BMW synthetic 5w-30 vs German Castrol

[m6pwr]

I'm a newbie on the forum and am trying to absorb as much info as I can - - and there is an amazing amount of oil info on this forum. I've read through the threads on GC, in general, and BMW's synthetic 5w-30. I have a '02 330i zhp 6 speed and have been using the BMW 5w-30 with OCI of about 4000 mi. I do a wear metals UOA and have gotten pretty low readings; e.g. 7 ppm copper, 5 ppm iron, 4 ppm aluminum, 3 ppm lead, and not much shear back- - it stays in grade.

As far as I can determine, the BMW oil is ACEA A3/B3 rated, is formulated at the heavy end of the 30 wt spectrum (like GC), is a grp 4 PAO, and (judging from some of the UOA I've seen on the forum) has about the same zddp concentration as the GC: 800-900 phosphorus and zinc.

My question is this: would there be any advantage in switching to the GC? I know the GC is very highly thought of on this forum. I live in San Diego, so cold starts are not a concern.

 

[jaj]

Welcome to the board!

Given your UOA results and the short change intervals you're getting great performance from the BMW product. While you'll get a lot of posts recommending that you switch to something else, you've got a great engine that's doing just fine with the oil you're using.

 

[Craig in Canada]

GC is supposedly superior to the BMW 5W30, but the BMW stuff isn't bad especially at your intervals.

I've seen people claim that their UOAs are good even at the manufacturer extended intervals. I've also seen machines maintained on this interval that are a varnished, sludgy, filthy mess.

Over the years I've concluded (for myself) that the BMW stuff offers good wear protection but isn't very "clean" after 7kmi or so and starts to make a mess of things even though the wear numbers are still good.

 

[jpr]

Both are certainly good.

Additive-wise, biggest difference seems to be that the BMW has about a 125 ppm dose of Moly, about 50 ppm Boron, and no Mag. GC has basically no Moly or Boron but about 125 ppm Mag. Z and P levels are similar.

UOA results on M54 engines are similar, but with perhaps very slightly lower wear rates with the GC. The BMW seems to stay a little thicker than the GC. TBN depletion rates seem similar.

All in all, they are rather similar oils, certainly too similar for anybody to accurately predict a significant difference. I think the only real reason to switch would be for the pure fun of experimenting.

 

[Quattro Pete]

Originally Posted By: m6pwr
My question is this: would there be any advantage in switching to the GC?

Unlikely. Your OCI is very short and your wear is low. It'd be difficult to improve on these numbers. And even if you can reduce wear by an additional 1 or 2 ppm, it's not going to matter for the longitivity of your engine.

 

[Jim 5]

Originally Posted By: Quattro Pete
Originally Posted By: m6pwr
My question is this: would there be any advantage in switching to the GC?

Unlikely. Your OCI is very short and your wear is low. It'd be difficult to improve on these numbers. And even if you can reduce wear by an additional 1 or 2 ppm, it's not going to matter for the longitivity of your engine.



Agree.

The BMW stuff is very good in my opinion. While it is no GC, it has shown the remarkable ability in UOA results to cope at 15k miles. It is definitely designed for euro-style long OCI's. I think its a "sleeper" oil that doesn't really get its due here.

 

[cosynthetics]

The BMW oil (I believe) is a Group III and not a Group IV like GC. It's not regarded quite as highly on this forum as GC.

With that said....
I've used it in the past and have owned two cars that ran it on the factory 15k intervals and neither have sludge. It is cheaper than GC. For short intervals you are probably fine but if you have a GC supplier closer or want to run longer intervals I'd go with GC or another BMW LL oil.

Here's a BMW LL thread if you want oil recommendations for your car.
http://forums.bimmerforums.com/forum/showthread.php?p=12130329

 

[docvb]

Am I the only that does not like the BMW synth oil? Although everyone says the same thing, " this is good, this is a sleeper, the stuff is robust...."

Have you ever seen the stuff?

It has a red-like tint (yes, it stains) that is obviously cosmetic (and therefore distrusted) and is very jell-like, most unlike any other synthetic oil I've ever had experience with. It is certainly unlike any 5W-30 oil and quite unlike GC.

And then there's the sludge issue. You figure that most of the sludged cars were running the synthetic bmw lube.

And then there's the cost issue. The stuff is cheaper at a BMW DEALERSHIP than real synthetics at WALMART. This suggests to me that the actual product value is 40 cents a quart to the BMW stealership. No way this is a quality product.

Anyone else with these same suspicions?
\

 

[cosynthetics]

Originally Posted By: docvb
Am I the only that does not like the BMW synth oil? Although everyone says the same thing, " this is good, this is a sleeper, the stuff is robust...."

Have you ever seen the stuff?

It has a red-like tint (yes, it stains) that is obviously cosmetic (and therefore distrusted) and is very jell-like, most unlike any other synthetic oil I've ever had experience with. It is certainly unlike any 5W-30 oil and quite unlike GC.

And then there's the sludge issue. You figure that most of the sludged cars were running the synthetic bmw lube.

And then there's the cost issue. The stuff is cheaper at a BMW DEALERSHIP than real synthetics at WALMART. This suggests to me that the actual product value is 40 cents a quart to the BMW stealership. No way this is a quality product.

Anyone else with these same suspicions?
\


I agree with you. I just stated that I think it is fine with short OCIs.

I don't think it even meets BMW LL specs does it? Anyone have a recent bottle to look at?

 

[Jim 5]

Originally Posted By: docvb
Am I the only that does not like the BMW synth oil? Although everyone says the same thing, " this is good, this is a sleeper, the stuff is robust...."

Have you ever seen the stuff?

It has a red-like tint (yes, it stains) that is obviously cosmetic (and therefore distrusted) and is very jell-like, most unlike any other synthetic oil I've ever had experience with. It is certainly unlike any 5W-30 oil and quite unlike GC.

And then there's the sludge issue. You figure that most of the sludged cars were running the synthetic bmw lube.

And then there's the cost issue. The stuff is cheaper at a BMW DEALERSHIP than real synthetics at WALMART. This suggests to me that the actual product value is 40 cents a quart to the BMW stealership. No way this is a quality product.

Anyone else with these same suspicions?
\


Have I ever seen it? Sure...seen it, used it, UOA'd it, had UOA results analysed by a well respected professional. You... "it looks very gel-like".

Apart from that observation, I'm not sure what you're basing your suspicions upon, but that's the problem with suspicions. My statements are based upon reviews of UOA's on this site (using the search function, you can too), my UOA's, and Terry Dyson's comments on my UOAs.

BMW Synthetic is known to be Castrol Softec TXT 5w-30, which is not a cheap oil. It is not marketed outside BMW dealerships in North America. If you were going to buy it in Europe, you'd likely pay well over $20/L.

Also, I'm not sure why it would be suggested that BMW would recommend and bottle its own oil if it didn't meet its own LL-01 spec. However, if you have any doubt, here is the product specification on Softec TXT:

http://www.castrol.com/liveassets/bp_int...1_B1567_02.pdf.

Finally, the sludged bmw's I'm aware of missed a few oil changes. Missing a few oil changes in this context means they went close to 50k miles on one fill of oil.

I choose GC because its about the same price as BMW dealership oil, and its cold properties are better. I don't think you'd see much difference in UOA's even at 10k miles between the two. I would say the same thing between GC and RTS 5w-40....again, based on UOA's.

 

[Jim 5]

Ps...Welcome to the Board!

My apologies if my reply seemed snarky. In reading it I can see it could be interpreted that way. It was not the intention, and that is not the culture here.

 

[m6pwr]

Jim 5: thanks for the welcome aboard and no offense taken at all; and thanks to all for their input, both pro and con. I find the subject of motor oil a fascinating subject, but I know it's one that can generate intensely personal views sometimes.

 

[bmwtechguy]

I would confidently go 7-10k miles on either of those oils, of course, unless all short tripped around town: then I would keep to your current practice of 4k miles or maybe go 5k miles.

 

[Jim 5]

Originally Posted By: Jim 5
Ps...Welcome to the Board!

My apologies if my reply seemed snarky. In reading it I can see it could be interpreted that way. It was not the intention, and that is not the culture here.


...to docvb as well

.

 

[KenO]

Originally Posted By: Jim 5
Originally Posted By: docvb
Am I the only that does not like the BMW synth oil? Although everyone says the same thing, " this is good, this is a sleeper, the stuff is robust...."

Have you ever seen the stuff?

It has a red-like tint (yes, it stains) that is obviously cosmetic (and therefore distrusted) and is very jell-like, most unlike any other synthetic oil I've ever had experience with. It is certainly unlike any 5W-30 oil and quite unlike GC.

And then there's the sludge issue. You figure that most of the sludged cars were running the synthetic bmw lube.

And then there's the cost issue. The stuff is cheaper at a BMW DEALERSHIP than real synthetics at WALMART. This suggests to me that the actual product value is 40 cents a quart to the BMW stealership. No way this is a quality product.

Anyone else with these same suspicions?
\


Have I ever seen it? Sure...seen it, used it, UOA'd it, had UOA results analysed by a well respected professional. You... "it looks very gel-like".

Apart from that observation, I'm not sure what you're basing your suspicions upon, but that's the problem with suspicions. My statements are based upon reviews of UOA's on this site (using the search function, you can too), my UOA's, and Terry Dyson's comments on my UOAs.

BMW Synthetic is known to be Castrol Softec TXT 5w-30, which is not a cheap oil. It is not marketed outside BMW dealerships in North America. If you were going to buy it in Europe, you'd likely pay well over $20/L.

Also, I'm not sure why it would be suggested that BMW would recommend and bottle its own oil if it didn't meet its own LL-01 spec. However, if you have any doubt, here is the product specification on Softec TXT:

http://www.castrol.com/liveassets/bp_int...1_B1567_02.pdf.

Finally, the sludged bmw's I'm aware of missed a few oil changes. Missing a few oil changes in this context means they went close to 50k miles on one fill of oil.

I choose GC because its about the same price as BMW dealership oil, and its cold properties are better. I don't think you'd see much difference in UOA's even at 10k miles between the two. I would say the same thing between GC and RTS 5w-40....again, based on UOA's.


http://www.performingimports.com/maint.htm

Take a look at the pictures to the right. I'm familiar with that shop personally, The owner is an automotive engineer, came here from Germany, and was formerly an employee of Mercedes Benz in Germany. The majority of these engines sludge with the BMW oil taken to the SI light recommendation. Unfortunately, it's not very consistent, some engines do, some simply don't. I think it also has to do with the way the vehicle is driven as well. These engines like being driven hard, it's what they were designed for.

 

[cosynthetics]

I don't think this is as common as what some think. There's one or two cases of this that keeps getting spread. I've had 2 540s that were dealer maintained and neither show any sign of sludge.

As far as the SI, I've put over 20k miles before with it only moving two blocks.

 

[JAG]

My mother owns a sludged 1999 BMW 328i. The first owner's maintenance is unknown but he was a doctor (probably had dealer change the oil when told to).

My coworker recently got done owning a sludged 2000 (or so) BMW 328i (or 330i...?) that used dealer BMW 5W-30 with 15K mile OCIs.

That's two more cases of sludge for the record.

 

[cosynthetics]

Any pics?

 

[JAG]

No pics but I do have some good descriptions of the deposits in my mother's BMW 328i here: http://www.bobistheoilguy.com/forums/ubb...true#Post812589

My coworker's BMW was totaled recently while parked along a road at a car service station and it was there for a rapid oil leak. I can't get pics of it now. It was a little more filthy looking inside the oil fill cap area than my mother's BMW.

 

[Jett Rink]

I am currently driving one that had three 15,000 mile oil change intervals before I got hold of it. A peak inside the oil fill hole at the internals reveals...well, nothing, because the view is obscured by a black plate.

The oil had just been changed with BMW Castrol 5w-30. So I poured a bottle of Auto Rx in there. I drove it 2,650 miles and then put in Chevron Supreme dino as a rinse oil. A mix of 5w-30 and 10w-40. No in depth calculations there, it is just what I had sitting around in my garage and wanted to get rid of it. The oil filter looked fine. No evidence of sludge or anything, but oil.

Incidentally, I'm noticing no difference whatsoever in mileage, startup or driveability with the cheap Chevron dino oil. Maybe such a combo is just fine for 3,000 mile OCIs?

I have driven about 2,700 miles with this rinse. Sometime later in the week I'll hit 3,000 miles and will change. If the filter reveals anything worth photographing, I'll take a picture of it, for the sake of science. If my wife catches me photographing a used oil filter with her fancy digital camera, she will most likely think I have gone completely nuts, so I'll have to be sneaky.

Anyway, this will be just one more test of BMWs 15,000 OCIs.

There is a red-orange colored stain around the lip and the underside of the oil fill cap. I think this is defnitely a byproduct of the BMW Castrol oil. It seems to be quite common. But I rubbed it with a little oil on my fingertip and it came right off very easily.

Stay tuned for Auto Rx results.