We have been getting a lot of requests to have the DIY Kits installed and transmissions built at Spool Performance and we are listening and adding that option for everyone. 

This listing includes parts and labor for overhauling a ZF8HP 70/75 in good working condition into a Spool Stage 2 Transmission Build. 

If the core supplied is not in good working order, the core will be examined, and damaged parts in your core will be communicated to you. Necessary replacement parts will be billed separately.

Note: Freight shipping to and fro will be arranged by the customer. If you need assistance with shipping please call our office.

Spool Performance Stage 2 Transmission Kit for Dodge 8HP70 & 8HP75

After over a year of rigorous engineering and validation, Spool Performance proudly introduces the Stage 2 Transmission Upgrade Kit for the Dodge 8HP70 and 8HP75 platforms. Designed to far exceed the limitations of factory components, this kit delivers well over 1200 ft-lbs of torque capacity while retaining excellent drivability and shift quality.

This upgrade lets you hold way more torque than a stock 8hp90 from a hellcat reliably without having to go through the struggles of programming and swapping transmissions and is good for upwards of 1200whp.

Each kit features our in-house–developed FX-RT friction system, billet 7075-T6 heat-treated and hard-anodized C and E hubs, redesigned pressure and apply plates, and increased clutch counts across every clutch pack for unmatched clamping force and thermal stability. This package transforms the 8HP70/75 into a transmission capable of handling the abuse of high-boost HEMI builds, drag launches, and elevated power levels.

Advanced Billet Hub Engineering

The OEM C and E hubs in the 8HP series are made from weak cast A380 aluminum and are well-known failure points in tuned Dodge vehicles. Under high torque, these hubs frequently experience:

• Spline shearing

• Cracking at the locking features

• Steel plates digging into the soft aluminum, causing binding, slip, or total burnout

Key Spool Hub Upgrades

• Material Upgrade:
  Manufactured from aerospace-grade 7075-T6 billet aluminum, offering near-steel strength at a fraction of the weight.

• Treatment:
  Heat-treated and hard-anodized, dramatically improving surface hardness, wear resistance, and long-term spline integrity.

• Design Enhancements:

  • Optimized clutch cooling paths

  • Faster oil evacuation

  • Increased clutch contact area

  • Reduced rotating mass for sharper shift response

These improvements eliminate the weak points of the OEM hubs while significantly enhancing performance under sustained high load.

FX-RT High-Coefficient Frictions + Increased Clutch Counts

Our FX-RT friction technology, originally engineered for the highest-torque Mercedes 9G and BMW 8HP platforms, is now optimized for the Dodge 8HP70/75. These friction materials deliver:

• Considerably higher friction coefficients than OEM

• Superior thermal resistance under repeated high-load shifts

• Stable, consistent engagement without harshness

• Exceptional durability on boosted, nitrous, and high-RPM HEMI builds

Each clutch pack — A, B, C, D, and E — receives increased clutch counts, providing more friction interfaces for greater torque handling and cooler operating temperatures.

This combination of FX-RT materials and added clutch capacity results in a transmission that can confidently hold torque levels well beyond the capability of a stock 8HP70/75.

Features Overview

• FX-RT High-Coefficient Frictions: In-house developed, high-energy material for maximum holding power.

• Billet 7075-T6 Hubs: Heat-treated and hard-anodized for superior strength, rigidity, and wear resistance.

• Increased Clutch Counts: Every clutch pack receives added frictions and steels for enhanced torque capacity.

• Custom Pressure & Apply Plates: Provide optimized clamping force and ideal shift characteristics.

• Pre-Clearanced Clutch Packs: Ready to install, eliminating setup guesswork.

• Extra Steel Plates: Included for optional custom clearance adjustments.

What’s Included

• 7075 Billet E Hub

• E Hub Center Bushing

• 7075 Billet C Hub

• A Clutch: Frictions, Steels, Pressure Plate, Apply Plate

• B Clutch: Frictions, Steels, Pressure Plate, Apply Plate

• C Clutch: Frictions, Steels, Pressure Plate

• D Clutch: Frictions, Steels, Pressure Plate, Apply Plate

• E Clutch: Frictions, Steels, Pressure Plate

• Complete Seal Kit (Gaskets + O-rings)

Compatibility: Dodge / RAM / Jeep / Chrysler 8HP70 & 8HP75 Platforms

Dodge

• Charger R/T 5.7

• Charger Scat Pack / SRT 392 6.4

• Challenger R/T 5.7

• Challenger Scat Pack / SRT 392 6.4

• Durango R/T 5.7

• Durango SRT / 6.4L

RAM

• Ram 1500 5.7 (DT, 8HP75)

• Ram 1500 3.0 EcoDiesel

• Ram 2500 / 3500 6.4 (8HP75-LCV)

Jeep

• Grand Cherokee 5.7

• Grand Cherokee SRT 6.4

• Grand Cherokee 3.0 EcoDiesel

• Wrangler 392 6.4

• Wagoneer / Grand Wagoneer (8HP75 variants)

Chrysler

• 300C 5.7

• 300 SRT 6.4