4.0 V6 chain rattle - Percentage

[bogart219]

I noticed my timing chain rattle a few years ago, not certain on mileage. I have 222,000+ miles now, and the chains are loud but no kaboom yet! I change oil every 3,000 miles or less and add STP engine treatment, which I believe has helped postpone the inevitable.

2005 4.0 SOHC Flex

Do you use synthetic oil? If yes is that compatible with STP? Thanks

 

[Sweersa]

Do you use synthetic oil? If yes is that compatible with STP? Thanks

No problem! I use conventional 5w30 Valvoline motor oil. I'm not certain of compatibility of the STP engine treatment and conventional motor oils. I'm assuming the bottle would say whether or not it is. Walmart and most auto stores carry those bottles.

 

[bogart219]

No problem! I use conventional 5w30 Valvoline motor oil. I'm not certain of compatibility of the STP engine treatment and conventional motor oils. I'm assuming the bottle would say whether or not it is. Walmart and most auto stores carry those bottles.

I thought STP was made to be used with conventional motor oil?
You don't think synthetic oil would be better to use?

 

[Sweersa]

I thought STP was made to be used with conventional motor oil?
You don't think synthetic oil would be better to use?

With the number of miles I have, and frequency of oil changes (every 3,000 miles) I don’t think I would benefit from switching to synthetic motor oil.

 

[imp]

With the number of miles I have, and frequency of oil changes (every 3,000 miles) I don’t think I would benefit from switching to synthetic motor oil.

@Sweersa
FWIW, my own experiences with synthetic (Mobil1), were much less good than expected. I tried it in my 65 K car, which had never burned any oil between changes, and in 1000 miles, it was down a quart! Went back to Texaco Havoline, almost none burned, 4000 miles. Never tried Syn. again.

BTW, why Havoline? This was long ago. Everyone was touting Pennsylvania Crude oils: Valvoline, etc. I read Penn. oils were "Paraffinic", Texas oils "Naphthenic" (Havoline). Whatever that really meant, to me paraffin was wax, naphtha was Benzine. Benzine made good motor fuel. Wax, I didn't care for in my engine.

Stupid thinking. Maybe.

 

[bogart219]

Interesting. Thanks! Merry Christmas!

 

[Tech By Trade]

I run synthetic up here, main reason being the temperature swings, When its 30c in the summer it doesn't really do much, but cold starts at -40c it makes a large difference. It flows at cold start much easier than a dino oil at those frigid temps.
Not much for STP, all it does is thicken up your oil, and the goal is to get the oil down those thin little journals that feed the hydraulic tensioners as quickly as possible at startup. Another fellow posted a video of a line run from the pressure sensor to the drivers journal that looks promising the other day. Might actually be worth a try.

 

[Sweersa]

@Sweersa
FWIW, my own experiences with synthetic (Mobil1), were much less good than expected. I tried it in my 65 K car, which had never burned any oil between changes, and in 1000 miles, it was down a quart! Went back to Texaco Havoline, almost none burned, 4000 miles. Never tried Syn. again.

BTW, why Havoline? This was long ago. Everyone was touting Pennsylvania Crude oils: Valvoline, etc. I read Penn. oils were "Paraffinic", Texas oils "Naphthenic" (Havoline). Whatever that really meant, to me paraffin was wax, naphtha was Benzine. Benzine made good motor fuel. Wax, I didn't care for in my engine.

Stupid thinking. Maybe.

My dad and I always used Valvoline for vehicles that called for conventional oil and have never had a bad experience with it so that’s my go-to oil. My dad had a similar issue as you did when switching to synthetic. He uses synthetic in vehicles that always used synthetic, like his ‘97 Viper which is a far different animal from my Explorer! Haha

 

[CDW6212R]

@Sweersa
FWIW, my own experiences with synthetic (Mobil1), were much less good than expected. I tried it in my 65 K car, which had never burned any oil between changes, and in 1000 miles, it was down a quart! Went back to Texaco Havoline, almost none burned, 4000 miles. Never tried Syn. again.

BTW, why Havoline? This was long ago. Everyone was touting Pennsylvania Crude oils: Valvoline, etc. I read Penn. oils were "Paraffinic", Texas oils "Naphthenic" (Havoline). Whatever that really meant, to me paraffin was wax, naphtha was Benzine. Benzine made good motor fuel. Wax, I didn't care for in my engine.

Stupid thinking. Maybe.

I had a similar Mobil 1 experience about 15 years ago. I put it in a previous 91 Mark VII, right before a trip to MN, 1125 miles. It was down a quart when I checked it right after we got there. That car had never used oil before, and with just my mother on the trip, the engine saw easy driving. I bought two quarts and used both by the time we got home. I've never used Mobil 1 since then. I have used synthetic oil though almost all of the time, semi-synthetic in some lesser cars.

 

[CDW6212R]

The SOHC engine has special needs. The main weakness items are the external tensioners, the mechanical springs inside weaken over time. That's where the start up rattle begins. The internal tensioners are not as likely to weaken, but those have plastic surfaces like the cassettes, and are a PITA to change. With quality oil, all of the time, the SOHC will run great, until one or more tensioners allows the chains to run too loose. Then is when you have to provide some care, hear a rattle, change some parts very soon.

My 99 truck with 77,450 miles did not rattle when I bought it. It was wrecked, so while I rebuilt it, I serviced the timing chain parts in front. Now at 152k+, it still doesn't rattle, but with the trans out, I'm doing all of the timing parts this time. I suggest doing something for the SOHC at each 75k mile mark

 

[bogart219]

The SOHC engine has special needs. The main weakness items are the external tensioners, the mechanical springs inside weaken over time. That's where the start up rattle begins. The internal tensioners are not as likely to weaken, but those have plastic surfaces like the cassettes, and are a PITA to change. With quality oil, all of the time, the SOHC will run great, until one or more tensioners allows the chains to run too loose. Then is when you have to provide some care, hear a rattle, change some parts very soon.

My 99 truck with 77,450 miles did not rattle when I bought it. It was wrecked, so while I rebuilt it, I serviced the timing chain parts in front. Now at 152k+, it still doesn't rattle, but with the trans out, I'm doing all of the timing parts this time. I suggest doing something for the SOHC at each 75k mile mark

Thats fine as long as you have the engine or tranny out, have a garage with all the tools, the time, knowledge, help and physical ability to do all that and a extra vehicle to get to your regular job while the one your working on is down.
Im old (62), overweight, no garage, live in cold climate, limited tools, bad eyesight anymore and a short attention span. The golden years
For us regular old shade tree mechanics its too much of an undertaking. All we can do is change the tensioners every 75K and oil at 5K., and hope for the best I guess.
Anymore though after reading this thread I'm not sure what oil is the best to use. Differing opinions. Merry Christmas!

 

[Mgcmgc]

Hello. Just curious. I've been reading about the 4.0 chain rattle, broken guides, replacing tensioners, etc on this board for over a year. I had a slight rattle on start up that went away after a short time. I replaced the tensioners and this seemed to fix the problem. My question is does ALL 4.0 v6's have or is going to have this problem around the 130K to the 170k mile range? What percentage of explorer's with this engine with proper oil changes and maintenance not have this problem?
There are million of these engines out there .Are they all doomed to this failure? Thanks!!

My timing chain went with absolutely no warning sounds!

 

[bogart219]

My timing chain went with absolutely no warning sounds!

That sucks. 14 year old vehicle. What do you do? Fix it yourself if you have the attributes I mentioned above or Pay someone to repair it costing thousands of dollars? Either way your screwed. What did you end up doing?

 

[imp]

That sucks. 14 year old vehicle. What do you do? Fix it yourself if you have the attributes I mentioned above or Pay someone to repair it costing thousands of dollars? Either way your screwed. What did you end up doing?

@bogart219
Having been more involved than most in work involving vehicles over the past 60+ years, I can say that the day when great reliability existed via the Ford and Chevy small block V-8s is gone. However, I remember vividly that the only internal combustion engines back then delivering reliable lives of hundreds of thousands of miles with only routine servicing were the heavy truck diesel engines. The everyday car engines did not. Few times did I witness a 100,000+ mile engine still delivering highly reliable service. Most by then had required major repair work, such as valve reconditioning.

Many of today's modern and far more complicated engines do better than their forbears. Do I agree with the trend of further complexity? Variable Valve Timing, for example?

No, probably not. imp

 

[CDW6212R]

The SOHC 4.0 valvetrain design was not well developed. Good idea, but extremely poor testing for reliability. I guess creating an engine that will survive 75k miles, usually, was the idea.

 

[96eb96]

@bogart219
Having been more involved than most in work involving vehicles over the past 60+ years, I can say that the day when great reliability existed via the Ford and Chevy small block V-8s is gone. However, I remember vividly that the only internal combustion engines back then delivering reliable lives of hundreds of thousands of miles with only routine servicing were the heavy truck diesel engines. The everyday car engines did not. Few times did I witness a 100,000+ mile engine still delivering highly reliable service. Most by then had required major repair work, such as valve reconditioning.

Many of today's modern and far more complicated engines do better than their forbears. Do I agree with the trend of further complexity? Variable Valve Timing, for example?

No, probably not. imp

How do the the Crown Vic SOHC engines see 300K without problems? In some years they used cheap tensioners, and they failed quickly. Those have no VVT, but the 3-valve ones do, and they have tons of issues.

They should have cut down one of those and made a 6.

 

[CDW6212R]

The 4.0 SOHC is an adapted system, to the 4.0 OHV shortblock. The engine wasn't designed to be SOHC from a ground level. The 4.6 engines were all designed to be OHC, so all of the timing chain parts are on the front, and the timing chain system behind the timing cover, is much better than the 4.0 system. I've read of some of the tensioner issues of the modular V8's, that's another Ford thing where they make something without enough long term testing. Thus the first models should be avoided.

 

[imp]

The 4.0 SOHC is an adapted system, to the 4.0 OHV shortblock. The engine wasn't designed to be SOHC from a ground level. The 4.6 engines were all designed to be OHC, so all of the timing chain parts are on the front, and the timing chain system behind the timing cover, is much better than the 4.0 system. I've read of some of the tensioner issues of the modular V8's, that's another Ford thing where they make something without enough long term testing. Thus the first models should be avoided.

@CDW6212R
FWIW, the 4.6 was introduced in 1990, in the Lincoln, guinea pig as usual. Ford's very first automatic transmission offering (a GM Hydramatic purchased from GM), power steering, and power brakes all were introduced in the Lincoln, early '50s or so, exclusive of any of their other cars.
imp

 

[CDW6212R]

Ford seemed to be married to the 4.0 engines, they never made a replacement V6 similar in size, like the modular V8's. It's been so long I forgot wondering when they would make that kind of OHC V6, NA for use in Mustangs etc. When did they make the smaller V6's, the 3.5-3.7's etc? Are those anything like the 4.6's(which are very large externally for the displacement size)?

For the SOHC 4.0, I'm betting the failure rate will make a lot of the Ford postal vehicles available to the public soon. Those based on the 2nd gen Explorers are very good mail trucks, besides not having AC, a radio, or decent window visibility. For the right price, I'd try to rebuild one for myself at work, using the 302/AWD of course. Find me a right hand drive Explorer from England for parts, I could use that dash and AC parts, to "fix" the USPS version.

 

[bogart219]

Just to clarify and to see if I understand correctly, the Fourth generation Explorer's do not have this timing chain issue correct? So they are not using the V6, 4.0 SOHC like previous years? If they are using the same engine what improvements did they make on the engine? Stronger plastic on the cassettes? Thanks!