With almost 400,000 3.5L EcoBoost engines on the road today, these engines have proven to be a solid power unit. Many of these engines are out of warranty and heading to your shop. Here are the top failures and what to look for.

1. REFLASH: There have been at least 7 updates to change calibrations and operation software for the 2011 models to address problems with the vacuum, ignition and transmission shifting. If you notice a loss of power or stalling, check the PCM to make sure it has the latest calibration. TSB 13-8-10 covers 2011-2013 models with the 3.5L V6 and discusses how new software calibrations can resolve a buck/jerk at steady cruise conditions with the transmission in sixth gear and lugging up grades at 1500-2000 RPM.

2. Timing Chain Wear: Since the 3.5L EcoBoost is turbocharged, the oil is under extreme stress. If the driver pushes it past the recommended oil change interval, the first item to show the abuse is usually the timing chain. Worn-out oil can damage the chain, guides and tensioner. When the chain is worn and stretched, the PCM detects the changes in camshaft position and sets code P0016 for crankshaft/camshaft correlation. 

3. Ignition Issues: If you get a 3.5L EcoBoost in your shop with misfire code(s) P0300-0306, pull the plugs and coil boots and look for carbon tracks on the insulator of the plugs. If any tracking is present, replace all the plugs and boots. See TSB 14-0180 for more information.

​4. Induction Cleaning Mistakes: The 3.5L has not had many issues with carbon build-up on the intake valves. But, some DIY owners will use induction cleaners that are injected into the intake. These types of cleaners can damage the turbochargers’ bearings, seals and turbines. The best advice is to use high-quality fuel. Also, Ford has released new PCV parts and PCM calibrations to reduce the amount crankcase vapor ingested into the intake.

The Liberty (2002-2007 KJ and 2008-2012 KK) was Jeep’s replacement for the Cherokee (XJ). The major changes from the Cherokee to the Liberty were an independent front suspension and trailing arm rear suspension. Compared to the Cherokee, the Liberty is actually easier to align.

Instead of having to install offset ball joints and shims to adjust camber and caster, the adjustments are performed with the cam bolts in the lower control arms. The rear is not adjustable.

Front Suspension
The Liberty’s front suspension uses upper and lower control arms. The replacement of the upper control arms can be tedious and require the removal of the battery tray, power distribution center and other components to get at the passenger-side upper control arm.

If serviced, the control arms should be tightened with the vehicle at normal ride height due to the bushings. It is important to have the springs supporting the weight of the vehicle when the fasteners are torqued. If springs are not at their normal ride position, premature bushing wear may occur.

The control arms of the Liberty are robust, but the stock ball joints are recognized as a weak link. Jeep issued five recalls concerning ball joint failure for various 2002-2006 models. Most of the recall documents cite corrosion of the joint as the cause of the failure. The culprit is water intrusion, which has often been blamed on poor sealing of the boot and/or a missing heat shield on early models that allowed the boot to be degraded.
Use care when applying the load to the knuckle so the parts are not damaged, and be careful not to tear the boot. From the front of the vehicle, insert a pry bar to get it rested on the lower control arm and use the lever principle to push the knuckle up until the arm of the dial indicator no longer moves.

Rear Suspension
The rear suspension on the Liberty is non-adjustable, and the only specification is for the thrust angle. When taking the initial readings, pay attention to the thrust angle and suspension setback. If the thrust angle is greater than specifications, inspect the rear suspension for damage or worn bushings.
On 2002-2007 models,  the single upper control link looks like a boomerang and utilizes a single ball joint mounted to the axle. There should be no play in this joint. If it is worn, it may not change the thrust angle, but it will make noise.

On 2008 and up KK models, Jeep changed the rear suspension and ditched the single upper control arm for a four-link setup with a lateral link.

Ride Height
Front ride height is defined by the vertical distance between the spindle and the rear pivot point of the front lower control arm bolt. When the car rolls off the line, the two points should be parallel, +/-10mm.
Rear ride height is defined by the vertical distance between the top of the lower spring seat strike surface and the bottom of the jounce cup (true metal-to-metal jounce travel). This is to be measured vertically inside the coil from the point intersecting the inboard edge and the fore/aft center of the jounce cup down to the strike surface. The distance should be 97mm (+/- 10mm).

For the front and rear, the heights should not differ more than 7mm side-to-side.

Adjustments
Jeep has gone back and forth on whether they should install cams on the lower control arms, but every Liberty has the fences for the cams. Before you quote the price of the alignment, make sure to check for the cams.

Camber and caster angle adjustments involve changing the position of the lower suspension arm cam bolts. Moving the rear position of the cam bolt in or out will change the caster angle significantly and the camber angle only slightly. To maintain the camber angle while adjusting caster, move the rear of the cam bolt in or out, then move the front of the cam bolt slightly in the opposite direction.
 
6 Reasons The Steering Wheel Is Not Straight
1. Rear Toe/Thrust Angle: Rear toe and thrust angle is directly related to the position of the steering wheel while going straight. You can align a vehicle with perfect front toe, but if the rear toe is off, the steering wheel will not be straight going down the road.
2. Tie Rod Length: When performing a toe adjustment, the front tie rods should be adjusted equally so the total toe is within specifications. Adjusting just one tie rod in most cases will give you an off-center steering wheel. 
3. Ride Height: The rear toe is sensitive to ride height on rear independent suspensions. This is done to increase vehicle stability under braking and acceleration. Camber is also a consideration because camber can cause the steering to pull in one direction.
4. Tire Pressure: Inflation is one of the most critical items to check before performing an alignment. A low tire will cause changes in the rolling circumference of the tire. A low tire on one side of the vehicle can cause a pull in towards the side of the low tire and cause the steering wheel to be off-center when driving.
5. Bent Components: Many vehicles have aluminum suspension components. Aluminum does not bend like steel, it tends to break in a catastrophic manner. Most OEMs have engineered components that are allowed to deform in case of a curb impact. Typically, these are toe links, steering arms and control arms. These items might be made of steel so they can bend without breaking.
6. Tire Constructions: Not all tires are the same. Even the same model can have small changes in the manufacturing and construction of the tire. Small changes in layers of the tires can cause the vehicle to pull in one direction. Technicians can solve this problem by changing the position of the tires, or they can use a balancer that can measure the amount of force in a tire and wheel assembly to recommend optimal placement.

In the all-new Ford 5.2-liter V8, the connecting rods attach to the flat-plane crankshaft at aligned 180-degree intervals – creating what looks like a flat line of counterweights when viewed down the axis of the crankshaft. This crankshaft configuration improves cylinder exhaust-pulse separation, improving airflow and increasing power.

When the phrase “bundle of snakes” is uttered about an exhaust system, two cars come to mind: the Ford GT40 and Lotus 38. These were not the first vehicles to use this type of exhaust configuration, but they were the first to be called a “bundle of snakes” and make exhaust systems look more like art than science. These complex exhaust systems were created as a solution to the problem caused by the use of a flat-plane crankshaft.

Most engines use a cross-plane crankshaft. On this type of V8, the crankshaft fires every 90 degrees, and two pistons in a bank are always at the top and firing. This is good for scavenging exhaust gases because the exhaust pulses and the cylinder to be scavenged are on the same bank if using a four-into-one exhaust collector. But, a cross-plane crank does not rev as quickly due to the weight of the rotating mass caused by the counter weights.

A flat-plane crankshaft is lighter due to the lack of counter weights. But, the exhaust pulse needed to help scavenge a cylinder is 180 degrees apart and now on the opposite bank of the engine due to the crankshaft configuration and firing order. This is what the “bundle of snakes” solves.

The bundle of snakes uses two four-into-one collectors. The equal-length exhaust runners crisscross so the appropriate runners are positioned next to each other in the collector to create the scavenging effect.