GC and its effect on seals

[Vaca]

I understand that PAOs are hard onoil seals, makes them shrink or something, and esters or something else is mixed to ameliorate this problem.

My question: what long term effect does using GC have on the durability of engine seals?

I just bought a nice used 2004 BMW 530i and I want to use the best reasonably priced oil and I want to run this car forever an d I hate oil leaks in my garage or in my driveway so this question is not just theoretical.

Does anyone have any insight into this? Thanks in advance.

 

[moribundman]

I don't believe you will find any modern engine oil that will be detrimental to the seals. If you are concerned, stick with an oil spec recommended by the car manufacturer. Seal compatibility is part of oil spec approval.

 

[Drivebelt]

PAO and the problems with seals was only generally an issue with some older vehicles (12 years +) and the particular seal materials used. Also, many older synthetics probably weren't as balanced with seal swell (esters) to counteract the PAO's.

In a modern vehicle with modern synthetic oils and better seals, I'd say it’s basically almost a non-issue these days. I would use GC or any synthetic oil in that 2004 BMW without worry.

 

[UncleRunkle]

My Jag and Caddy have been on GC for a combined 30,000 miles with zero leakage.

 

[Quattro Pete]

Originally Posted By: Vaca
My question: what long term effect does using GC have on the durability of engine seals?

GC carries BMW spec approvals. It will not harm your engine. BTW, I use it in my 530i as well. No issues. I did have to replace a valve cover gasket, but this is not related to the type of oil used. Gaskets on these engines tend to become brittle, crack, and start leaking with age, regardless what oil is used. Shame on BMW to botch this design... mine only lasted 50k miles.

 

[Volvohead]

Originally Posted By: Vaca
I understand that PAOs are hard onoil seals, makes them shrink or something, and esters or something else is mixed to ameliorate this problem.




Only the very earliest of full synthetic oils exhibited this problem, and it was as much a result of the then prevailing seal technology as it was the oil.

You are correct that most Group IV PCMOs now have some combination of base oil components that alleviate seal reactions. But seal design and composition have also dramatically improved. Today, seal shrinkage from Group IV oils is a complete non-issue on a modern engine.

Any seal leaks on a modern engine that do develop after use of synthetic oils are almost exclusively due to partial cleaning of contaminated and/or worn seals.

Bottom line: unless your engine is from the early '70s, you can use a modern G-IV oil with complete confidence as far as seal shrinkage is concerned.

If you do have a nagging leak concern, then ARX the engine beforehand.

 

[rg200amp]

I will +1 the notion that todays seals and synthetic oil for that matter are much better than the ones in the past. I do believe that issue is not valid anymore.

Futhermore. . . .

The BMW house oil is a Group IV oil I believe. So the BMW engine is spec'd to use a PAO oil.

GC is a great oil, you will see great results.

 

[Vaca]

Thanks to all, I will continue with the GC, but will certainly change more often than the crazy-long miles (15,000 or so) that the oil monitor suggests.

I'm thinking to change it approx halfway, at 7500, but then reset the monitor each time I change the oil.

 

[double vanos]

I have used GC in my '02 330ci for over 60k miles and she's as dry as a popcorn f(a)rt.

I was using Mobil 1 0w40 but changed to GC with no regrets.

The car is currently at 125k and zero oil consumption.

Here's how I use my oil monitor..

When I reset it after an oil change, it counts down from 15,250 miles.

I change oil again at 10,000k and then at 5,000 and then at 0. Reset the OLM.

Works out to about 5,200 miles each change.

Perfect.

 

[RI_RS4]

It just makes a mess of them.

 

[Quattro Pete]

Originally Posted By: double vanos
When I reset it after an oil change, it counts down from 15,250 miles.

How can you display this info? I can display the amount of fuel consumed since last reset on mine, but not miles.

 

[shanneba]

When I turn on the ignition on my 03 330Ci it shows the miles to service just for a few seconds.

 

[Vaca]

Originally Posted By: Quattro Pete
Originally Posted By: double vanos
When I reset it after an oil change, it counts down from 15,250 miles.

How can you display this info? I can display the amount of fuel consumed since last reset on mine, but not miles.




On my 04 530i, I go to the info screen on iDrive and go to vehicle maintenance and it shows the miles remaining to all of the items...like front brakes, rear brakes, oil, etc.

Not sure if the 02 530i has an iDrive???