Grand Cherokee
Overview
Known as the WH in Australia (WK in North America), this third-generation Grand Cherokee was sold here as Laredo, Limited and the V8 Overland, plus the off-road-focused 5.7 SRT-adjacent grades. It moved to a fully independent front and rear suspension (a first for the Grand Cherokee) which sharpened the on-road manners at the cost of some extreme-articulation ability versus a live-axle rival. Four engines reached Australia: the 3.7L PowerTech V6 petrol (base), the 4.7L PowerTech V8 petrol, the 5.7L HEMI V8 petrol and the much-loved-but-fragile 3.0L CRD turbo-diesel V6 (the Mercedes OM642). The diesel and the petrol V8s drive through Mercedes' five-speed W5A580/NAG1 auto; the 4.7 used Chrysler's 545RFE. The big draw is enormous value and a genuine dual-range, full-time 4WD system (Quadra-Trac II / Quadra-Drive II) for very little money. The catch is patchy reliability and a thin, expensive dealer/parts network in Australia - the OM642 diesel in particular suffers oil-cooler 'black death' leaks, swirl-flap and EGR problems, while the HEMI/4.7 are thirsty and have their own exhaust-manifold and lifter foibles. Buy on documented service history, not on price alone. Classed here as a warn-tier 4WD: capable and cheap, but the running costs and out-of-warranty repair bills catch out unprepared buyers.
Engines & variants
3.0L CRD turbo-diesel V6 (OM642)
Pros
- Strong 510Nm makes it the best tourer/tow engine of the range
- Smooth, refined Mercedes-sourced V6 with good economy for the size
- Far better real-world range than the thirsty petrol V8s
- Genuine dual-range full-time 4WD for very little money
- Mercedes W5A580 auto is robust when fluid is serviced
Cons
- OM642 oil-cooler 'black death' seal leaks are near-universal at age/km
- Swirl-flap and EGR carbon problems can destroy the engine if a flap ingests
- Expensive, labour-intensive repairs and a thin AU diesel-specialist network
- Turbo VGT vanes stick from soot; throttle/limp-mode faults common
- Diesel deleted mid-2008, so good examples are scarce and aging
Known problems
5.7L HEMI V8 petrol (EZB)
Pros
- Effortless V8 performance and a great tow engine
- Strong, characterful HEMI soundtrack
- Quadra-Drive II with e-diffs is genuinely capable off-road
- Chain-driven - no belt service
- Cheap to buy because petrol thirst scares buyers off
Cons
- Very thirsty, especially around town and towing
- MDS cylinder deactivation linked to lifter/cam tick at higher km
- Exhaust-manifold bolts shear and manifolds tick on a cold start
- Mercedes NAG1 auto needs fluid services or it gets harsh
- Expensive AU running costs offset the cheap purchase price
Known problems
4.7L PowerTech V8 petrol
Pros
- Smooth, no MDS deactivation complexity of the HEMI
- Cheaper to buy than the HEMI or diesel
- Chain-driven, no belt service
- Chrysler 545RFE auto is reasonably tough when serviced
Cons
- Underwhelming torque versus the HEMI and diesel for towing
- Still thirsty for the modest performance
- Exhaust-manifold gasket leaks common
- Less desirable, so weaker resale than HEMI or CRD
Known problems
3.7L PowerTech V6 petrol
Pros
- Cheapest way into a Grand Cherokee
- Simpler than the V8s, no MDS
- Chain-driven, no belt service
Cons
- Underpowered for a heavy 4WD - sluggish loaded or towing
- Still drinks fuel for the modest output
- Base Quadra-Trac I lacks a true low range on some cars
- Least desirable engine - lowest resale
Known problems