2004 4.0L timing chains | Ford Explorer Forums - Serious Explorations

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2004 4.0L timing chains


Active Member
September 19, 2014
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City, State
Martinsville, Indiana
Year, Model & Trim Level
2004 ford explorer XLT
A few weeks ago my timing chains failed on my 04' explorer XLT 4.0L. Wanted to get your guys' input on how I should proceed... Below is a picture of the failed tensioner


With the crankshaft lined up and timed with #1 piston at TDC it appears the drivers side camshaft is currently about 25 camshaft degrees out of time. When I turned the crank to put #1 @ TDC I did not feel nor did I hear any sort of interference. However, I'm not sure if I even would. The chain seems to have a pretty good amount of slack on both sides.

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primary chain slipping

I don't recall any member ever reporting that the primary chain had slipped on their SOHC V6. When I had my engine apart I unsuccessfully tried to slip the chain with no tensioner installed. However, it is possible for the jackshaft sprocket to slip on the jackshaft. If the primary chain or the jackshaft sprocket had slipped both camshafts would be out of time.

How did you determine that the driver side camshaft was "25 camshaft degrees out of time." This is what it should look like when piston 1 is at TDC on the compression stroke.

The timing slot should be below the axis of the camshaft and parallel to the head surface that mates with the valve cover.

Well, with the #1 piston at TDC the drivers side camshaft is about 1/4 turn out of time according to those pictures above. However, I suppose something else could have slipped I'm just not sure what did I assumed the chain since it has a considerable amount of slack in it.

check the cassette

Are both camshafts out of time or just the driver side?
The passenger side should look like this.

If only the driver side is out of time then I suggest that you check the cassette guide on that side. It may be broken.

Edit: The photo you posted doesn't show the balance shaft chain tensioner. Is it also broken?

I'm going to head outside here about an hour as soon as it warms up a little bit and I'll remove the passenger side valve cover. The balance shaft chain appears to still be in good shape. The guide/tensioner that broke on the primary chain looks to be in good shape thickness wise, not sure why it snapped in half though. I do suspect the guide on the driver's side head is broken, as it was rattling quite loud prior to slipping time.

Today I pulled off the pass. side valve cover and immediately noticed the camshaft was also out of time..


I than decided to turn the crankshaft just a tad and figured out the passenger side camshaft does not move at all with the crankshaft, and driver's side camshaft.

Your rear jackshaft bolt probably snapped, I see that a lot once a truck is ran with bad chain guides. I see a good amount of sludge also. In this situation it will cost you at least $700 in parts to correctly fix the engine with quality parts then you have the labor. I suggest finding a lower mile used engine from a 06+ which had the most revised timing setup on it and swapping the long block in. You can use one from a mustang, explorer or ranger up to 2010.

sorry about the bad news!

I encourage members to inspect the passenger side cassette first. That way no time or money is wasted on in vehicle engine repair when eventually the engine would have to be removed. Unless you just want challenge and learning experience by repairing the engine yourself I agree with boominXplorer's advice. In addition to the cost of timing chain components, head gaskets, and probably valves there is the cost of the special tools needed. Also, the SOHC V6 is not a simple engine to time and can easily be mistimed resulting in more damage and aggravation. However, I've heard that low mileage engines are getting harder to find and their cost is increasing. If you purchase one with more than 75K miles you could experience the same failures in the not too distant future.

Yea, that makes sense. At least it explains the *pop* I heard right before the engine died. I have not decided what I want to do yet. The oem ford chains in this motor lasted 171k miles which isn't bad and it's quite a bit more miles than I've ever put on a motor. I would be rebuilding the motor myself, I've done several motors over the years. Another route is to find another low mileage motor and put my new chains in it, before putting in my truck. Alas, I'm not in a rush to decide what to do as it's not my daily driver.

Here are some reasonable engines that you could just "swap in"

Ford Ranger 35K!!!, CLEAN, RUNS GOOD, 35K!!! 35,000mi A 00142082 $950 Liberty Auto Salvage, Inc. - PRP Midwest USA-IN(Evansville) Request_Quote 800-444-9373 / 812-423-6271

Ford Ranger 78K!!!, CLEAN, RUNS GOOD, 78K!!! 78,344mi A 00141598 $850 Liberty Auto Salvage, Inc. - PRP Midwest USA-IN(Evansville) Request_Quote 800-444-9373 / 812-423-6271

Ford Ranger 4.0,8-11,RWD,RUNS WELL 5,444mi A A85805 $1350 Jones Auto, Inc. USA-IN(Orleans) Request_Quote 812-865-4161

What are some things I should watch out for when looking for a new motor? I know some members have various issues with different year motor swaps. Since mine is 4x4 as well as flex fuel should I be looking for a motor that came from a 4x4 vehicle with the flex option? Does it matter if it comes out of an automatic or manual? I know my 2005 audi a4 the manual and automatic models come equipped with different crankshafts than one another. If I remember correctly the 4x4 motor has an extra balance shaft. There are boat loads of salvage years here in the Indianapolis area. I've found quite a few 4.0s here locally from all different types of cars and years.

I've been pricing parts to do a rebuild on my current 4.0L motor and I'm over the price of a nice used low mileage engine. I'm liking the idea of the 06+ 4.0L, their actually cheaper than the older 4.0L motors, and they also have less miles. I had my eyes on a 2010 ford ranger 4.0L motor w/54k miles, and it appears to be nearly identical aside from the intake manifold. I'm unsure if it is 4x4 or whether it came from a standard/auto vehicle.