoth 1000 is capable of 150+ mph. The electronically limited TRX top speed is 118 mph; Hennessey recalibrates this limit as part of the build. Highway driving at those speeds in a truck is not recommended.

Does the Mammoth come with a warranty?

Hennessey provides a 3-year/36,000-mile warranty on all Mammoth-installed components. This covers the supercharger, intercooler, fuel system upgrades, and ECU calibration.

How long does the Mammoth 1000 build take?

Hennessey typically completes the Mammoth 1000 build in 4-6 weeks from receipt of the base TRX. Customers can purchase through a dealer and have the vehicle shipped to Sealy, Texas for conversion, or buy a pre-converted unit from Hennessey inventory.

Hennessey Mammoth 1000 Accessories & Upgrades

Car Cover

All-weather outdoor storage protection.

Shop Amazon

Cargo Organizer

Collapsible trunk storage for gear and groceries.

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Phone Mount

Wireless charging dash and vent mount.

Shop Amazon

Amazon affiliate links — small commission at no extra cost to you. Disclosure.

Sources & References

Hennessey Performance hennessey.com
RAM Trucks ramtrucks.com
NHTSA nhtsa.gov
Motor Trend

AmericanCarBrands.com is independent editorial research — not affiliated with Hennessey. All prices as of June 2026. All trademarks are property of their respective owners.

Mammoth 1000

Overview

Specs & Trims

Trims & Pricing

Full Specifications

Reliability

Reliability

Recalls & VIN Check

📋 VIN Decoder & Recall Check

Costs & Comparison

Ownership Costs

vs. The Competition

Buying Guide

Buying Guide & Who Should Buy

Heritage & History

Pros & Cons

Frequently Asked Questions

Best of 2026 — Research Guides