My truck started having the oil pressure light flicker when idling. I had my local shop put in a high-volume oil pump, new pick-up and screen, and replace the rear main seal while they had the pan off. They said they cleaned out a good amount of gunk from the oil pan. They also told me my bearings looked "pristine".

So now I've got good oil pressure; problem solved as far as I'm concerned. But I was wondering... if there was gunk in the oil pan, would there still be gunk in the oil passages of the engine? Should I have the engine flushed or leave it be?

Truck is a 1996 Ram 1500 4x4 5.2/auto with 204,000 miles (4.10 gears, true-tracks front/rear) 285/75/16" tires with 2" lift front/rear.

 

Personally, I would steer clear of adding any harsh or straight solvents in the engine oil, including those made for engine flushes. Those solvents don't lubricate all too well and they won't withstand the pressures motor oil can, so you're relying on them incorporating with your oil uniformly when you've added them.

If it were me, I would take a milder approach and simply shorten your oil change intervals for a while, taking advantage of the fresh oil's detergent package to do some of the cleaning. I'm thinking like 1000-1500 mile changes for a while.

I stock up when I can find oil for $2/qt for a known brand or trusted supplier. And filters are just over $3. So, at about $13 it doesn't really break the bank either.

 

Gotta go with JSTMoto above, and my 45 years of old man tinkering. No additives, or flushes. Change your oil more frequently for awhile as JSTMoto suggests. The problems with flushes are legendary, often involve new, post flush oil leaks through softened/damaged seals.
To check further, and put your mind at ease, pull a valve cover, and have a look inside the cover, and at the valve train itself. If it's gunky up top...clean what you can, and keep the OCI short.
Gunky/dirty deposits, possibly from neglected oil changes of a previous owner, collect in oil passages and can get "bake-on".
It stands to reason that any chemical strong enough to remove carbon buildup, might also be strong enough to damage other components that come in contact with the oil flow, especially in newer engines with all the composite materials.
No manufacturer, that I'm aware of, lists engine flushing as a maintenance procedure in the owner's manual!

 

This ^^. Good advise.

 

I use engine oil flush products on my daily driver, high mileage vehicles (200,000 miles plus). Never had any issue with them, nor have I ever lost an engine to failure in all of my 40+ years of driving. Typically, I use a product like Gunk engine flush, which you add to the oil, let the engine run 5-10 minutes and then immediately change the oil and filter. I usually perform this procedure at every other oil change. Works fine for me.

 

Maybe I'll just do some frequent oil changes for a bit then. That seems to be the consensus.

 

Synthetic oil will clean it out faster than regular oil. Truck oil will do the same. Use Rotella T6 truck oil for the fastest cleanout outside of potions like ATF (good) diesel (not so good). A little at a time is the best way to go. If you don't choose syn then regular Delo or Rotella would be great.

http://www.bobistheoilguy.com/forums...s.php?ubb=cfrm is a great oil 'site. Fantastic place for having everything you thought you knew about oil to be wrong.

 

Here's what Click and Clack, the Tappet Brothers have to say on their Car Talk website about Engine Flushing !

Funny Guys!

http://www.cartalk.com/content/i-hav...hing-other-day