Symptoms
None. It's a service item, and owners schedule it around 75,000–100,000 miles. A truck with no record is due.
The fix, step by step
- Drain the coolant and remove the fan and shroud, the accessory belts and the crank pulley, then the timing covers.
- Set the engine to top dead center and confirm the timing marks on all the cam pulleys and the crank before removing the old belt.
- Replace the belt, tensioner, idlers and water pump, plus the cam and crank seals if they're leaking.
- Turn the engine twice by hand and recheck the marks before reassembly.
- Refill and bleed the cooling system.
- A BITOG owner adds: use a genuine Isuzu thermostat.
Tools & part numbers
- Crank-pulley holder
- socket set
- torque wrench
- coolant
- factory service manual.
Where to buy the parts
Timing belt and component kit, 1998 Trooper 3.5RockAuto ↗Amazon ↗
Water pumpRockAuto ↗Amazon ↗
Timing idlerRockAuto ↗Amazon ↗
ThermostatRockAuto ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Isuzu Trooper (second generation) parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.