• 4L80-E
• 4L85-E

Input shaft failure is a common problem in performance GM 4L80-E and 4L85-E transmissions running with extreme horsepower. OE and aftermarket shafts simply don’t h...Read More

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• 4L80-E
• 4L85-E

Sonnax hydraulic line pressure booster kits contain stronger pressure regulator springs and large ratio boost valves designed to work together to provide progressi...Read More

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• 4L80-E
• 4L85-E
• TH400

Improve GM 4L80-E, 4L85-E and TH400 transmission durability with Sonnax heavy duty intermediate clutch outer sprag race 34663HD-02. It’s an ideal upgrade for perfo...Read More

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• 4L80-E (Dual Stator)
• 4L80-E (Early Single Stator)
• 4L80-E (Late Single Stator)

Sonnax offers the GM 4L80-E thicker cross section, 6-stud lockup front cover GM-CC-11. The strength of this cover is improved by using a one-piece forging with inc...Read More

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’97–’03

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’04-Later

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• 4L80-E
• TH400
• For use with frictions about .080" thick.

Rubber separators can be used in GM TH400 and 4L80-E racing transmission to help keep clutch steels separated and reduce open clutch drag when the clutch is diseng...Read More

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• 4L80-E
• 4L85-E
• TH400

Main shaft failure is a common problem in performance and heavy duty GM TH400, 4L80-E and 4L85-E units. Sonnax heavy duty main shaft 34672-01 is manufactured from ...Read More

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• 10-3/4" NLU
• Buick TH350
• TH400 (3L80), AT-540

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• 4L80-E
• TH400
• .375" Thick

GM ’98-earlier 4L80-E transmissions can suffer intermediate backing plate breakage, clutch failure and case lug blow out when pressures are increased for more clut...Read More

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• 4L80-E
• 4L85-E
• .275" Thick

GM '99-later 4L80-E and 4L85-E transmissions can suffer intermediate backing plate breakage, clutch failure and case lug blow out when pressures are increased for ...Read More

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• 4L80-E
• 4L85-E
• TH400
• TH425

Sonnax extreme duty forward clutch hub kit 34322-02K is manufactured from forged 4140 steel and features nitrited and case-hardened splines to eliminate spline wea...Read More

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• 4L80-E
• 4L85-E
• Fits '95-later units.

Vehicles with GM 4L80-E and 4L85-E transmissions commonly exhibit wear in the #7 Low/Reverse checkball seat location. This issue is caused by normal movement of th...Read More

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• 4L80-E
• 4L85-E
• Short version with late-style design for use with aftermarket shifters.

Ideal for GM 4L80-E and 4L85-E custom transmission builds and performance applications, Sonnax shift lever kit 38512-03K makes it easy to install a short-length ma...Read More

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• 4L80-E (Late Single Stator)

Hardened internal spline

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• 4L80-E
• 4L85-E
• TH400

Main shaft failure is a common problem in extreme duty GM TH400, 4L80-E and 4L85-E units. OE and aftermarket shafts simply don’t hold up in extreme horsepower appl...Read More

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’92–’96, Temperature Sensor in Wire Harness

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• 4L80-E
• 4L85-E
• TH400
• TH425

Sonnax forward clutch hub front washer 34298-078 replaces the OE .063" thick washer in GM TH400, TH425, 4L80-E and 4L85-E transmissions between the forward clutch ...Read More

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• 4L80-E
• 4L85-E

A worn valve or valve body bore can result in incorrect pressures in the transmission, which may lead to poor performance or failure of the transmission. With the ...Read More

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• 4L80-E, 4L85-E, Multi-Plate Performance Converter

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• 245mm LU (3T40, 3L30, TH200C, 4T60-E, 4L60 & E:S-10 only)
• 245mm LU Euro (5L40-E)
• 258mm (Captive Clutch)
• 258mm LU (4L60-E, 5L40-E)
• 280mm LU (4L60-E) “VJCX”
• 298mm LU (TH250C, TH350C, 200-4R, 4L60 & E)
• 300mm (4L60-E)
• 4L60 (700-R4), 4L60-E, 200-4R (298mm NLU) Performance Converter
• 4L60 (700-R4), 4L60-E, 200-4R (298mm) Single Plate Performance Converter (Mounting Ring)
• 4L60-E (298mm), Single-Plate Performance Converter
• 4L60-E (300mm), Single-Plate Performance Converter
• 4L60-E (300mm), Single-Plate Performance Converter (Mounting Ring)
• 6L80 (245mm), Single-Plate Performance Converter
• 6L80, 6L90 (258mm), Multi-Plate Performance Converter
• 6L80, 6L90 (265mm), Multi-Plate Performance Converter
• 6L80, 6L90 (300mm)
• 6L90 (Captive Clutch)
• 6R80, 260mm (Late)
• 6R80, 280mm (Early)
• 6R80, 280mm (Late)
• A465, AS68RC
• A6LF3
• A750E
• A860E
• AB60E/F
• JR403E, RG4R01A
• RE4F04A/V (DA-37,DA-39;DA39)
• RE4R01A
• RE4R03A, 250mm
• RE4R03A, 280mm (DA-30;DA30)
• RE5R05A
• RE7R01A (JR710E)
• RL4F02A (DA-11;DA11)
• RL4F02A (DA-13;DA13)
• RL4F02A (DA-42)
• TF-60SN (VW 09G)
• TR-60SN (VW 09D), Non-Captive Clutch
• TR-80SD (0C8)
• ZF4HP18
• ZF5HP19 (Captive Clutch)
• ZF5HP19 (Single Friction)
• ZF6HP19, 245mm
• ZF6HP19, 245mm (LuK)
• ZF6HP21, 245mm (LuK)
• ZF6HP26, 255mm
• ZF6HP26, 260mm
• ZF9HP48 (948TE)

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