The AW4 is the Aisin-built 4-speed automatic in the Jeep XJ Cherokee, MJ Comanche, and ZJ Grand Cherokee. Built tough but has a few specific failure modes. Here is the guide.
Production years
- 1987-2001 Jeep Cherokee XJ (most years)
- 1987-1992 Jeep Comanche MJ
- 1993-1998 Jeep Grand Cherokee ZJ (some)
- Also used in some Toyota Land Cruisers (similar A340)
Why the AW4 is desirable
- Bulletproof under stock loads
- Tow-friendly 1st gear (2.80 ratio)
- Cheap to rebuild ($800-$1,500)
- Parts widely available
- Better than 32RH alternative
Common AW4 failures
Direct clutch pack:
- Slips in 3rd gear under load
- Most common AW4 failure
- Wear from heavy use / age
TCC clutch:
- Lockup shudder
- P0741 (if OBD2)
- Burnt fluid smell
Pump bushing wear:
- Front leak
- Front pump whine
- Brass particles in pan
Forward clutch pack:
- Slip in 1st-2nd
- Engagement bump from neutral
Throttle valve cable adjustment:
- Misadjusted = harsh or soft shifts
- Cheap fix if not worn out
- Common DIY mistake to skip
Diagnosis
Slip in 3rd gear:
- Direct clutch pack worn
- Rebuild required
No shifts past 2nd:
- Governor pressure low
- Or TCM/wiring issue
Harsh shifts:
- TV cable misadjusted
- Or valve body wear
Burnt fluid:
- Internal clutch wear
- Plan rebuild
Rebuild kit options
Basic rebuild kit:
- All clutches + steels
- All gaskets + seals
- All sealing rings
- $100-$200 kit
Master rebuild kit:
- Includes everything in basic
- Plus filter, bushings
- $180-$320 kit
HD upgrade kit:
- Raybestos HD frictions
- HD pump bushing
- HD direct clutch piston
- $300-$500 kit
What to add for HD use
- HD direct clutch pack (most important)
- HD pump bushing
- Aftermarket valve body shift kit
- External cooler upgrade
- HD torque converter (for Tow)
Install
- Trans must come out
- 3-4 hours just for R&R
- Teardown another 4-8 hours
- Assembly 4-6 hours
- Total: 12-20 hours skilled labor
Cost
DIY full rebuild:
- Master kit: $180-$320
- Torque converter (rebuilt): $150-$300
- HD upgrade parts: $100-$250
- Fluid (Dexron VI, 6 qts): $50-$100
- Total parts: $480-$970
Shop rebuild:
- Parts: $480-$970
- Labor: $700-$1,200
- Total: $1,180-$2,170
Common AW4 misdiagnosis
TCM fault thought to be trans:
- Check ECU connector grounds
- Check TCM power feeds
- Often a $0 fix vs $1,500 rebuild
TV cable mistaken for valve body wear:
- Always adjust TV cable first
- Cheap to test, free to adjust
External cooler thought to be internal leak:
- Check cooler lines first
- Often easy fix
When to rebuild vs swap
Rebuild AW4 if:
- Less than 250k miles total
- No catastrophic damage
- Just clutch wear
Swap to used unit if:
- Cracked case
- Stripped pump bolt holes
- Junkyard AW4: $200-$400
- Less total cost than rebuild
Need AW4 rebuild kit, HD clutches, or torque converter? Shop our AW4 catalog. Master rebuild kits, HD upgrade kits, complete rebuild bundles. Free shipping over $70.
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