Gaskets & Syn vs. Dino...

[StevieC]

Anyone else seem to notice that while dino provides excellent wear protection today that it just doesn't seem to keep gaskets in the engine from hardening and/or leaking a lot sooner than synthetic?

Anyone run synthetic their whole life and can confirm this isn't the case?

From all the engines I have done work on or tore down for a rebuild I noticed this... Dino just doesn't seem to keep seals elastic/soft as well as syn's do over the same amount of miles.

 

[tig1]

I've never had a serious oil leak with synt.

 

[Garak]

That's a good question, and worthy of some thought. However, I'd say it's a pretty complex issue. We certainly have many different types of gasket materials, many different applications, and many different conditions.

I've seen engines run hundreds of thousands of miles on conventional that don't leak a drop. I've also seen engines on conventional leak like sieves. I haven't run enough synthetic to even make a personal, anecdotal comparison.

My experience with engines that don't leak for hundreds of thousands of miles on conventional are, however, a bit of a unique circumstance. Those were taxis, and did not suffer the same amount of heating and cooling cycles that an average person's vehicle might. On the taxis, the seals and gaskets could be hard as a rock, but if they don't undergo much thermal expansion and contraction, and don't undergo it frequently, it might not matter so much, with respect to sealing.

I'm sure, with respect to at least some gasket materials, some chemicals are harder on them than others, and perhaps that applies to conventional versus say a higher proportion of Group IV and V.

 

[Spector]

My 1992 camry was synthetic entire life, seals and gaskets began leaking at around 150,000, have not stopped since! Switched to dino, blends, HM no change, still leaks! Not worth repairing. Runs fine though

 

[HTSS_TR]

May be true that syn kept gaskets lasted longer than dino, but my '94 LS400 with more than 250k miles still has all OEM gaskets with mostly dino at 6-7k/6mo OCI's, it did have syn oil once in a while with 12-14k/12mo OCI's.There is no oil leak around valve cover gaskets or head gaskets.

My 10 years old 11x,xxx miles E430 with OEM gaskets has no oil leak, it has only syn oil as required by MB. It does not consumes measurable amount of oil with 12-13k/12mo OCI's even with xW20.

 

[StevieC]

I wonder if it's because Synthetics usually have more stout additive packages because people are paying the "premium" and thus more elastic softening seal additives are added to these formulations versus dino?

Or could it be because syn has substantial cleaning properties generally that make it penetrate the seals and keep them softer longer.

Maybe it's the base-stock and how it reacts with seals. PAO/Ester being easier than a convention II or II+ ???

I dunno but I thought about it today and thought I would pose the question as very rarely have I torn down an engine or replaced parts in high-mileage engines that weren't leaking with dino use.

 

[mechanicx]

I always thought PAO's were bad for seals.

 

[Doug Hillary]

Hi,
in a different environment (gearboxes and diffs) Eaton Corp in 1993 found that gearbox seals had an average replacement frequency of one seal per 150k. With synthetics this beacme zero in their test regimes

In my Class 8 trucks I found it to be even better than this - seals were never replaced through leakage (whole of life = 1.2m kms). Seals were only replaced with a bearing replacement - which was almost non existent

With HDEOs both (5W-40 v 15w40)were similar in my experience although I never replaced seals (whole of life) when using synthetic HDEOs

I have not used mineral lubricanst in my cars for many years so I don't feel "qualified" enough to comment on today's PCMOs

 

[StevieC]

Originally Posted By: mechanicx
I always thought PAO's were bad for seals.
They harden seals but most oil manufacturers of oil usually even it out with an additive to keep them soft.

 

[odie]

we have 2 YARIS with the same leaking cylinder head gasket for cylinder 1 . We're convinced it's from starting the use of 5w30 synthetic for both at around 1,200 miles ( mostly SHELL syn and 1 PLATINUM ) . The 2008 sedan has 23,000+ miles and still leaks quite a bit every 100+ miles even after the switch to Shell 5w30 conventional 3 oil changes ago covering 2,500+ miles . The 2010 3 door has had two 5w30 conventional oil changes covering 3,000+ miles and has considerably slowed or halted with checking that every 100 miles or so . Most be the longer run of synthethic for the '08 had more impact on the gasket than the shorter run for the 2010 . Just find it odd for the same leak to occur on the same engine , but few years apart after use of synthetic . Have checked several 1st generation XBs and a 2010 3 door with 35,000+ miles that belongs to an acquaintance and no leaks . He gets his oil changes of conventional at the TOYO service center and had the factory oil and filter changed at 4,000 plus miles and has kept that interval.

 

[Velo_Fello]

Here is my experience with two Mazda Miatas. Both had bad leaks from the O-ring gasket on the cam angle sensor (PITA to get to; a very rear of engine).

I put Redline Grp V ester-based oil in each. The leaks stopped.

Esters have natural seal swelling properties.

Possibly, a conventional High Mileage oil, with seal conditioners, would have done the same.

I repeated this with Royal Purple on a Saturn SL1 with leaking crankshaft seal. There was a vast improvement, but not a total cure as with the Miatas. I understand RP has around 10-15% Grp V in it.

 

[rclint]

On a speculative note how much of any gasket or seal does the oil or even more so the "elastic seal softeners" even come in contact with on any seal of gasket. This additive I assume does not penetrate seals (up to inches ???) so if it's just conditioning the surface area of the seals I can't see how a synthetic or conventional oil could effect seals much in any way as long as the oil/additives are not so called eating the seals away.

 

[Durango]

SteveC,

I've used basically M1 since past my engines intitial 3K break-in and never had to change any gaskets at all to this day with now around 85K on the odometer. I have an 01' Dodge Durango with the 4.7 liter V-8 and doesn't have any oil leaks at all. So far I'm a happy camper assuming no big truck issues arrive.

Durango

 

[mechtech2]

I think the Full Synthetic would be better for seals and gaskets, if there was any difference at all.

I have not seen or heard of a pattern either way. I kinda trust the oil mfrs to know that cars use seals and gaskets, and they are doing their best with regards to cost.

 

[StevieC]

Originally Posted By: Durango
SteveC,

I've used basically M1 since past my engines intitial 3K break-in and never had to change any gaskets at all to this day with now around 85K on the odometer. I have an 01' Dodge Durango with the 4.7 liter V-8 and doesn't have any oil leaks at all. So far I'm a happy camper assuming no big truck issues arrive.

Durango
I have used nothing but Quality Synthetics changed at proper or early intervals in my Santa Fe for the 320K KM's (192K miles) and I have had no leaks. Now it's only been 5 years since I racked up these miles and most are easy highway miles. So it may not be the synthetic at all but the driving patter or engine design or short time I have had the vehicle.

What I have noticed is the majority of the cars dad and I work on that have run Dino have leaking seals of some sort after 150-200K KM's (90K - 120K miles).

 

[RacerE7773]

My LIM gasket is bad, otherwise I would use synthetic in the Impala. Cannot afford to get it fixed yet.

 

[StevieC]

Originally Posted By: RacerE7773
My LIM gasket is bad, otherwise I would use synthetic in the Impala. Cannot afford to get it fixed yet.
Just ARX it or add MMO, it fixes everything...

 

[Durango]

StevieC,

It's possible that dino turns acidic as it ages during normal driving. The longer you have it beyond it's ful duration the more it eats gaskets and such because of the acid type oil.

I wonder????

Durango

 

[Bill in Utah]

Originally Posted By: StevieC
Originally Posted By: Durango
SteveC,

I've used basically M1 since past my engines intitial 3K break-in and never had to change any gaskets at all to this day with now around 85K on the odometer. I have an 01' Dodge Durango with the 4.7 liter V-8 and doesn't have any oil leaks at all. So far I'm a happy camper assuming no big truck issues arrive.

Durango
I have used nothing but Quality Synthetics changed at proper or early intervals in my Santa Fe for the 320K KM's (192K miles) and I have had no leaks. Now it's only been 5 years since I racked up these miles and most are easy highway miles. So it may not be the synthetic at all but the driving patter or engine design or short time I have had the vehicle.

What I have noticed is the majority of the cars dad and I work on that have run Dino have leaking seals of some sort after 150-200K KM's (90K - 120K miles).


And I've run mostly Conventional run at longer OCIs (my last one was over 11,000 miles) and not a single seep of oil anywhere at 180,000 miles in the Corolla (coming up).

My Jetta saw nothing but yesterdays conventional oils and had a slight leak towards its end on the valve cover starting around 350,000 miles.

It does not MATTER what type of oil you run in my book. Some engines leak and others do not.

 

[Merkava_4]

My seals and gaskets stay nice and soft using Maxlife.

It's the equivalent of using Downey on bath towels.