The Dodge 4.7L is a decent entry-level engine for workhorse trucks that featured in several prominent lines throughout the middle of the 2000s. Dodge engines are known for being powerful with decent, if not top tier, reliability. This 8-cylinder Dodge engine falls within those expectations.
Pushing the engine above 150,000 miles is not uncommon amongst owners, and many go well above 200,000 miles. Along the way, the engine will need a careful eye and consistent maintenance to reach that mileage. You may experience issues with the coolant system, head gasket, valve covers, and valve seats.
An engine with decent performance requiring highly reliable maintenance from its owner is no surprise. The engine is prone to oil waste buildup inside the engine, leading to performance problems and overheating. Give it a fresh dose of SAE 5W-30 at least every 3,000 miles – sooner if you’re putting it through its paces.
Many of the issues will stem from overheating, especially if you put a lot of strain on the engine. That means any problems with the coolant system can quickly cascade into further issues. Stop operating the engine immediately if you notice it overheating. Regularly check your coolant levels for any signs of a leak. There may be a tiny hole or loose connection in a hose, or the radiator cap may not be operating properly.
If you spot a leak or notice frequent coolant loss, take steps to identify and fix the issue as quickly as possible. Coolant repairs are generally cheaper and less impactful when handled proactively than the more serious issues that come from an engine that is consistently running hot. The exact parts needed to fix the issue will vary with the vehicle model and source of the problem.
Blown Head Gaskets
The head gasket can develop leaks and eventually blow, and the tendency for the 4.7L to lose its gaskets is a sore spot on its reputation. Keeping the engine cool and well-oiled will reduce the likelihood, but it can happen even with tender, loving care. Once the gasket blows, it’s best to call a tow truck and have it replaced immediately.
Because of the location of the head gasket, replacing it is beyond the means of most amateur mechanics. Expect to pay much more for the labor than for the part itself. The HS26157PT1 or HGS1101 head gasket set paired with HBK1101 or ES71129 head gasket bolts are readily available and fairly inexpensive. It’ll still be worth the repair cost, though take it as an indication to be extra diligent about the maintenance.
Damaged Valve Covers
The valve cover is constantly heating and cooling throughout the life of the vehicle. The expanding and contracting warp the shape of the cover and can lead to further damage. In a worst-case scenario, the valve cover will develop severe cracks and break.
The 264-928 and 264-929 valve cover replacements are decently expensive despite being plastic components, but they shouldn’t break often without another underlying issue. Make sure to select the correct side if only one is damaged. Replacing them at home is a possibility for those who know their way around an engine, but take it to a mechanic if you are at all uncertain.
Valve Seat Damage Or Dropping
The valve seats are the contact points for the exhaust and intake valves. Damage to the seats can develop over time, leading to some performance and efficiency loss in the engine.
In a worst-case scenario, the valve seat will drop entirely. This can be due to previous damage, a sudden deformation, or a defect in the seat. The valve can drop into the cylinder and cause significant damage if you continue to run the vehicle.
Valve seats don’t have to be checked too often, but they should be inspected with other long-term maintenance tasks to limit the risk of dropping. Replacing the valve seat itself is not a major job, but the damage from a dropped seat can quickly rack up the repair bill.