ATP Automotive AT-205 Re-Seal Stops Leaks, 8 Ounce Bottle

I have to say that it is very rare I would ever use or recommend anything from the "snake oil" section of an auto parts storeThis AT-205 I had researched and felt as comfortable as one can be using any additive.I had purchased a 2006 Ford Explorer with a very minor leak at the rear main seal. I am sure starting with a very minor leak helped to.The vehicle literally looked brand new. It looked like the leather seats had never been used. There was not a single mark on the paint. The motor and transmission worked flawlessly. The only thing I intended to do is replace the plugs with high end Iridiums, the old ones were worn but nothing about their condition otherwise.Its a big job to replace the rear main seal so I decided to give this a try along with a high end oil and filter change then another after a short time to help remove some of the sludge.I added a bottle of this with the second oil change and obviously the seal swelled as intended and there was no more leak.I had a motor that had been well maintained and a very minor leak. Had the leak been worse I suspect this would not have worked as well, fix things fast before they get worse and more expensive.But I was fortunate and this additive was a legitimate product and did what it was designed to do.There is no question this worked in my case and saved me big money if I had needed to replace that sealIf your leak is minor then I have to recommend giving this a try. It is one of the rare items that actually worked as intended.I am very happy with the results.I have watched how spraying this on rubber suspension parts extends their life as they do dry out. Not a bad idea and perhaps save some big amounts of cash.

I got a 2001 Chevy truck 4x4 with the 4.3 Vortec. It leaks a little bit of oil. If you know, dropping the oil pan on a 4x4 gm is not the easiest job to do, so I decided to try at205 and see if it can do anything about the oil leak.The timing cover, the oil pan gasket, and the rear main seal is all seeping a little bit of oil. The whole oil pan is wet, but it’s not a big enough leak to ever drop on my driveway.I poured 2/3 of this bottle into my engine, because my engine takes 4.5 quarts of oil.I will drive the truck with at205 in the engine until I see an improvement, and I will post an update below.I bought three bottles of at205, because I will also use this product on all rubber parts on my truck, like the weatherstripping and bushings.Will update if I see an improvement with the oil leak.Edit:UPDATE at 3 days since I poured it in the engine:I went under my vehicle and washed off all the oil and dirt buildup two days ago after I poured in the at205 and did a quick 30 minute drive, on day 1.I went under the vehicle again today (day 3), and there still is a very little bit of oil coming out of the front main seal, but I do not see any oil from the rear main seal or the engine oil pan gasket. It is dry. The front main seal leaking is now very very minimal. Not even enough to coat the underside of the oil pan anymore. Super happy to see this.I will post an update again in a couple days. I will wash the underside of the engine again tomorrow, then post an update on day 6.

Almost seems too good to be true, but it's actually 100% as advertised. Had a pretty leaky rear main seal and oil pan gasket on an older VW. Put this in, drove around 150 miles and the leak has more or less completely stopped.Given the cost of a rear man seal replacement, you'd be crazy not to try this first. $20 sure beats several thousand.Highly, highly recommended! One of the best automotive products I've ever used.

Scotty Kilmer said AT-205 is watery and harmless because it’s a polymer. I’d never heard of a watery polymer. ATP calls it a plasticizer. A plasticizer is a solvent used to make a polymer more rubbery by loosening the bonds between molecules. This one seems to be diethylene glycol monoethyl ether.ATP says it won’t harm internal components. The website says it’s compatible with conventional and synthetic oils, ATF, gear oil, power steering fluids, and hydraulic oil. It has a 3-minute video, which for 5 seconds presents a chart of recommended amounts with three columns of seven figures each. Do they really expect you to digest that in 5 seconds?For those 5 seconds there are two lines of print below the chart. If you pause the video, they are grayed out and covered with ads. I had to replay that segment several times to be sure I understood. They say, “Recommended use is approximate due to blending properties with oil. No risk if slightly over treated.”Contrary to their assurances, this implies a risk. It seems as if ATP did not intend for the viewer to see the warning.The video devoted a minute to showing the representative open a hood, pour in a bottle of AT-205, and close the hood. An Amazon customer reported that after he did so, the concentrated solvent in the oil pan caused the paint to come loose and clog the screen on his oil pump. It’s not a new product, but the video didn’t recommend running the engine to mix the solvent. Buyer beware!My 35-year-old car occasionally smoked on startup. Probably the valve seals were worn or shrunken. Deposits from oil additives damaged spark plugs and O2 sensors. AT-205 would be a lot cheaper than having the seals replaced, but I was afraid AT-205 could expand seals more than necessary, and that could accelerate wear.For 4 quarts, ATP recommends 6oz, or 180ml. The oil would have about 4.7% solvent. I decided to try 100ml (about 2.7%) and add the rest if necessary. I used a polypropylene measuring cylinder. It measures precisely, pours as neatly as using a funnel, and rinses better than glass. I ran a short errand to mix it and ran another short errand the next day. Then I cleaned the grime below the valve cover gasket, which leaked.Months have passed. The gasket has not leaked, and I haven’t seen or smelled any oil smoke.My riding mower was 25 years old. An unseen oil leak caused chaff to accumulate on the cooling fins, hidden under the housing. That interfered with the flow of cooling air. It often smoked on startup. I didn't know if leaky rubber seals caused either problem.I added 25ml of AT-205, about 1% of the oil in the crankcase. I mowed a few minutes to mix it. The next day, I cleaned off the oil and grime. in the months since then, the engine has stayed clean, and it hasn't smoked on startup.The next time I have a leaky machine, I’ll start with 0.5% to minimize risk. I can always add more.Update: Scotty was right about using AT-205 to preserve plastic parts. My positive battery terminal protector uses a "living plastic" hinge. It had stiffened so that it wouldn't stay down. A couple of applications of AT-205 improved it. My big concern was the duct from the MAF meter to the throttle. It had become brittle over the years. It looked impossible to fabricate a new one with all those hose fittings. I've applied AT-205 three times. A little goes a long way. I put a teaspoon or so in a cup and apply it with a cotton ball. I also wipe it on pneumatic hoses. Plastic absorbs it slowly, so I check after a couple of days. Skin absorbs it readily, but research has shown it's harmless (pharmacologically inert).Another update: The manufacturer of my mower engine recommends oil changes according to engine hours and doesn't mention time intervals. I waited two years. During that time, the oil continued to feel and smell okay.Two weeks after the oil change, I got a lot of oil smoke on startup. I had assumed that the solvent not immediately absorbed by the rubber had evaporated from the old oil long ago. Apparently it had stayed in the oil, continually refreshing the old seals. Because I'd used it conservatively, I had some on hand to supplement the new oil.