When Was the Timing Chain Rattle in the SOHC 4.0 Fixed?

[cbxer55]

I have a 07 Mustang with the 4.0. I am not sure what model 4.0 it is though. It has 120,000+ miles and no rattle at all. I have no clue what oil the other owners use, but I am using Mobil One 10W-30 in it now. Also drive a 4.0 Ranger at work, not sure what year, but it is also very quiet.

My 3.0 Ranger with modified exhaust (no muffler, dual outlets in front of the tire) and cold air supplied cai with a JET chip on the computer, pulled a 2000+ pound trailer from CA to OK when I moved here in 02. It did excellent. Kept it in OD, except when pulling uphill. Ran 70, 76 and even 80 with that trailer behind it.

For those critical of the "bra", it's no longer there. I took it off recently, cleaned up the front end sufficiently that I threw the "bra" in the round-open-top file. I did keep the mesh part that covers the grill opening. It has attachments top and bottom, so I cut it off the main bra and tossed the rest. I like how clean my ac condenser is with no dead bugs or bird bodies in it. I am looking for a billet grill so I can delete the mesh as well. Found a billet grill at CARiD. It fits in the openings as an overlay, so the center parts don't have to be cut out, like some of the grills do.

 

[Arolsma]

This is why I think the 4.0 OHV was the pinnacle of the Cologne's design lifetime. Other than pushrod rattle (mine does it a bit when cold ), they seem pretty stout. Sure, the HP isn't sky high, but the torque isn't much different, and at least my 1995 does very well for itself. Much better than the 3.0 1995 I had before... good motor, just didn't belong in a truck. Even a street truck.

I kind of wish they had made it for a few more years; but as it is, the newest ones are nearly 21 years old . I am guessing I will get better reliability out of an 05 sohc than an 2000 ohv since all the rubber components and such will be failing on a 21 year old truck. Also, most all trucks that old are rusted to bits around here.

 

[franklin2]

I kind of wish they had made it for a few more years; but as it is, the newest ones are nearly 21 years old . I am guessing I will get better reliability out of an 05 sohc than an 2000 ohv since all the rubber components and such will be failing on a 21 year old truck. Also, most all trucks that old are rusted to bits around here.

In my experience, anything 10 years or older is going to start requiring more serious parts replacement. Like balljoints and other steering components. U-joints, axle bearings, etc. The breakdowns seem to come in waves.

 

[cbxer55]

In my experience, anything 10 years or older is going to start requiring more serious parts replacement. Like balljoints and other steering components. U-joints, axle bearings, etc. The breakdowns seem to come in waves.

Me and a friend did the entire front end on my 98 Ranger in July 2018. Not a terrible job to do, took about five hours. Had the truck on a lift Tuesday to change the trans fluid and filter, second time in 20 years. Checked everything over while in the air, cleaned everything. My u-joints are still perfectly fine at 22 years old. I just wish they put zerk fittings on them. Stock front end had none, the new one does. I have one leaking axle bearing, going to take it to the same place that did the transmission, a friends shop. He said he could do them easily. I am going to buy an aftermarket diff. cover before hand, likely TA.

 

[Arolsma]

https://www.underhoodservice.com/exploring-service-needs-on-the-ford-4-0l-v6-engine/
This article says that the GUIDES were improved in 2003, but a higher mileage 03+ 4.0 sohc can also develop the problem. (What do they consider higher mileage? Nobody knows. )
https://www.ranger-forums.com/4-0l-ohv-sohc-v6-tech-33/03-4-0-sohc-rattle-help-159980/
This guy says the TENSIONERS were replaced with a new model tensioner in 2004.
So were the guides improved in 03 and the tensioners in 04?
It sounds like I won't have problems IF I get an 03+ that doesn't currently make the noise and appears to have been maintained well, right? I am now having second thoughts on getting any 4.0 sohc since I can't really find any hard evidence regarding when/if this problem was fixed. A 2.3 with an automatic might be my best bet. If anyone could post a link to some authoritative source regarding when problems with the timing chain were solved, it would be greatly appreciated. Thanks for your responses so far.

 

[rubydist]

Your plan of a 03+ is a good one, and if its been maintained decent it will be fine - which applies to any 10+ year old vehicle.

btw, getting a 2.3 w/ auto is fine if you are okay with measuring 0-60 times in minutes rather than seconds...

 

[MikeG]

If it's running decent, just replace all that stuff (tensioner and guides) and then you don't have to worry about it. Right?

 

[RonD]

1997 was first year the 4.0l SOHC was used in Explorers
The timing chain issue is/was NOT a 100% failure rate, MOST 1997 - 2003 4.0l SOHC never had the issue

But there was about a 15-20% failure rate which was way way too high for any engine or transmission for that matter, lol
"The rattle" was originally blamed on owners who didn't service the engine(change the oil) when required
But Ford Dealers started to see the same issue on the 4.0l SOHC's they had been servicing since new, so blaming the owner was out the window, lol

Ford engine designers got on the case, turns out the 2 long chain tensioner's internal springs were failing
The springs hold the long chains tight during start up, until oil pressure can take over
So while cranking the chains could bang on the guides, and a guide would eventually break, and THAT'S THE RATTLE, broke guide, so chain can't be held tight against it

I don't think there was any redesign of the guides or chains, but there was a redesigned of the tensioners
The new tensioners were available in late 2001 early 2002, but...............the 4.0l SOHC, like most engines, is assembled at a separate plant than where the vehicles are assembled
So the engines assembled in 2001 go into 2002 vehicles, and engines assembled in 2002 go into 2003 vehicles, ect....
So 2003 Ranger 4.0l "should be OK"
2004 for sure
But any tensioner can fail, thats just the nature of mechanical devices.
Because these long chain tensioners are not that hard to replace, and the down side of one failing is pretty far down, i.e. PULL THE ENGINE to repair, why not just replace the 2 tensioners every 100k miles or when you buy a vehicle with the 4.0l SOHC
It's a great engine, good power to weight ratio and as trouble free as engines can be otherwise

 

[RonD]

Just saw this video at another forum

Its about the front drivers side tensioner on the 4.0l SOHC and an oil pressure issue because of clogged passage over time
Very good simple solution IMO

 

[gw33gp]

When I did my timing chain cassette and tensioner replacements, my brother warned me about this problem. I took the plug out and checked for anything that shouldn't be there. It was very clean and I put it back together. I never had a timing chain rattle so there was no indication that there should have been a problem with oil restriction in that area..

 

[DILLARD000]

When I did my timing chain cassette and tensioner replacements, my brother warned me about this problem. I took the plug out and checked for anything that shouldn't be there. It was very clean and I put it back together. I never had a timing chain rattle so there was no indication that there should have been a problem with oil restriction in that area..

Same here when I recently replaced my left+right tensioners. Removed the TorxHead pipe plug, then flow restrictor with tweezers.
A little carb cleaner sprayed in the holes, re-inserted restrictor, re-sealed pipe plug with a lite smear of RTV.
Oil & filter change after tensioners were done.

http://vignette.wikia.nocookie.net/2001fordexplorersporttrac/images/6/62/2001.Ford.ExST_Engi.Tmng_Left.Redx_Ford.yL2z-9e473-aa.GIF

"donalds" just made a video of a right tensioner that he cutaway length wise; some interesting items found inside.
There's a BallCheckValve & Rubber\PlasticSeal that seem much more suspect than the spring going bad.

Ford Timing Chain Tensioner Cutaway

Thought I'd post this. Thought it'd help someone. Any thoughts?

www.explorerforum.com

 

[franklin2]

Your plan of a 03+ is a good one, and if its been maintained decent it will be fine - which applies to any 10+ year old vehicle.

btw, getting a 2.3 w/ auto is fine if you are okay with measuring 0-60 times in minutes rather than seconds...

There are a lot of boring cars and trucks out there that never need any expensive repairs. I will admit it's hard driving them everyday, but if you can afford it, you need at least one boring car in the fleet as a back-up.

 

[RonD]

I have a 1997 Toyota Camry 4cyl auto, father-in-law bought it new, lost his license(thank God) when he turned 80, we bought it from him, our kids drove it as each got a license and until they could get their own cars
Still have it
It will not die
Son try to kill it once when he ran it without coolant, had to replace head gasket, and also did timing belt at that time
Our out of town friends drive it when they visit
And I use it to run and get parts if working on my Ranger

I have to say, whatever Toyota did on this car they did it right, brakes, tires, battery and coolant are all I have ever done(except the head gasket, lol)

 

[Arolsma]

I don't think there was any redesign of the guides or chains, but there was a redesigned of the tensioners
The new tensioners were available in late 2001 early 2002, but...............the 4.0l SOHC, like most engines, is assembled at a separate plant than where the vehicles are assembled
So the engines assembled in 2001 go into 2002 vehicles, and engines assembled in 2002 go into 2003 vehicles, ect....
So 2003 Ranger 4.0l "should be OK"
2004 for sure
But any tensioner can fail, thats just the nature of mechanical devices.
Because these long chain tensioners are not that hard to replace, and the down side of one failing is pretty far down, i.e. PULL THE ENGINE to repair, why not just replace the 2 tensioners every 100k miles or when you buy a vehicle with the 4.0l SOHC
It's a great engine, good power to weight ratio and as trouble free as engines can be otherwise

Thank you so much for your reply! This is the info I have been looking all over for.

Is replacing the tensioners something a nube to working on cars (ie, me) could do? I have heard the tensioners are something like $80, and you need to change the coolant at the same time you replace the tensioners. Anybody know roughly how much it costs to have a small independent shop do this job?
One thing I don't understand is why so many people say this problem wasn't fixed until 2005.

 

[sgtsandman]

It depends on how mechanically inclined you are and what you have in the way of tools. The job isn't hard but it is a bit time intensive since you have to remove the accessory belt idler pulley and the thermostat housing in order to remove the driver's side (left) tensioner. Draining some coolant out of the engine through the radiator drain will need to to be done. The intake hose and throttle body needs to be removed as well. Expect it to take you about 6 hours if you take your time and you only have hand tools.

The sockets you need are 7mm, 8mm, 15 or 16 mm for the idler pulley bolt, 27 mm or 1 1/8" deep well, and a 27mm or 1 1/8" box end wrench. To remove the hose clamps, you will need a 5/16" for the intake and long reach, angled needle nose pliers for the coolant by pass, water pump, and upper radiator hose. I found water pump pliers jaws to be too fat for some of the hoses and ended up using the needle nose pliers for the re-installation. It is easiest to disconnect and connect the water temp sensor after you have loosened the thermostat housing and before re-installing the water pump housing. You will also need to remove the accessory belt. A belt tesioner tool makes this much easier.

The steps to do the work:

1. remove the intake hose
2. disconnect the throttle cable and throttle position sensor connector
3. remove the throttle body
4. drain about a gallon of coolant out of the radiator
5. remove the accessory belt
6. remove the tensioner pulley
7. remove the thermostat housing cover and disconnect the sensor connector
8. remove the thermostat
9. remove the lower thermostat housing

That is about as much room as you are going to get to work on the driver's side chain tensioner short of removing the intake manifold. With a deep well socket and a wobble extension, you will be able to remove and install the new one. Reassembly is the reverse. Expect to have to refill the coolant over flow reservoir a couple of times after the engine has cooled down and the system sucks in coolant to replace any burped air after driving and getting up to full temperature.

The passenger side (right) is much easier. Remove the tire. Pull back the rubber splash shield. Remove the tensioner and install the new one. Re-install the splash shield and tire.

Expect leaks. This is where the 27mm or 1 1/8" box end wrench comes in. If the driver's side tensioner is leaking, you will need to tweak it a little at a time until the leaking stops with the box end wrench. Use brake cleaner to clean the oil residue after each time you tweak it to make sure the leaking has stopped. No leaking is acceptable, not even a light staining. What looks like a little bit is more than that and will flood the valley between the heads under the intake and empty your engine of oil. Again, the passenger side is much easier to get at if there is any leaking there.

What a shop would charge, I haven't any idea. Figure $100 per hour for the labor plus parts and taxes. Since they will have air tools, they will be able to get it done faster but I wouldn't hazard a guess as to how much faster that would be. If the above work I laid out for you seems too much, it would be well worth the money spent paying a shop to do it right instead of paying them later to fix what you did wrong.