UK Engine Guide
Three engines were available in the UK ZJ range. Each tab below covers specification, known issues, and UK survivor figures in the same format.
Specification
| Type | AMC 4.0-litre inline-six OHV, cast iron block and head |
| Power | 174 to 190bhp (varies by year) |
| Torque | 225 lb-ft at 4,000rpm |
| Gearbox | 42RE 4-speed automatic |
| Transfer case | NP242 Selec-Trac (standard on all 4.0-litre UK ZJs) |
| Economy | 18 to 22mpg real-world |
| Towing | 2,500kg braked |
Known Issues
- Cylinder head cracking. Caused exclusively by overheating. If the temperature gauge moves past normal and the car keeps running, the head will crack. The repair cost typically exceeds the value of most examples.
- Rear crankshaft seal seep. Near-universal above 100,000 miles. Gearbox-out job at £250 to £450. Many owners monitor oil level and accept it.
- Exhaust manifold cracking. Cold tick that fades when warm. Common. Aftermarket replacement manifolds available.
- Crankshaft position sensor. Fails when hot, stopping the engine. Cranks normally but will not start for 20 to 30 minutes until cool. Under £30 to fix. Carry a spare.
- Timing chain and guides. Cold rattle on startup is the warning. Replace before it skips a tooth.
UK Survivors (DVLA Q4 2025)
| Variant | Licensed | SORN |
|---|---|---|
| Laredo A (petrol) | 16 | 77 |
| Orvis A | 66 | 290 |
| Limited (ZJ era est.) | 151 | 892 |
Limited figure is an estimate based on manufacture year filtering. See How Many Left page for methodology.
Recommended choice for most buyers. Strong parts support from RockAuto and US specialists, well-documented failure modes, and genuine longevity when maintained properly.
4.0-litre engine bay, 1998 Orvis. "4.0 Liter" rocker cover correct for this model year.
First service on purchase: Thermostat, all coolant hoses, water pump, ATF+4 transmission fluid, transfer case fluid, and 75W-90 GL-5 in both differentials. Do this regardless of claimed service history.
Specification
| Type | VM Motori 2.5 turbodiesel, inline-four, Italy |
| Power | 115bhp |
| Torque | 221 lb-ft at 2,200rpm |
| Gearbox | 5-speed manual (the only UK ZJ with a manual gearbox) |
| Transfer case | Part-time system |
| Economy | 27 to 35mpg real-world |
| UK sales period | February 1997 to end of production |
Known Issues
- Injector wear. Have injectors tested before purchase. Reconditioned sets available from UK diesel injection specialists but allow lead time.
- Injection pump. Specialist reconditioned units only. This is the primary parts challenge with this engine.
- General neglect sensitivity. Less forgiving of poor maintenance history than the American petrols. Budget for remedial work from day one.
UK Survivors (DVLA Q4 2025)
| Variant | Licensed | SORN |
|---|---|---|
| Laredo TD | 11 | 133 |
| Limited TD | 3 | 13 |
| Total diesel ZJ | 14 | 146 |
Figures from manufacture year filtering to 1999 and earlier.
Expert purchase only. 14 taxed diesel ZJs on UK roads. Parts sourcing requires effort, fewer garages have experience with the VM engine, and when work is needed most owners struggle to find someone willing to do it. The reward is genuine economy and genuine rarity.
Specification
| Type | 5,211cc V8 OHV, Chrysler LA family |
| Power | 208 to 212bhp (ECE) |
| Torque | ~290 lb-ft |
| Gearbox | 44RE 4-speed automatic |
| Transfer case | NP249 Quadra-Trac (permanent AWD) on V8 models |
| Economy | 14 to 18mpg real-world |
| UK RHD status | Unconfirmed. Verify build sheet before buying. |
Known Issues
- 44RE transmission damage from incorrect ATF. Only Mopar ATF+4 or MS-9602 specification. Many UK-registered V8s have had wrong fluid historically. This is the leading cause of transmission problems on these cars.
- Crankshaft position sensor. Same hot-stall failure mode as the 4.0-litre. Carry a spare, under £30.
- Running costs. At current UK fuel prices, 15mpg is an expensive daily commitment. Budget honestly before buying.
UK Survivors
No reliable ZJ V8 survivor count is available. There is no ZJ-specific V8 DVLA entry. V8 ZJs appear across multiple generic Grand Cherokee categories alongside later generation cars and LHD imports. No clean separation is possible from DVLA data.
RHD status unconfirmed. Per Honest John Classics, the 5.2 V8 was initially sold LHD only in the UK. Verify the build sheet before buying any UK V8 ZJ. See the Models page for full detail.
Transfer Cases
| NP242 Selec-Trac | Standard on all 4.0-litre UK ZJs. Offers 2H, full-time 4H, part-time 4H and 4L. Selectable up to 55mph. The most practical system for UK use. |
| NP249 Quadra-Trac | Fitted to V8 models and some 4.0-litre cars with the optional AWD transfer case. Permanent full-time AWD with a viscous coupling centre differential. No driver selection required or possible. All four tyres must be the same size at all times — mismatched sizes accelerate centre differential wear significantly. |
Axles
| Front: Dana 30 | All UK ZJs. 3.55:1 ratio. Watch for pinion and carrier bearing wear on high-mileage examples. A whine at motorway speed is the first sign. |
| Rear: Dana 35C | Non-tow 4.0-litre models. Bearings run on the half-shaft. Wear scores the journal, so shaft and bearing usually need replacing together. |
| Rear: Dana 44 | Tow-pack and V8 models. More robust. Sought as a Dana 35 upgrade donor. |
Fluid Specification
- Front and rear differentials: 75W-90 GL-5. Change on purchase regardless of claimed history.
- Automatic transmission: Mopar ATF+4 only. Chrysler MS-9602 specification. No substitutes.
- Transfer case (NP242): Mopar NP242 fluid or equivalent per FSM specification.
- Transfer case (NP249): ATF+4 also used in this unit. Verify against FSM for your model year.
UK Survivors
Drivetrain-specific survivor data is not available from DVLA entries. See the How Many Left page for full variant figures.
Running-in after differential work: After any differential rebuild, use 75W-90 GL-5 and allow 500 to 1,000 miles before checking for leaks or unusual noise. Change the fluid again at this point to remove any metal particles from the running-in period.