A lot of sludge in the motor 3.9 I seen engine flush on the shelf of walmart I'm wondering if it's worth the money to buy this stuff? Do it work? Is there anything better or just leave it alone

 

The best way to remove it is to remove it by hand. The problem with the chemicals, if they work, is that the sludge comes out and can clog oil returns, the pickup, passages, etc.

How bad is the sludge?

Do some short oil changes with a good regular motor oil - Pennzoil Yellow Bottle for example.

 

I use a quart of Rislone right before doing an oil change on engines that have sludge. Rislone is basically like Diesel fuel. I've also heard of folks using a quart of transmission fluid (highly detergent).

You do NOT want to rev the engine to high while it's in there. Only let it run/idle for around 10 minutes or so. It will lower the viscosity of your oil and CAN wipe (spin) a bearing if you get careless.

Dan is correct when he says sludge CAN clog oil pump pickups and passage ways. Be aware of that.

And yes, change out the oil frequently 500 miles or so after you run the Rislone. Earlier the better for the next few oil changes.

Way back when dinosaurs roamed the earth, I had a 72 Pontiac LeMans with a 1970 400ci in it out of a big old Catalina. Bought the Catalina cheap, pulled the engine, pulled the valve covers and holy shiiitt was it SLUDGED up! I cleaned out the valve train and galley (under the intake), rinsed the snot out of it with diesel fuel. I then threw in a Ram Air III cam, slapped on some headers and a Holley 650 (and other goodies). Ran like a **** it did! Not many cars around could beat it! LOL !! Oh! Those were the days! LOL!

 

Look to be a lot. I just looked in the oil cap. I don't think I need to take things apart. The motor runs good and it's only a 3.9 v6 so I don't expect to do 200 foot burnout with the sludge gone but do need to do the valve cover gaskets so I gess I'll just see how much in in there before I start pouring (mr clean)lol into the pan. I was just wanted to know about the products out the and if is a good idea to use them. I herd that sea foam works good. I might just do the synthetic oil quick changes to see what happens

 

If you have heavy sludge use the newer cleaning oils it will slowly dissolve the sludge and not dislodge the chunks only problem is you should change the oil more often now for 2 or more years.

 

Oh, but you can XD

When I changed rockers, I had zero sludge in the top end. I also now run conventional. 10-40 instead of 10-30. One is because i have methanol-assist-on-demand, two is that with age, tolerances open up and the slightly thicker oil can help close them back up artificially and bring oil pressure back up. I also have my stickers shorted to 2500 miles instead of 3000. Now that I drive 100 miles a day, I may shorten it further to 2250 or even 2000. Depends how much racing I do this year.

If you want sludge, you're welcome to see the dragster's oilpan after a handful of races. It comes OFF every 10 race weekends to shovel all the sludge out.

 

I use a good full synthetic oil. Those don't sludge up.

 

I've long used Gunk's Motor Flush right before an oil change - you pour it in, idle the motor 5 to 10 minutes, then drain and change oil and filter both.

Now, if you look in the oil filler, you see metal - some black, some shiny, but you DON'T see sludge.

Every seal on the motor wants to leak now, though - however, it IS a V6 with 290,000 approx. miles on it, so ...

RwP

 

I used Seafoam years ago after i saw the oil i drained shortly after getting my truck. Next oil change did the seafoam treatment, 1/2 bottle in the oil, half into the gas. Drove it to work about 4 miles and back and noticed oil pressure was low. Changed out the oil/filter and found some crud/gunk. Did another oil change about 1000 miles again and found the oil looking clean and the pressure up more than ever.