Transmission Parts

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450-43LE

Cutback Valve Kit 94987-01K

Fits '98-later models: Isuzu NPR, GMC Forward Tiltmaster, Chevrolet Forward, Nissan UD and Mitsubishi Fuso Trucks.

Helps cure:

Engine stall on engagement
TCC apply concerns
Broken sleeve
Low line pressure
Low boost pressure

450-43LE

Boost Valve Kit 94987-09K

This kit fits '98-later models: Isuzu NPR, GMC Forward Tiltmaster, Chevrolet Forward, Nissan UD and Mitsubishi Fuso trucks.

Helps cure:

Delayed Reverse
Flare shifts
Clutch distress
Low line rise

5R55N • 5R55S • 5R55W • U151E • U151F • U250E

Tool Kit F-27741-TL13

42RE • 42RH • 46RE • 46RH • 47RE • 47RH • 48RE • A727 • A904

Oversized Lockup Boost Valve Kit 22771-19K

'94-Later with boost oil delivery tube

Helps cure:

TCC slip under load
No line rise during TCC apply in 4th
Overheated converter
Loss of lube oil
High line pressure with no indication of boost
No lockup
TCC cycling

6L45 • 6L50 • 6L80 • 6L90

Oversized Converter Feed Limit Valve 104520-11

Helps cure:

High TCC slip RPM
Code P0218
Code P0741
Overheated converter
Inadequate lubrication
Excess converter pressure

42RE • 42RH • 44RE • 44RH • 46RE • 46RH • 47RE • 47RH • 48RE

Neutral Safety Back-up Insulator Service Kit 22229-07K

Fits ’02-Later with 5-terminal switch

Helps cure:

Lost or damaged component

C6 • E4OD

Rear Case Bushing 36008B

Fits '89-'94 units. Early-style with 3 grooves to front, no grooves to back.

Bushing Style: Precision
Material: Steel-backed bimetal
Width: 1.620"
Shaft Dia.: 1.470"
Housing Bore: 1.593"

Helps cure:

Premature wear & bushing failure
Inadequate lubrication

722.6

TCC Damper Valve Kit 68942-23K

In late-style units only. Early-style units do not have TCC damper valve.

Helps cure:

Harsh lockup

6R100 • 6R60 • 6R75 • 6R80 (2009–2014) • 6R80 (2015-Later) • ZF6HP19 • ZF6HP26 • ZF6HP32

O-Ringed Internal End Plug Kit 95740-25K

Fits ZF6HP19/26/32 (Gen. 1) units without 053 separator plate code.

Helps cure:

Inconsistent shift quality

4F50N • AX4N

Bypass Clutch Control Plunger Valve Kit 96206-03K

.486" OE large spool diameter

Helps cure:

Code 628
TCC cycling
TCC surge
No lockup
Lube failures
Excess cooler circuit oil loss

EZ-Lap Diamond Hone EZ-LAP-HONE

4L30-E • AR25 • AR35

Boost Valve Kit 54200-01K

Medium ratio, OE code 448

Helps cure:

Low line pressure
Burnt clutches
Soft upshifts
Delayed Reverse

F4A-EL • F4EAT • GF4A-EL

Boost Valve Kit 74846-01K

No TV cable, electronic transmissions, factory-style sleeve, no O-rings

Helps cure:

Low line rise
Low line rise in Reverse & shudder
1-2 Quality poor
Delayed Reverse

A4CF1, A4CF2

Boost Valve Kit 84741-01K

Helps cure:

Soft shifts
High line pressure in Reverse
Low line rise in Drive

6F50 • 6F55 • 6L45 • 6L50 • 6L80 • 6L90 • 6T70 (Gen. 1) • 6T75 (Gen. 1)

Tool Kit F-104740-TL12

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