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The Transmission Report is a free, 8-page newsletter featuring exciting new Sonnax products, in-depth tech articles with valve body diagnostics, rebuilding tips and tricks from the pros, special case studies and more. This valuable newsletter is mailed three times a year to U.S. residents, and can also be read online.

Continental U.S. only.


Newsletter Archive

December, 2023

Transmission Report Newsletter: December 2023

Featured in this issue:

  • New Sure Cure & 10-Speed Valve Repairs
  • Rostra OEM/S Parts Announcement
  • 6L80 Lube Dam Tech Tip for Easy Repairs
  • ZF8 Separator Plate Identification
  • New 6R80, ZF6 Heavy Duty OD “E” Piston
  • Tech Tip: Choose the Right AODE, 4R70W Bypass Clutch Control Valve Repair
Read Online
July, 2023

Transmission Report Newsletter: August 2023

Featured in this issue:

  • 8L45/90 Signal Accumulator Piston Updates & New Shuttle Valve Kit Options
  • New 9T45 Drop-in Valve & Pump Body Repairs
  • New 68RFE & 6L80/90 L/R Sprag Rebuild Kits
  • New 6R60/75/80 Center Support Snap Ring
  • New 4L60-E & 4L80-E Heavy Duty Upgrades
Read Online
March, 2023

Transmission Report Newsletter: March 2023

Featured in this issue:

  • New 6L80/90 Remanufactured TEHCMs
  • New Ford, GM & ZF Parts to Help Keep the Comebacks Away
  • Rostra Powertrain Controls: New Solenoids, Sensors & More
  • Tech Tip: Ford 10-Speed ATF Venting & Overheating
Read Online
December, 2022

Transmission Report Newsletter: December 2022

Featured in this issue:

  • Powertrain Expo & SEMA Photo Recap
  • New 4L60/E Servo Ratio Options & Housing Upgrade
  • New Chrysler & ZF8 Parts
  • New 10-Speed Vacuum Test Guide
  • New TH400 Drag Racing Drum Upgrade
Read Online
August, 2022

Transmission Report Newsletter: August 2022

Featured in this Issue:

  • 8L90 2019 Model Year Tech Alert
  • 68RFE Gear Upgrades & Piston Install Tip
  • 4L60-E, 4L65-E Heavy Duty Remanufactured Valve Bodies
  • 948TE Valve Body Repairs & ID Guide
  • Rostra 6R80, 6R100, 6R140 Solenoids
  • Ford/GM 10-Speed Solenoid Stabilizer
Read Online
April, 2022

Transmission Report Newsletter: April 2022

Featured in this Issue:

  • Sonnax Top Shop Products of 2022
  • AS66/69RC Valve Body Components
  • TH400 & 4L80-E Performance Upgrades
  • Ford 9" Pinion Yokes & 6R80 Bushings
  • Tech Tip: Easy 6L80 PR Valve Pump Drilling
Read Online
November, 2021

Transmission Report Newsletter: November 2021

Featured in this Issue:

  • Rostra Joins Sonnax Transmission Company

  • New Work/Sport Performance Upgrades

  • GM 8L45, 8L90 Valve Body Repairs

  • GM 6L45/50, 6L80/90 Bushings

  • New Pressure Switch Rebuild Options for GM 6-Speed TEHCMs

Read Online
July, 2021

Transmission Report Newsletter: July 2021

Featured in this Issue:

  • 68RFE Upgrades & Accumulator Piston Options You Need to Know About
  • New 8L45/90 Drop-In Zip Valves
  • New Parts for Faster, Easier, More Reliable 6L80, 62TE & 6F35 Builds
  • 1000+HP Rated Input Shaft for 4L80-E
  • Get Great Deals on Vacuum Test Equipment
Read Online
March, 2021

Transmission Report Newsletter: March 2021

Featured in this issue:

  • Resolving RFE Stalling & Overheat Issues After Performance Tuning
  • Announcing the Sonnax Fan Store
  • Gen. 3 6T40 Drop-In Pump Repairs
  • RFE, 48RE & 4L80-E Upgrades
  • Tech Team Tip: Drilling GM 6-Speed Pumps
Read Online
October, 2020

Transmission Report: Sonnax Announces Tool Shop & Zip Valves

Featured in this issue:

  • Introducing the Sonnax Zip Valve™
  • Great New Prices on Sonnax Tools
  • New 6-Speed Remanufactured Valve Bodies
  • 6R80, 6R100 Zip Kit® & Unit ID Guide
  • New Bushings, Bearings & Performance Parts for Better Builds
Read Online
March, 2020

Transmission Report Newsletter: April 2020

Featured in this issue:

  • 6L80/90 Transmission Tech Advisory: Consider an Updated Converter
  • Sonnax Hauls in Top Products & Tools!
  • Gen. 3 6T40 Units: What’s Changed & What’s Stayed the Same
  • Big Units Don’t Have to Mean Big Costs with AS66/69RC Valve Kits
  • Quickly & Easily Repair the Chrysler Solenoid Switch Valve
  • Conquering the GM Compensator Clip Conundrum

Read Online
January, 2020

Transmission Report: RFE Transmission Universal Valve Bodies: One SKU Does It All!

Featured in this issue:

  • New RFE Universal Valve Bodies: One SKU Does it All!
  • Must-Have 4R70W Series Upgrades for Work & Sport
  • Get Your Racers Ready for Their Best Season EVER!
  • JF016E (RE0F10D), JF017E (RE0F10E) Valve Body Components
  • Genuine OE, Direct Replacement Bearings
  • Full Line of ZF 6-Speed Precision Bushings
Read Online
October, 2019

Transmission Report: Unbeatable Protection Against 3-5-R Failures with 6T40 & 6T70 Drum Saver Kits

Featured in this issue:

  • Unbeateable Protection Against 3-5-R Failures with 6T40 & 6T70 Drum Saver Kits
  • New Parts for Jatco/Nissan JF015E Units
  • Must-Have Chrysler RFE Upgrades
  • New Solution for Forward & Reverse Delayed Engagement & Clutch Distress in the 4L60-E
  • GM Gen. 2 6T70, 6T75 & 6T80 Valve Body Layout & Components
  • Tech Tip: Protecting Your Shift Timing in GM 700R4 Applications
  • Hard-Working AS68RC Dodge Trucks Need Hard-Working Parts
Read Online
May, 2019

Transmission Report: Your Rebuild Is More Than The Sum of Its Parts

Featured in this issue:

  • Your Rebuild is More than the Sum of its Parts
  • An Important Change to Sonnax Packaging
  • Revolutionary AODE, 4R70W Upgrade Eliminates Direct Drum Problems
  • GM Gen. 1 6T70/75 Valve Body Components
  • Sonnax Earns Four Top Product Awards
  • Tech Tip: How to Properly Install 4L60-Series Wide Reaction Sun Gear Bushing
Read Online
November, 2018

Transmission Report: U150 2-3 Upshift Complaints & Solutions

Featured in this issue: 

  • U150 2-3 Upshift Complaints & Solutions
  • Must-Have Upgrades for AS68RC
  • A New 4-3 Sequence Valve Option for the 4L60-E
  • Introducing the Sonnax Research & Development Center
Read Online
July, 2018

Transmission Report: Introducing Premium GM 6L80 Series Remanufactured Valve Bodies

Featured in this issue:

  • Introducing Premium GM 6-Speed Remanufactured Valve Bodies
  • Product Development Takes the Spotlight at TASC Meeting
  • Meet Sonnax's New President
  • Great New Upgrades for AS68RC, 68RFE & 5R110W
Read Online
February, 2018

Transmission Report: How Small Changes Led to the New Form & Function of Gen. 2 6T70/75 Valve Bodies

Featured in this issue:

  • Small Changes Make a BIG Difference for GM 6T70/75 Gen. 2 Units
  • Outsmart OD Roller Clutch Failure with the Smart-Tech® Overrun Clutch Valve Kit
  • 6F35 Zip Kit® for Gen. 1 & 2 Units
  • Tech Team Shop Talk: Help Us Help You
Read Online
August, 2017

Transmission Report: Recognize & Repair Solenoid Accumulators in Late-Model Valve Bodies

Featured in this issue:

  • How to Recognize & Repair Solenoid Accumulators in Late-Model Valve Bodies
  • Essential 4L60/E Upgrades You Can't Miss
  • Transmission Kits Upgraded for Better Coverage
  • 4R/5R Zip Kit® Gets an OE Ratio Upgrade
  • Get CASH for Your Solenoid Cores
Read Online
March, 2017

Transmission Report: Sonnax Voted Tops for Parts & Tools!

Featured in this issue:

  • Sonnax Voted Tops for Parts & Tools!
  • Outsmarting 4L80-E Overdrive Roller Clutch Failure
  • Two Simple Parts Help Guard Against 4L60/E Clutch & Shift Concerns
  • Protect Against 4T60/65-E Comebacks
  • New Performance Parts & Catalogs
Read Online
October, 2016

Transmission Report: Turn Your ZF6 Solenoid Cores into CASH!

Featured in this issue:

  • Turn Your ZF6 Solenoid Cores into CASH!
  • New ZF8 Tech Article
  • ZF8HP45/70 Valve Body Layout
  • Remanufactured Valve Bodies
  • New Toyota and Chrysler Line Pressure Booster Kits
Read Online
July, 2016

Transmission Report: "See" More, Spend Less with Vacuum Testing

Featured in this issue:

  • "See" More, Spend Less with Vacuum Testing
  • Smart-Tech® Performance Upgrades
  • Roadshow Recap
  • Give 'Em the Slip: Avoid Comebacks with Sonnax Slip Yokes
Read Online
March, 2016

Transmission Report: U341E/F TCC Slip Diagnosis

Featured in this issue:

  • U341E/F TCC Slip Diagnosis
  • Ford 6R140 Zip Kit®
  • U341E/F Valve Body Repairs
  • 6L80/90 Performance Upgrades
  • Transmission Digest Top 10 Winners
  • 4L60/E Performance Catalog, Vol. 3
Read Online
October, 2015

Transmission Report: Your Source for Quality Remanufactured Valve Bodies

Read Online
May, 2015

Transmission Report: Learn LIVE with Sonnax!

Read Online
February, 2015

Transmission Report: Sometimes the Best Tools are FREE!

Read Online
October, 2014

Transmission Report: Money in the Bank - The GM/Ford Joint Venture


Read Online
July, 2014

Transmission Report: Hit a Home Run Against 55-50/51SN Problems


Read Online
March, 2014

Transmission Report: Top Repair Solutions for All Rebuild Levels

Read Online
September, 2013

Transmission Report: Always Ask for Genuine Sonnax Parts


Read Online
March, 2013

Transmission Report: Performance Rebuilds & Converters

Read Online
October, 2012

Transmission Report: New Sonnax Improvements for the 4L60 3-4 Clutch


Read Online
March, 2012

Transmission Report: Which Kit is Right for Your Rebuild?


Read Online
October, 2011

Transmission Report: Overheating Honda Converters, Vacuum Testing and More


Read Online
July, 2011

Transmission Report: Hitting the Road with the Sonnax Roadshow


Read Online
February, 2011

Transmission Report: Line Pressure Booster Kits and More


Read Online
October, 2010

Transmission Report: SmartShell® and More

Read Online
May, 2010

Transmission Report: The Art of Proper Bore Reaming

Read Online