I have some friends who swear by using internal engine cleaners b4 changing thier oil and some who say it is a no no, what do you think. I have a 93 Ranger with a 3.slo that has 170k on it and I have only run Mobil1 in it and recently a qt. of Lucas oil stabilizer at oil changes.I currently have a knock when the engine is cold and not when it warms up. Ive been told cleaner will take care of that, i dont believe it, need expert help. Thanx.

 

If it has a knock, no cleaner will help it. Is it a knock or is it a stuck lifter you are hearing?

I have almost 300K on mine, I just checked the oil on the dipstick, almost 4000 miles since last change still clear so if yours is clear and not all black and tar like, I doubt you need a cleaner. Cleaners will/may cause other problems if they break sludge ans stuff loose than can cause blocked channels etc. If you want to clean you will need to pull the pan and see whats at the bottom then make a decision from there.

 

This is good advise, unless you like dropping the oil pan to clean the oil pump screen, stay away from engine flushes. All that gunk has to go somewhere!

 

If it is a stuck lifter would it knock all the time or quit once the engine is warmed up? When I change my oil at 5000 miles the oil is still usually in good shape. I like your quote at the bottom of your info old93junk, that is 2 kool.

 

If you've had the vehicle since new & have always run Mobil-1 in it with 5K OCI's, it's likely clean inside.

Depending on the kind of noise, it kinda sounds like it may be CCDI, or as Hank sggested, maybe a varnished up lifter.

CCDI= Combustion Chamber Deposit Interference. It's caused by carbon deposit build up on the piston crowns & head, such that the piston makes contact with the head through the deposits in the "squish zone".

This kind of knock sounds like marbles clacking together & Ford calles it "marble noise & it usually goes away after the engine warms a little & things expand enough to give clearance in the squish zone, only to return after the engine cools off.

My 4.0L has had this this problem since new & Ford even developed a TSB "decarbon proceedure" for it, which is listed in the "Tech Info" thread atop the forum.

I've found a decrbon method that works for my 4.0L, thats less time consuming & costly, as it doesn't require a plug, oil & filter change afterward.

Just run out most of the current tank of gas & at the pump, Before gasing up, add Chevrons "Techron Concentrate Plus" at the on container specified oz/gal ratio,

I do it with a tank of Chevron, Texaco, or Cal Tex gas as they alrady have some Techron in them, so with the Techron Concentrate Plus, we get a treat rate thats 10X the pump gas alone.

Then employ the high rpm part of the decarbon TSB daily, during use of the tank of treated gas & use up most of the treated tank before refilling.

If CCDI is the problem, you should notice a difference by the end of the first tank of treated gas. If it's better but not completely gone, dose another tank & repeat. I usually get results in one tank that'll last at least six months, sometimes a year.
Autozone has had a two-for-one deal on the 12oz Techron.

If the noise is more of a "tic" like Hank mentioned & you think it's a deposit related problem & are insistant on pouring something into the crankcase, maybe consider Auto-Rx for engines, as spesified.

Which is a rather expensive combination of three Ester's, that naturally have good detergent & dispersant properties, that can slooooowly soften, dissolve & put into suspension, gum, varnish, sludge & ring land carbon deposits, so the filter can grab them, all without messing with or fighting our oils chemistry.
Auto-Rx Engine Cleaner

They do suggest using it with a mineral based oil, not a synthetic like the Mobil-1 your using.

It takes longer to get results, but would probably be safer than any solvent based "engine flush" product.

Some oil filters are known to cause start up noise. Motorcraft don't, so if your using other than the specified Motorcraft oil filter, maybe consider changing & see what happens.

Using a higher than specified viscosity oil in cold weather can also cause start up noise.
The Lucas will make your oil thicker than it would normally be, so I wouldn't use it with your Mobil-1 in cold weather, it doesn't need that kind of help anyway!!!!

A bunch of engine noise thoughts for pondering. Let us know how it goes.

 

I've heard you should run sea foam through a 3.0 when it gets high mileage as there bad to carbon up.

 

Should I put it in the oil b4 an oil change for a few miles or in the fuel? How long should I run it?

 

Read the instructions on the can, I would say it would go into the oil. I never used it myself as I never owned a 3.0 out of the 7 rangers that I've owned. I read an article that sugest using sea foam in a high mileage 3.0 as they are bad for carbon build up.

 

I tried the seafoam once. You have to suck it in thru a vacumm line for carbon buildup, then let set for a while. Makes lots of smoke so neighbors may not like you.

Didnt really see any benefit, but it would hurt in all liklihood. Put the good cleaner in the tank for carbon, seafoam, techron, even ATF from what I have read. run for a while to ensure its mixed into the fuel. then try to run the tank out at one time if possible, varying the rpms from normal to high, basically run the thing WFO for a mile or so if it will to see if it will clean it selft. The old cars used to build up carbon from the crude oils in use, the lead in the fuel etc so everyone would take the vehicle out to "blow the carbon out" in the highway. City driving is terrible, and yes you do need to once in a while take it out to "blow it out". I have almost 300K on my 94, runs the highway everyday, knock on wood no problems.