I tend to agree with your answer; I just noticed that Seafoam advises it is dual use gas or oil treatment and wondered if anyone had experience with using as an oil additive. In the absence of someone's solid experience I am not too keen on putting it in oil. I will look for the high mileage oil too.

I appreciate your keying me in on the idea that certain additives may cure the seal leak w/o any mechanical intervention....

YHS,
rogerw

 

it was only $12 for 5qt where the Pennzoil for High Mileage was $12.79 for 5 qt.

Normally I would have bought Pennzoil for no good reason other than I have always used it for the past 30yrs, but an auto parts person who said he grew up in his daddy's garage said Castrol keeps the engine cleaner....since it was cheaper too I went with the Castrol this time. I will do the HM oil change today.

Since this is my dad's former truck I don't really know what kind of oil he used in the last oil change anyway.

YHS,
rogerw

 

Sounds like a plan, let us know how it goes.

 

Pawpaw,

I don't know how long it should take for the additives in the High Mileage Castrol 5w30 to have any affect on the weeping seal in my #4cylinder....I have been pulling the plug a few times since the other day and a small amount of oil still appears on the sparkplug.

however, I have replaced the hotter AP104 (only on the #4cyl, all others are AP103s) with a new AP103 and it remains quite clean and white on the inside insulator after about 1 1/2 tanks. one reason would be that the oil change radically changed the amount of dispersant in the oil and therefore it is not coloring the insulator as before.....another may be that it is not weeping as much oil as before, but I am not sure if this is wishful thinking or not. I suppose it should takes weeks and many tanks of gas to know the answer to this one.

However, my last full tank of gas measured 22.3MPG, which beats the previous 21.5MPG and was still mixed town (not heavy city stop and go, but some stop and go) and freeway type driving with airconditioning and "some" heavier acceleration from lights (not all out, but just "respectable"). Sometimes going 55mph, sometimes 65-70mph.

I will soon be going on another 800mile trip to Alabama, and back to TEXAS a week or two later....so I will have ample oppty to report soon again.

As pleased as I am becoming with this B4000, I wish it had a stick instead of automatic, and I wish it had the 4 banger instead of 6. However, it is finally beating my 4.2L 6cyl F150 5-speed straight-shift by greater than 10% and that is good.

Thanks so much for your help!


YHS,
rogerw


PS - I am considering altering the airbox below the stock filter....that seems such a small aperture thru which cold air comes in from the front, and I am thinking it would benefit from getting more air, possibly from the front or possibly from below.....

I am thinking that I have to be careful that I don't degrade its ability to avoid most dust and small pebbles, etc, entering the airbox. Perhaps a larger opening to the front with a fixed screenmesh like screendoor wire? what do you think?

If a clogged filter lowers gas mileage (as it does) is it not possible to get a little more mileage from removing intake restriction? Maybeso.....?

 

I would guess after the 800 mile round trip you should begin to see some difference, IF the High Mileage recipe is going to be able to do anything.

It's extra detegents will likely begin to clean up any engine sludge or varnish deposits by then too, so don't be surprised if the crankcase lube looks kinda nasty by then.

The road trip would be a mighty good time to give it a dose of Chevrons Techron Concentrate Plus, to finish cleaning up the fuel system, intake side & combustion chambers.

The mpg you've posted for the type of driving you've been doing is decent, for the auto 4.0L.

The Rangers cold air intake box isn't restricting it's air flow, so be careful of any mods, so they don't detune your intake.

I'd not use anything but the OEM paper air filter either.

Keep us posted on how things go.

 

All,

As the reader of this thread would know, my last recurring problem is a little bit of oil weeping onto my #4 sparkplug.... I have suspected a leaking valve seal and PawPaw has suggested HighMileage oil as possible fix (it claims to soften and swell old seals). I am running this type oil now.

On the other hand, at this site/page The Ford Ranger 4.0L Engine - The Ranger Station , which is discussing the 4.0L 6cyl OHV engine, I ran across this quote under the heading of "Known Problems" :

Loose Intake Manifold Bolts - Check for loose lower intake manifold bolts. Pull your #5 plug and check it out. If you see the fuzzy head or have some oil present around the sides of the plug then bingo. The 93-94 have this problem VERY often. Usually you can fix it by simply tightening the bolts (in the PROPER sequence), but sometimes you need a new gasket. Do you notice a loss of oil with no leaks? Say 1-quart every 1500-3000 miles?

So, since the symptom matches mine (except for being an adjacent cylinder getting the oil) I have to wonder if this might be my problem/fix. Unfortunately (at least in the shortrun), I loosened the upper manifold plenum in order to get at those lower intake manifold bolts easier, but realized that I needn't have done that so although I broke its seals loose I didn't pull it up and off. The lower intake manifold bolts were not loose but neither were they very tight. The spec is only about 10 ft-lbs, and I tightened them slightly tighter.

I reassembled everything and when I cranked the engine....it would fire up but would not idle....acted like it had a huge airleak. I checked and double-checked and could not find anything not hooked up correctly, but the engine still would not run. So, I dissassemled back enough to make sure I did not let anything get between the upper intake and the fuel rail it seals to....re-assembled and got the same result, engine dies at idle.

Went to bed last night with a heavy heart, what should have been a quick turn of wrenches had turned into another connundrum....the only thing I could think of was that the figure-8 seal rings that seal the upper intake to fuel rail were not sealing anymore. So, went down to Ford this morning and picked up another set of seals. This time I dissassembled all the way to taking the upper intake plenum off, and when I compared the old seals and new ones, sure enough the new ones were thicker in the vertical dimension and the old ones did not protrude out of the groove (ie, compressed with age). Long story short (and it is a long story, getting that intake off was a real pain) when I reassembled this time the idle returned....back to HAPPY again! And in the longrun, I guess I am glad I wound up putting new seals in, since the old ones were so close to not sealing well.

It helped to read Rockledge's thread in the Technical Liibrary https://www.ford-trucks.com/forums/2...ke-gasket.html and know that he also had difficulty with the EGR tube too. In my case I disconnected the EGR vavle itself and also unfastened the oil dipstick tube bracket whose stud also holds the EGR tube to the block. Then, the EGR tube lifted up and out (with some contortion) along with the air intake plenum. Then, removing the tube from the plenum was easy. After seeing how the tube is held in place, I would next time try to pull it off as the intake plenum is raised off its studs and removed, rather than disconnect the lower end of the tube.

So, my lesson I am passing on to anyone else is that just because those seals look like reusable O-ring seals does not mean they can be reused with impunity....for less than 10bucks my advice is to have a new set available anytime you break the seal on that interface....it is not worth the trouble I went to to find this out.

Another thing is my lower intake passages had LOTS of varnish in there. This 98 4.0L has 80K miles on it now and in just the last 3K miles I have run some STP and two cans of Seafoam thru the tank.....should I expect to run more thru before I really clean it up much? Even though I have run most of my vehicles over 200K miles with no problems, I honestly have never used fuel additives until recently under the advice that my engine skipping could be clogged injectors (apparently that was not a problem). I am going to try PawPaw's suggestion of "Chevrons Techron Concentrate Plus" as soon as I locate some.

Hopefully I will see an improvement in my oil weeping #4 cylinder, after having tightened the lower intake bolts. If not, I am a little surer that it is a valve seal, as I have previously thought.

Engine is running great though, and I am a HAPPY MAN!

YHS,
rogerw

 

After thinking about it, I realized that the varnish I found in the lower air intake (as well as in the upper; the EGR tube end had lots of crap on it which I cleaned off) is not affected by my previously adding Seafoam to the fuel, which doesn't enter until the injectors into the cylinders...duh! Most of the wrenching I have ever done before this year was on older carbureted engines....some of my mental mistakes are due to "carbureted" thinking....

So, can I put some Seafoam into the regular upper air intake? Is this worth doing? Or is it dangerous to have that crud let loose all at the same time? Is it better left alone?

Any informed opinions?


YHS,
rogerw

 

Don't ingest the Seafoam through the upper intake until just before you want to change the crankcase lube & maybe the plugs, as it'll likely really dirty up the oil & maybe the plugs too.

 

As mentioned above my last problem in this newly acquired B4000 was/is a slight oil weeping in #4 cylinder probably either due to leaking valve seal or the intake manifold gasket. At PawPaw's suggestion I began using High Mileage oil (5w30 Castrol). I also re-torqued the intake manifold bolts.

Here is a pic of the #4 spark plug after about 3000 miles, including a 2000mile roundtrip of highway miles during the past 2 weeks:




You can see oil on the lower threads (symptomatic of either gasket or seal leak) and discoloration on the inside insulator. It is more red-ish than the dark tan of the previous plug....however there is much less of the discoloration than before. All the other sparkplugs remain very clean.

The engine ran GREAT during the entire trip. Best mileage was 22.5mpg at 62mph on cruisecontrol and 21.3mpg at 72mph on cruise (two different tanks of gas on return trip), both with AC running. Thanks so much to PawPaw and to this Forum for help and guidance.



YHS,
rogerw