German Castrol 0w-30?

I have heard nothing but good things about this oil, it is used in my girlfriends BMW and it runs very nice. Would it hurt my Blazer to run 0w-30? I use Mobil 1 now but it makes my rear main leak. I know everyone will tell me it isn't the oil, but I had the seal replaced professionally and it still leaks, but only with the Mobil1. Maybe I need an oil that will swell my seals up a bit better. Suggestions guys?

What viscosity of mobil1 are you using?

I am using 5w-30 right now.

I would only use 0W-30 of any oil ifit was the dead of winter and the temps were constantly well below freezing for our trucks that are supposed to have 5W-30 in them. I can tell you that after a few oil changes with Mobil1 after using crap Dino my oil leak got worse for an oil change or two and then completely dissapeared. I am a firm believer in using Mobil1 and will not switch. If you still feel compelled to use Castrol make sure you use the bottles that say made in Germany on the back, if you don't, I believe the ones that say made in America are not true synthetics. Now don't qoute me as I might be wrong here but I do believe Mobil1 is the best. Plus you can buy it in the 5 quart jug for under $20 at Walmart. You can't beat that!!!! And as always make sure to use nothing but an Ac Delco, Wix or Napa, oil filters, stay away from Fram. Good luck and let us know what happens.

Does GC come in 5 or 10w-30? I am just sick of this stupid seal dripping. I also heard that since Mobil1 isn't derived from ester it doesn't swell the seals as well as it should because it doesn't have the best additive package. Any thoughts on this?

I would only use 0W-30 of any oil ifit was the dead of winter and the temps were constantly well below freezing for our trucks that are supposed to have 5W-30 in them. I can tell you that after a few oil changes with Mobil1 after using crap Dino my oil leak got worse for an oil change or two and then completely dissapeared. I am a firm believer in using Mobil1 and will not switch. If you still feel compelled to use Castrol make sure you use the bottles that say made in Germany on the back, if you don't, I believe the ones that say made in America are not true synthetics. Now don't qoute me as I might be wrong here but I do believe Mobil1 is the best. Plus you can buy it in the 5 quart jug for under $20 at Walmart. You can't beat that!!!! And as always make sure to use nothing but an Ac Delco, Wix or Napa, oil filters, stay away from Fram. Good luck and let us know what happens.

The 0w30 can be used all year around.

The German Castrol 0w30 technically is thicker than the Mobil1 5w30 which is why you can only compare 5w30 to 0w30 within the same brand and type.

http://x10.putfile.com/3/8217410522.gif (http://www.putfile.com)

Here you can see the difference in viscosity between the two and many others.

They are both 30 weights at operating temperature which is the crucial point. I use 0w30 all year around and you won't find a better all temperature oil.

Thanks LT. Also, I notice you are quite active on the oil drop forums, what is your take on Mobil1 seal conditioning properties. This is the only oil that leaks out of my truck, mostly the rear main which is brand new. Should I give the GC a try?

Thanks LT. Also, I notice you are quite active on the oil drop forums, what is your take on Mobil1 seal conditioning properties. This is the only oil that leaks out of my truck, mostly the rear main which is brand new. Should I give the GC a try?

Scomp23, if the rear seal is leaking after it was replaced, you should take it back to them and have them fix it. You don't pay good money to have an improper job done.

Also, replace your PCV valve and clean both the fresh air and PCV lines out. This will rule out elevated crankcase pressures causing the leak and pushing the oil out the seals.

Mobil1's PAO based Group 5 baseoil should not cause leaks. In some or most cases, when it causes a leak, it will stop it within 10,000miles seeing after it cleans the crud that was causing a false seal, the additives will quickly plump the seal back up.

I think this is a bad seal that was installed if it didn't stop it.

Thanks a lot LT, I have only driven for 3k miles or so with the Mobil 1. The GC won't hurt my truck will it? 0w-30 is perfectly fine? I think it is the 30 that I should be concerned with right, as that is the thickness at operation. Will the 0w give me enough protection at startup?

Thanks a lot LT, I have only driven for 3k miles or so with the Mobil 1. The GC won't hurt my truck will it? 0w-30 is perfectly fine? I think it is the 30 that I should be concerned with right, as that is the thickness at operation. Will the 0w give me enough protection at startup?

http://x10.putfile.com/3/8217410522.gif (http://www.putfile.com)

As you can see above, the 0w30 Castrol is actually a bit thicker at any given temperature than the Mobil1 5w30.

You will have the EXACT same protection on startup or even better. You see, the X in XwYY is not a weight at all, it is a cold flow number and everyone knows that there is not a zero weight oil which means the oil would not be there.

0w30, 5w30, 10w30 in THE SAME BRAND AND TYPE of oil are all 30 weights at operating temperature which is 100c or 212f. The only difference is that the lower the number at the front, the lower the temperature the oil can take before it gels and hits its' pour point.

Now you have to consider that you are NOT comparing apples to apples here. You are comparing two different manufacturers oils at two different grades and they are not directly comparable.

Here let me show you numbers extracted from the chart above:

GC 0w30

-20c: 2609cst
100c: 12.0 cst

M1 5w30

-20c: 2225.1 cst
100c: 10.0cst

So there you can see why you cannot directly compare two different manufacturers oils and different grades. The GC 0w30 is actually thicker than the M1 5w30 at -20c.

Where can you Buy German Castrol 0w-30 Oil at? How expensive is it?

Autozone here in the states, its the same price as American Castrol Syntec

Where can you Buy German Castrol 0w-30 Oil at? How expensive is it?

Should be around the same price as all the other synthetics.

You have to turn the bottle over and look at the back and see if it says "Made in Germany"

There is a 0w30 USA version but it isn't as sought after or as good.

It is the ONLY syntec that is actually synthetic, all the rest are hydrocracked conventional oils and are not a true synthetic.

Thanks for the info LT

Well I am going to make the switch tomorrow from M1 to GC, I will let everyone know how it goes.

I use it, and abuse it for 12,000 miles at a time in my truck engine. No problems or troubles yet. I change filters according to the manual's severe duty cycle and top off any oil lost in the filter swap. She does not burn or consume this oil not one bit and runs like buttered silk. Cannot go wrong at all on GC 0w-30. Period. And if you're lucky - you'll find the GREEN German Castrol. If not, batches made from '05 to date will be amber - but the stuff is just as good as the good old green. I have over 80 quarts of the stuff stocked up for my truck, the roommate's Minivan and whomever else who gets curious. I gave a gift of 5 quarts of this stuff to my little brother and he's hooked - searching every Autozone oil rack he comes to. :D

I use it, and abuse it for 12,000 miles at a time in my truck engine. No problems or troubles yet. I change filters according to the manual's severe duty cycle and top off any oil lost in the filter swap. She does not burn or consume this oil not one bit and runs like buttered silk. Cannot go wrong at all on GC 0w-30. Period. And if you're lucky - you'll find the GREEN German Castrol. If not, batches made from '05 to date will be amber - but the stuff is just as good as the good old green. I have over 80 quarts of the stuff stocked up for my truck, the roommate's Minivan and whomever else who gets curious. I gave a gift of 5 quarts of this stuff to my little brother and he's hooked - searching every Autozone oil rack he comes to. :D

lol, that is a lot of oil my friend. I just bought some today, will be doing my oil change shortly with a Napa Gold (Wix) filter. The bottles I got not only say Made in Germany, but also say "European Formula" on the front now as well.

Yeah, that's the post Katrina labeling that's come in recent batches from Castrol, and will be Amber in color. The real treat when you find the green stuff is that is smells like something you can drink - almost like Gummi Bears. It also is radiator fluid green in color, so it *will* tweak the head of your mechanic/Service tech. Keeping a half quart left over from a 4.5 quart fill for my engine in the back provides proof that you do not have anti-freeze in your crankcase. And who knows, you might turn another person over to the "Dark side" of oils. Wix is a good choice with this oil. Swap that filter out every 3-5K if you are a short trip driver with 5k mile oil changes. Or if you are a commuter, averaging long, lazy highway miles, swap filter every 7-9k with 12k mile oil changes with this marvelous oil.

Too funny WOLFOX. SComp let us know how it goes!!!

Well I made the switch, and so far, so good. The first MAJOR thing that I noticed was my engine was noticably more quiet. Mobil1 has a tendency to cause a louder engine in several vehicles, something you don't really notice after you have been running it for a while. I think I will let this cycle go for 5k miles and send away a sample for an oil analysis to see what's going on in there.

Well I made the switch, and so far, so good. The first MAJOR thing that I noticed was my engine was noticably more quiet. Mobil1 has a tendency to cause a louder engine in several vehicles, something you don't really notice after you have been running it for a while. I think I will let this cycle go for 5k miles and send away a sample for an oil analysis to see what's going on in there.

Go for 5000miles and drop a small sample and send it away and keep the oil in the pan.

That oil is good for far past 5000miles.

hey here my experience with Mobil 1 0-30w motor oil..
I made the swith last winter and notice that my MPG went up to 14.9...
then when i switch back to 5-30w in the summer its 14.6...
the mpg was read of the digital display in the car..

I don't know if it was becasue of the winter that i saved gas or if it was the 0-30w oil, but i am planning to switch back to mobil 0-30w this summer...

i prob, don't need an oil change but i have nothing better to do haha

and yeah the engine sounds a lot more quiet and smoother with the 0-30w oil

Don't go by the digital display, they are never correct, plus you drive harder in the summer ;) Fill up your tank and reset your trip, go as much as you want and then refill. When you refill divide how many miles you went by how many gallons you put in. That will give you average of all driving, whether it be city and highway or all. I am sure you knew all of this so I don't want you to take offense, I was just restating.

Yip, never go by the digital read out, it isn't really accurate.

SHIT!!!:banghead: haha BlazerBoy i've mever thought of that, for real... ever since the fuel gauge gone bad i just reFill the gas whenever i feel its going out..

wow, now i just gotta grab a pen and log and start writing how many gallons of gas i get everytime i get gas...

and this is why i think the Digital Display is pretty accurate...
I reset the odometer, and on the digital display it shows mpg and gallons of gas used. So if the MPG say 14.6 and gallons of gas used say 0, i would reset the odmeter to 0, and once the odometer reads 14.5 ish and gallons of gas used say 1, i know i got a pretty good estimate

There you go foon, learn something new everyday ;)