AW4 Rebuild Basics

Difficulty 5/520–50 hrs$500–28001987-1990, 1991-1995, 1996, 1997-2001

Short answer

Overhaul kit ~$200-400. Most DIYers send the OD section out and do the main case at home. Watch for solenoid and 3-4 clutch wear.

Underside view of a driveshaft and U-joint running into a rear differential between two mufflers — Photo: Wesley Tingey on Unsplash

The AW4 rebuild is doable in a home shop but not trivial. The standard advice: pay a trans shop to do the overdrive section (requires specialty spring compressor) and do the main case yourself.

Rebuild kit contents (e.g., ExtremeTerrain 53007998KT, Transtec):

Friction discs (3-4 clutch pack, forward, direct, OD)
Steel plates
Gaskets and seals (front pump seal, rear output seal, valve body separator plate gasket)
Bushings (front pump, planetary)
Bands (intermediate, OD)
Filter and pan gasket

What usually needs replacing at high mileage:

Front pump bushing (groove visible)
3-4 clutch pack (charred friction material)
Solenoid pack inside valve body (electrical drift)
TCC lockup clutch in converter (a new converter is cheaper than rebuilding the OEM)

Tooling: standard mechanics hand tools, a snap-ring tool set, a press for the OD section (or send it out), a flat clean workbench. The shop manual or the Toyota A340 manual (they're 95% the same internals) is mandatory.

Timeline: a competent DIYer takes a long weekend. A pro shop turns the job in 2-3 days for $1500-2500 all in.

Cost reference:

Reman trans (Jasper, Monster): $1800-2800 + core + shipping
DIY with kit and new converter: $500-700 in parts, plus your labor
Junkyard pull AW4 from a 97-01 XJ: $300-600, totally a gamble

Why it works

save money vs reman
learn the trans

Trade-offs

specialty tools
OD section gotchas
straightforward to leak

Tools required

snap ring tool set
torque wrench
press (or trans shop access)
flat workbench

Parts

Part	Vendor	Est. price
AW4 rebuild kit	Transtec/ExtremeTerrain	~$380
AW4 torque converter (reman)	Sonnax/Punch	~$180

Sources

Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.