Replaced the rear timing chain tensioner today

[06EBMG]

Started getting a very light rattle on start-up and every now and again after a hot soak re-start from the rear timing chain. Installed the new rear tensioner after I got off of work. When I compressed the old one it had very little resistance and oil came squirting out of the tensioner side. This was done right after I had shut the engine off after driving home from work, which is a 30 minute drive for me. So it had plenty of oil in it. I did not prime the new tensioner the old school way. Instead, I removed the fuel pump relay (#49 in the power distribution block) and cranked the engine until the oil pressure light went out. I let the starter cool for 30 seconds and checked the tensioner for leaks, then cranked again for another 10 seconds. Fired it up after re-installing the relay and was greeted by sweet silence. Checked the tensioner periodically for leaks while I let it idle for 15 minutes. Took it out for a good 45 minute drive after a quiet idle, so far so good. I know how these timing chains CAN go, so I was pleased as punch when the old one was actually shot. Glad it did not go the other way. (Knocks on wood)
Definitely worth doing every 75k miles. With the part being so reasonable to purchase, I think I will do mine every 30k miles as preventative maintenance.
A note to 4th gen owners who have not done this yet: In my case, I had to remove the entire fender liner assembly to get a straight shot at the tensioner. After removing the small flap, there was no way to get a good purchase on the tensioner. The fender liner takes all of 5 minutes to remove, and it makes the job cake once done. Also allows the torque wrench to remain perpendicular to the tensioner for a good positive "click".
Keep the bottom side down everyone.

 

[michael loibl]

Thanks for the encouragement, I’ve been thinking about changing the tensioners on my own 2006 with a 4.0 Liter. 145,000 miles and so far no noises But it has lived his whole life on Motorcraft semi synthetic oil and filters

 

[06EBMG]

Mine was owned by a Ford tech since 2011. He bought it when it was traded in by an older couple at the dealership he works at. They had purchased it from the dealer new and maintained it there religiously. According to him, they get a new vehicle every 5 years and have owned Explorers since 1996. Motorcraft oil filters and semi-syn oil since new. Mine has 184K on the clock and the internals still look like new.
The rear tensioner is no biggie at all. You will have no problem with it as long as you have a 27mm 6 point shallow-ish socket. You will also need about 16-18" of extensions and possibly a breaker bar or a 1/2" drive with a cheater pipe on it. Thread it on by hand. You should be able to thread it nearly all the way to the head. If you want to prime the tensioner before you install it then soak it in some oil and work the tensioner assembly back and forth until it gets very hard to push, nearly impossible. I just removed the fuel pump relay and cranked the engine until the oil pressure light went out, then another 10 seconds of cranking just for good measure. I did it in my driveway with my floor jack, jack stand and basic tools. Took me all of 45 minutes start to finish.
I am going to replace the front one just for good measure tonight. Ford finally re-designed the intake and when they did the front tensioner now comes out with very little effort, so might as well get it done. I went with Cloyes. Make sure the box says "Made in Italy" on it. Cloyes sources parts from all over and sometimes they will use tensioners made in Taiwan or wherever. You DO NOT want those. The ones that are made in Italy are the same ones you buy from the Ford dealer. Purchased mine from a local O'Reilly's so I could make sure the parts came from Italy. Of course, you can always go to the Ford dealer and get them there.

 

[Explorer_PL]

This is a post I've been waiting for. I am hearing some rattles in our 4.0 and wanted to do the simple, easy stuff before pulling the engine out. Just was not sure if the tentioners can be replaced without any special tools or steps like locking the chains or something.

Definitely in the schedule for this summer.

Thanks 06EMBG

 

[swshawaii]

OP, did your original rear hydraulic tensioner have a sealing gasket? Mine did not and leaked after tightening to 50 ft/lbs. Loosened and tried 60 and it still seeped. Crossing fingers went to 70 until it sealed. Can't imagine the PITA it would be if I stripped the aluminum threads.

Oil stains ABOVE the tensioner port were from a previously leaking valve cover gasket.

 

[swshawaii]

This 1/2" drive 20 inch extension was a life saver.

Sears.com

 

[06EBMG]

@swshawaii-The original did have the sealing ring. My new one came with one too. However, the new one had a "wave" pattern to the ring, which is why folks have to use some grease to hold it centered on the new tensioner. I decided to re-use the original sealing ring because it was already "formed" to the tensioner base which meant I did not have to wipe grease on the new tensioner to get it to stay centered. If you re-use the original sealing ring just be sure to push it all the way to the base of the new tensioner. If it is fully seated you will see no "gap" between the ring and the tensioner. As long as you do not do something belligerent it will stay centered without any fuss. Thread it in by hand, you should be able to get it nearly seated to the head. I set my torque wrench to 50lb-ft (spec is 49 when re-using the original sealing ring) and let her eat. No leaks.
I went ahead and installed my new front tensioner today while I had a break at work. Instead of removing the sensor on the thermostat housing I just grabbed a 1 1/16th wrench and removed it. All I had to move out of the way to do it was the connector for the sensor. I also re-used the original sealing ring on the front too. Since it is so easy to get to I just tightened it down by feel. Primed the new tensioner using the crank-no start procedure outlined above and started her up. No issues. While the engine was running I tightened up the tensioner until no more seepage was present. Worked great.
Good luck. Keep the bottom side down.

 

[MotorCityFats13]

I thought everything to do with the chains had to be done at once and engine removal was mandatory

 

[donalds]

Here is some info
Ford 4.0L SOHC Timing Set Replacement - YouTube

 

[Littleant]

Thank you for your post. Informative.

 

[Argentimage]

Here is some info
Ford 4.0L SOHC Timing Set Replacement - YouTube

This is a Ranger Engine pull...

The big question is, from earlier posts, can this be done, front and rear, in the vehicle?

Does anyone know of a video of how this sounds?

I'm hearing it more hot than cold...

 

[Fix4Dirt]

This is a Ranger Engine pull...

The big question is, from earlier posts, can this be done, front and rear, in the vehicle?

Does anyone know of a video of how this sounds?

I'm hearing it more hot than cold...

it can ve done in the vehicle, the hydraulic tensioners aint hard. indont have a sound sample thoigh. they are noiseiest when cold and when theres insuficient oil pressure, so i wonder if thats really your issue

 

[Argentimage]

it can ve done in the vehicle, the hydraulic tensioners aint hard. indont have a sound sample thoigh. they are noiseiest when cold and when theres insuficient oil pressure, so i wonder if thats really your issue

I made a video

Sounds worse the iPhone picks up fan and exhaust as well

Maybe I can put on YouTube and copy the link

 

[Fix4Dirt]

I made a video

Sounds worse the iPhone picks up fan and exhaust as well

Maybe I can put on YouTube and copy the link

yes, please post a video. an image is worth a thousand words. vudeo is worth millions of words

 

[Argentimage]

yes, please post a video. an image is worth a thousand words. vudeo is worth millions of words

 

[Argentimage]

This is from the inside at start up very short

 

[Argentimage]

This is from the inside at start up very short

Here is another from the fender well, again to get away from fan noise.

 

[Fix4Dirt]

huh i see. whereabouts is it coming from if you can tell? that doesnt sound like hydraulic tensioner (imo)

 

[Argentimage]

Here is another from the fender well, again to get away from fan noise.

I'll also say that I have used synthetic 5w30 since 20k miles, changed at 3-4000 mile increments.
Now at 200k miles.
Very early 2005 production unit.

 

[Fix4Dirt]

I'll also say that I have used synthetic 5w30 since 20k miles, changed at 3-4000 mile increments.
Now at 200k miles.
Very early 2005 production unit.

good- syn >conventional, and short oil runs are great for these motors imo, keeps em runnin much much longer. youre doin the right hign imo! just not sure if it sounds like tensioner to me. my timing rattle didnt sound like that, ti was a metallic tinging... and constant from startup all th way to shutdown