MARF75

Did any of you use any type of "engine flush" on the initial switch from dino to synthetic??

A friend of mine was told to do this by the Amsoil salesman. I'm a little skeptical, therefore, I would like some input from people I trust.( DTR)
I will be using Amsoil and am pretty sure they make their own product for this, but when I changed the oil in a 4bt, in a Skytrak for said friend I used an "engine flush" off the shelf of the local autoparts. I believe it was Cyclo brand, came in a quart sized container similar to an old cardboard oil can and came out clear.(Im guessing kerosene or similar type product)Directions said dump it in with the old oil and run it for a certain period of time ,which I don't remember.

What's your guys opinion? Any ill effects from NOT using the flush product?
With 114k on the odo, and 5k mile oil change intervals (Rotella 15/40) I can still read the writing on the dipstick through the oil when it's due to b changed. That leads me to believe that it's pretty darn clean in there.
Thanks for your input!

Boatnik

I switched to synthetic and then back again to dinooil. Just couldn't justify the expense. The filter costs plus the oil was to much on my meager income. The polishing filters did not keep up with the soot in my engine and the remote filter installation caused a 20 psi drop in oil pressure at the turbo. I did use the Amsoil flush and it did clean out some gunk without any ill effect. I changed oil yearly and changed filters quarterly. My odomemeter doesn't work. I now run whatever is on sale 15w-40 that is rated for diesel engines and the NAPA Gold filter. I change oil three times a year. My average yearly mileage is about 15,000 miles.

MARF75

What do you mean by " polishing filters"?
I was planning on using the Fleetguard Stratopore filter that is intended for synthetic oil.

peckens

all i can say is when i bought my truck it had had conv. oil at 194k it would get drips of oil out the dipstick tube when I drove on the highway and the oil was always black as hell. Plus with it -24F the truck would barely start unless it was always plugged in. I then switched to synthetic and the dripping stopped. 6 months later i changed the oil with more synthetic. still no leaking and after 3k miles the oil still looks new. truck has 203k btw

I have done the same switch to my previous vehicles: 94 dodge dakota, 2004 silverado, 2003 dodge ctd

I have never herd of flushing the engine. Anywhere.

gyman98

I switched to synthetic and didn't use any type of flush. No Ill effects yet...

93flatbed

Interesting, I had the opposite effect when I ran T6? MY blow by was way worse, stunk like hell and my dip stick had Gonorrhea. I thought it had to do with my over boosted engine. I ended up switching back to dino and its back to where it used to be. No more drips and "normal" blow by and I don't want to vomit with the window down from the stank.

Diesel Dave2

It's weird how every engine is different...I switched to Amsoil synthetic oil at 260K miles(20K since change)...I was expecting some oil leaks...And non occured...Oil pressure,etc stayed the same..

I didn't do any flush on the engine..

j_martin

Back in the "good old days", most dino oil had a high paraffin content, which tended to react with moisture and bacteria, and leave behind quite a bit of gunk. (Modern oils don't have that problem. Had to clean up their act to meet the demands of modern engines.) If you switched to a high detergent synthetic oil, which had no paraffin component, it tended to knock the deposits loose and plug things up, thus the flush recommendation.

Now you can safely disregard that bit of advise, especially if the engine has been reasonably well maintained.

Hvytrkmech

I think your wasting your time with the flush. Change out the oil then do another change at the half service interval then go till your heart is content.

Just to quantify Mr. martins post, all group II oil has paraffin content, it can not be completely removed. The adverse reactions with paraffin sludging or more appropriately with caking was from the byproducts of combustion, not bacteria and only in part from moisture, (an acid concern). Historically this was more an issue for gasoline engines and far less for diesels. The advent of tighter engine tolerances and refined fueling systems mostly eliminated any paraffin based concerns and helped to increased factory recommended service intervals.

Diesel Dave2

Hey "J"...Just a very quick story...Had a 1973 Ford van years back...Decided to use Quaker state high detergent oil...Within 100 miles the motor started to knock...Turned around to head home...Didn't make it...Two connecting rods let loose and twisted in the bores...Even smatched the cam in 3 pieces.....So what you say makes sence..

deanhinsley1963

I like synthetic in gearboxes but not in engines. Every time I've used it in engines it lowers the oil pressure due to lower viscosity and was acompanied by oil consumption.

NJTman

Exactly what I did. I used the seafoam stuff before I switched. Drove around with that in the engine for about 2 weeks, then changed to syn at about 170K. Nothing was noticed when I drained it, other than that greenish tint of the seafoam

Engine starts easier with synthetic. My engine was religiously maintained with rotella 15w-40, so it was already clean. My VC gaskets were bad, so I changed them, but they were also seeping prior to the change. Checked valvelash while i was in there as well.

KRB

I switched with no flush about 75K ago. No problems. Tranny, transfer and rearends all have synthetic in them.

I've switched on two Toyotas too with no troubles. VCs may start leaking but who's to say they wouldn't have anyway?

BC847

I've been known to throw a quart of kerosene into a warm engine and let it idle for ten minutes prior to an oil change. All in the hopes of stripping any varnishes, etc that may have accumulated. Never had any issues doing such.

(I would never do this with an engine that I suspected of having substantial caking of mess for fear of plugging the oil pick-up).

Anyhoot . . . .

I run synthetics in the geared stuff and use to in the engine. I switched back to the regular 15w40 after Zach Hamilton noted substantial wear on his cam stuff with extended oil changes running synthetics due to increased carbon content typical of diesel engines.

KRB

Thats not very encouraging news...