Originally Posted By: 01rangerxl
I did it on my 2001 2.5 Ranger at 75K miles. 1/3 through the brake booster vacuum line, 1/3 in the oil, and 1/3 in the gas. It made a cool smoke show, but that was about it. I changed the oil 500 miles later. A lot of people replace the spark plugs, but I didn't. The truck really ran exactly the same after.
Be prepared for it to foul your spark plugs though. It can happen. Also, take your time getting it into the engine, and don't use more than 1/3 of a can! People have hydrolocked their engines with stuff like Seafoam. Also, if you put any in the oil, change it soon.
If your engine runs good, there may be no benefit to Seafoam. I have no plans to Seafoam my current truck. It runs exactly like it should. On a car with a lot of carbon buildup, it might be a good idea though. If I bought another div>
You can use the whole can through the intake and it won't hurt a thing if done correctly. I've done it countless times on many vehicles. The Mopar stuff is great stuff if you can get your hands on it.
I usually run a can through the intake once a year. Then put a can or two of Chemtool in the gas tank. Run the tank empty, then run another half tank through it. Then change the oil, filter, fuel filter, and pull the plugs to check them out and regap if needed.