Best oil leak stop products?

[FTTSHO]

Got a 4.3 vortec that is leaking some oil. It’s been leaking oil since I bought it 2 years ago, and the oil leak has not gotten any worse.

I do 3k mile oil changes and I do not notice any oil level dropping on the dipstick, so it’s not a severe oil leak.

The timing cover seal seems to be leaking a little, the oil pan gasket also seems to seep a little oil, and the rear main seal is leaking a little as well. I never get any oil spots on my driveway, so it’s not a huge leak.


I obviously know the best and the most effective way to stop this is to replace the old gaskets, but on my 4x4 blazer, it’s a pita to remove the oil pan. It’s not worth removing the whole front differential and all the oil lines that goes along the pan.

So, what are some good products I could use in the engine to maybe slow down or stop the oil leak? What is the best oil that can stop or slow down minor leaks here and there?

Thanks!

 

[TmanP]

Are you using a high mileage oil already? My first step would be to try something like Maxlife.

 

[JavierH19]

Someone had good luck in stopping a drip using high mileage Pennzoil conventional which home depot sells in store so I'd go there for a jug of 10w-40.

 

[FTTSHO]

Are you using a high mileage oil already? My first step would be to try something like Maxlife.

I’ve used high mileage Mobil 1 before, and it didn’t do anything for me. Would Maxlife be a better choice?

 

[SC Maintenance]

Someone had good luck in stopping a drip using high mileage Pennzoil conventional which home depot sells in store so I'd go there for a jug of 10w-40.

^^ This.

What are you using now? Try a conventional. I like the Havoline 10W-40 in the box, but any conventional would be good for a test before you start trying the snake oil.

 

[BobsArmory]

I have had great luck with Blue Devil stop leak in my daughters junker. Usually available at Walmart and misc auto part stores.

 

[CarlB]

If fixing isn't an option, then I'd rather just top off than try to liquid mechanic.

 

[wlk]

I’ve used high mileage Mobil 1 before, and it didn’t do anything for me. Would Maxlife be a better choice?

I've had good results from red bottle Maxlife slowing/stopping a leak. Never had a Mobil High Mileage slow/stop any leak either.
Try LiquiMoly Motor Oil Saver if you want an additive, works well too. Just snagged 12 bottles off Amazon for 20 bucks.

 

[CarGuy23]

I agree - BlueDevil Oil Stop Leak works fast and very well. I am not sure what is in it but it works

 

[Mainia]

I’ve used high mileage Mobil 1 before, and it didn’t do anything for me. Would Maxlife be a better choice?

My daughters old Honda was a "a leakier" Mobil 1 High Mileage did almost nothing, just a bit. Pennzoil High Mileage synthetic stopped the leaks almost fully. And it was a leakier. It took about 2 month+ to stop it.

 

[Johnny248]

ATP AT-205 ftw if it's a "rubber" seal. This stuff actually works. I've used in engine, trans, and p/s. Follow the directions, give it a couple hundred miles. If it's an RTV leak or dumping a quart a day, it isn't going to fix anything. If it is a small leak from some sort of seal, it's as good as it gets.

 

[gamefoo21]

ATP AT-205... It's expensive but it works. At least on hardened rubber seal type leaks, and from my experience it seems to help on valve covers. I went from a weeping valve cover to a not weeping. Though that might have been a super lucky draw. Also it worked on the transmission cooler lines on the inlaws Equinox.

With AT-205 though it does kinda not like to stay mixed into most oils, so I tend to add it and let the engine idle for 10-15 minutes or go for a cruise after adding it, to help get it spread around. Maybe it's the chicken noodle soup type of herbal knowledge, but it seems to work for me.

One thing, I've heard of some bad results with Blue Devil for Power Steering, in an older Volvo. It caused the steering to become sticky feeling and sort of poppy.

My daughters old Honda was a "a leakier" Mobil 1 High Mileage did almost nothing, just a bit. Pennzoil High Mileage synthetic stopped the leaks almost fully. And it was a leakier. It took about 2 month+ to stop it.

I think Mobil 1 High Mileage is one of the thinner High Mileage oils while Pennzoil High Mileage is on the thicker side, so that might have been the decider.

 

[50yr Street Mech]

AT-205 for seals that are not RTV. It even stopped a valve stem seal leak on my old Toyota. Nothing will stop an RTV leak, except taking it all apart and re-sealing.

 

[AdmiralYoda]

My old Toyota 22RE is burning oil. 90% sure its valve seals though I don't have any smoke at startup no matter how long it sits. I'm going to be giving AT-205 a shot at the next oil change. Can't hurt to try. I'll probably mix it with some 10W-40 HM.

It is available at my local Advance Auto Parts for about $2 more than amazon.

 

[dadto2]

I'd put a big piece of cardboard on the garage floor and top it up once in a while.

 

[50yr Street Mech]

Bad valve stem seals ALWAYS smoke on start up, then burn off in a minute or so. You may have stuck rings causing oil burning. Try BG PN 109 next oil change. A few rounds of that stuff cleaned up the pistons in my old Honda. Or, you can try a piston soak.

 

[AdmiralYoda]

Bad valve stem seals ALWAYS smoke on start up, then burn off in a minute or so. You may have stuck rings causing oil burning. Try BG PN 109 next oil change. A few rounds of that stuff cleaned up the pistons in my old Honda. Or, you can try a piston soak.

My thoughts exactly. I've done two B12 soaks and a BG109 flush and it didn't help much. The truck did sit for 5+ years twice without starting, I'm wondering if the cylinders and/or rings are worn.

It tends to burn the most oil (I can smell it) when compression braking and pulling a strong vacuum.

One of these days I'll do a leak down and compression test then stick a camera down into the cylinders to see how things look. Aside from burning oil it runs great!

 

[50yr Street Mech]

Just stored an 06' Toyota Camry with the 2AZ-FE engine in it. Won't be started in 3 years until my daughter gets her license. Has new oil and filter in it, Stabil Storage in the full tank, moth balls packets all inside the engine bay to keep the mice away, plugged the exhaust with stainless steel wool, a NOCO 2 genius on the battery, anti-flat spot ramps on the new tires, and a pretty expensive outdoor cover. Ran a BG 109 before the oil change. Buttoned up good. Not starting it either. Sitting under my deck on asphalt, shaded from the sun. Hoping that don't start burning oil in 3 years. Wish me luck.

 

[rszappa1]

ATP 205...

 

[wlk]

I agree - BlueDevil Oil Stop Leak works fast and very well. I am not sure what is in it but it works

Blue Devil helped stop an pinion seal leak on our front diff that had popped up while traveling across the country. We left Iowa and in 2 days got to Erie, PA and it had stopped thankfully.