Does this stuff work?

[Dean924s]

I think we can all agree no matter what oil we use it is really much more important to change it regularly than to worry about all the other stuff.

[jep32]

I use Brad Penn 20-50 for film strength and added ZDDP. Engine only has 49 k on it, but very clean.

[curtisr]

Originally Posted by 333pg333

I will stick to a decent weight oil with a proper ZDDP / Detergent package and know that my engine is protected.

My understanding is that the 'high mileage' oils contain greater quantities of ZDDP than 'detergent oils' (read: low mileage). Some brands such as Quaker State make it known right on the bottle that they contain 'higher' levels of zinc. Higher, that is, than 'detergent oils'. Our 25 year-old cars were designed with ZDDP in mind whereas many of today's cars employ other materials such as titanium in order to be more cat-friendly.

Consider this from popularmechanics:

Crankshaft seals may have hardened and lost their flexibility, so they leak (particularly at low temperatures) and may crack. The higher-mileage oils are formulated with seal conditioners that flow into the pores of the seals to restore their shape and increase their flexibility. In most cases, rubber seals are designed to swell just enough to stop leaks. But the oil refiners pick their "reswelling" ingredients carefully. Valvoline showed us the performance data of one good seal conditioner that swelled most seal materials, but actually reduced swelling of one type that tended to swell excessively from the ingredients found in some other engine oils.

You also may have noticed some loss of performance and engine smoothness as a result of engine wear on your higher-mileage vehicle. These higher-mileage oils also have somewhat higher viscosities. (Even if the numbers on the container don't indicate it, there's a fairly wide range for each viscosity rating and the higher-mileage oils sit at the top of each range.) They also may have more viscosity-index improvers in them. The result? They seal piston-to-cylinder clearances better, and won't squeeze out as readily from the larger engine bearing clearances. They also may have a higher dose of antiwear additives to try to slow the wear process.

If you have an older vehicle, all of these features may mean more to you than what you might get from a full synthetic, and at a fraction of the price.


Gasoline Engines
Category Status Service
SL Current For all automotive engines presently in use. Introduced July 1, 2001. SL oils are designed to provide better high-temperature deposit control and lower oil consumption. Some of these oils may also meet the latest ILSAC specification and/or qualify as Energy Conserving.
SJ Current For 2001 and older automotive engines.

Beyond that, there's plenty more to the oil story. Read on.

Read more: How To Pick The Right Motor Oil For Your Car - Popular Mechanics

As for the synthetics, consider this bit of research done by Inengineering:

Many Porsche repair shops have acknowledged that these newest SN and CJ-4 rated motor oils are not sufficient for protecting any Porsche engine, including newer water-cooled ones. With longevity and the protection of vital engine components in mind, many shops are recommending non-approved motorcycle or racing oils, or the addition of oil supplements at every oil change, for their higher levels of protection. On newer water-cooled Porsche engines where Mobil 1 0w40 is recommended, a simple change to an oil with CJ-4 rating or preferably an oil with SL or CI-4 rating as well as a viscosity of 5w40 rather than 0w40 are two changes that can be done in addition to more frequent oil changes to ensure longevity of newer engines. Granted most of these oils will not come with Porsche approval, so if your vehicle is under warranty, defer to the Porsche approval list and select a 5w40 viscosity where appropriate over that of a 0w40, regardless of API rating, as all will carry the most recent API ratings.

[curtisr]

I guess I didn't answer the question... So, has a stop-leak done what it is supposed to for me? Absolutely, positively, without question. No hesitation. What did I use it in? An '87 924s that has crank and cam seals that need to be replaced and re-swelled. Just not necesarily in that order.

Frankly, it just stands to make sense. Our older cars require swellers that are not present in late-model oils.

[944Larry]

Originally Posted by Guest1287

Dura-Seal: Oil Stop Leak, Worlds Most Trusted Engine Oil Stop-Leak

I got a leak from my oil pan. I was wondering if this could be a temp fix till I get the $$$ to get it repaired?

Anyone ever try this method?

Yep, put it in large engines to get through a work season. It does work but I would suppose it depends on how bad the leak is. I would consider it a stop-gap and try to make proper repairs ASAP.

[Gawernator]

Brand Penn 20-50w