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During that first 1,500 miles I drive easy, except for an occasional hard acceleration (not more than 3/4 throttle) after a full warmup (20 minutes of driving) to help seat the piston rings.
I think 5,000 miles is stretching it with a dino oil. Even if I were going to run dino oil, I'd do the first oil change at 1,500 and then at 3,000, 6,000 etc.
With synthetic, I change at 1,500, then at 5,000, then every 5,000 miles.
I haven't decided whether to change from regular formula Mobil 1 to the Extended Performance formula. I don't care about the extended drain interval on Mobil 1 EP so much as their use of antiwear additives of types, and in quantities, which are now prohibited by the new API SM formulation requirements. There is some controversy among enthusiasts as to whether the oil companies are being forced to trade off engine protection vs. catalytic converter protection. Personally a catalytic converter is cheaper for me to replace than an engine, but I haven't made a final decision yet.
For warranty purposes, you need to check the owners manual and see what grade and what API classification is required for your new Mazda, pick a brand of oil you like, then check their website and read the bottle carefully.
A lot of us here use dealers to change our oil, but carry in our own preferred brand of oil.
Always remember that every oil is "tagged" so that its maker and formulation can be identified with an oil sample. This is so manufacturers and oil companies can handle lubrication related engine failures. Also keep in mind that you need clean documentation - who did the lubrication services and what lubricants were used - to maximize trade-in and resale value.
I switched to 5w-30 M1 on my used accord at 113k(leaked alot, turned black quickly, and idled loudly in the beginning). Now it has 132kmiles. I think turning black quickly is probably a good thing since it's cleaning out alot of junk.
Switched to M1 on my used maxima at 50k miles, (no leaks, turn black, and also idled loudly). Decided to switch back to conventional at 60k miles. Idle noises gone!
I can think of two possibilities, one, because m1's very thin oil is probably blow passing through the pistons? Two, the thick havoline oil 5W-30 i used.
Im not saying m1 is a negative oil (still will use it for my new truck), just wondering about its thin formulation and how it would affect the pistons or friction?
Can anyone share some light to this?
High
You might try using either 0-40 M1, which is a European formula for VW's etc. which is closer to 0-35, or 5-40 M1, which is more of a true 40 weight.
However, all this begs the question of why a 50k Maxima is so sensitive to oil weight. For example, I ran 0-40, 5-30, 5-20, and 20-50 in a 2001 VW Golf I bought new which called for 0-40; all oils ran the pretty much the same,without lifter or other noise, except the 20-50 dropped in gas mileage, and oil consumption went up slightly on the 5-20. According to oil company representatives, most cars can use a range of viscosities.
Is there any chance the noise is a startup noise related to the anti-drainback valve in the oil filter? I got a bad oil filter once and it made my Neon noisy on initial startup.
BTW, my latest thinking is that the M1 Extended Performance line of Mobil 1 oils might be very well suited to gently cleaning out a neglected engine - although this oil is designed for long drain intervals, the extra detergents will probably also help clean a mid-life engine (for a really old engine you probably need a Bilstein flush or something).
High
sorry if this has been discussed before in earlier posts...
thanks in advance.
To your questions of "Do I need to do anything to the engine before I switch to synthetic ? Do you guys think synthetic will increase the life on the engine at this point. "
1. NO. BUT ...Whether you realize this or not; this issue points out the disengenuousness of folks that advocate conventional oil being perfectly ok with 3/5k intervals. Some of the more knowledgeable and coincidently the more fearful would advocate running a innard cleaner such as auto RX and or LC 20 . Why? To get rid of the potential sludge they say will not form using conventional oil with 3/5k intervals !!!
(It is sort of like that Mel Brooks movie joke, where he claims to NOT believe in a god but you see him praying to all of em. When ask why well I dont believe, but you never know where you will end up.
Synthetic will not put back what has already worn down.
Is it a magic elixer? NO!
If you have been using a high quality dino oil with short oil change intervals, the switch is easy. If you have been using a dino oil with fewer detergents, or been stretching your oil changes before now (doesn't sound like the case with you), your first oil change or two after moving to a high quality synthetic might come out a little darker colored - this isn't due to the synthetic component of the new oil affecting your engine, it's due to a better detergent pack (everything tends to get upgraded with premium oils, which synthetics are) in the new oil cleaning out a little "sludge."
"High mileage" formulation dino oils also have extra detergents, and are priced slightly higher than run of the mill dino oils. But they aren't as "shear stable" as full synthetics, which are better for extended (greater than 3,000 mile) oil change intervals.
In some tests I saw, dino oils had sheared down from 30 wt. to 20 wt. oils by 3,000 miles. Mobil 1 5-30 has "engineered" molecules of pretty uniform size, there isn't a lot of "viscoscity enchancer" to shear down in that formula, thus is is great for longer oil change intervals. It is what I use myself.
I "just did it" on a 2004 Honda after the 1st 10k mile OCI with oem conventional oil fill. Most of the purist's would probably have a fit to know: 1 I did a 10,000 mile OCI (with CONVENTIONAL, NO LESS) and when I went to the Mobil One 0w20, I did NOT change the oil filter!! I did go another 10,000 miles on the Mobil One 0w20 (and oem installed oil filter) and at 20k did change the oil AND OIL FILTER, as per Honda owners' manual, owners web site and Honda technical (shop) manual/data.
In your case, procedurally the best is to take off your valve cover (go deeper if you are so inclined) and do a visual inspection. Decide from there. Chances are it is clean as a whistle. If not, do the Auto RX or LP 20 gig per their instructions. As you probably are aware, for more sludged engines most dealers offer a Bosch (hot and pressure chemical) cleaning procedure at 100 on up.
If you are at all fearful, and either cant or do not want to pull off the valve cover; the AUTO RX and or LC-20 are viable way to go, but require multiple oil changes.
Your car may specify 5-20 weight oil. Before you change viscoscity, I recommend that you make sure you don't have a warranty issue with any extended warranty.
That having been said, other than a miniscule difference in fuel economy on a fleetwide basis, 5-20 and 5-30 work virtually the same; I prefer 5-30 in my CR-V. So I am going to recommend 5-30 for longterm use once you have done a little clean up on your engine. (Both viscoscity ranges work fine in midwest winter temperatures.)
Although Mobil 1 is my choice for new cars and will be the one I recommend for your long term use, since your car is is higher mileage vehicle, it could probably use a "clean up" cycle of two strongly detergent oil changes.
My preferred style of cleanup is to use a high detergent oil which can hold a lot of contaminants; fortunately enough, there is a whole line of oils purpose built with dirt in mind, and those are the "CF" etc. diesel rated oils. Shell Rotella T 5-40 is such an oil, it is fully synthetic to boot, and it is cheap at Walmart.
A side bar: very few passenger car oils can be used in light duty (pickup truck and suv) diesel use, but many light diesel application oils can be used in passenger cars - look for the SAE rating on the bottle and it will tell you the applications - you need an SL grade oil (the new SM grade cuts back so heavily on antiwear additives that I don't know of any that also qualify for diesel use). (The old Mobil dino "Clean One" passenger car oils also had a light diesel rating.)
Anyway, a cheaper alternative to Mobil 1 for your cleanup phase is the Shell Rotella T Full Synthetic 5W-40, which is available in 4 quart jugs for about $12 from Walmart. Although it is a little thicker than 5-30, it is well within the range of oils that your car can take, according to the forum at the www.rotella.com website. (But you should return to 5-30 or 5-20 after the cleaning phase to save on gas mileage.)
Rotella 5-40 is a full synthetic Group III oil, which is the cheap alternative to Group IV (Mobil 1) full synthetics; whereas Group IV takes gases and engineers "oil" molecules out of the gas, Group III's take dino oil and totally re-engineers (not merely refines) them into uniform molecules free from wax and other contaminants. Group III oils are shear stable and more thermal resistant, although Group IV beats them.
Anyway, use any filter you want (although most of us hate Fram!), take in the Rotella jug, and get an oil change. Your car will immediately be better protected, no matter how you drive, by the robust full synthetic base stock, while your engine will be cleaned up a great deal by the high diesel-spec detergent levels.
I would keep this oil in for 2,500 miles, checking the dipstick at every other gas fillup to monitor any change in oil color, then do a second Rotella T oil and filter change after 2,500 miles. The filter should have trapped a lot of particulate sludge. Then go another 2,500 miles, switch to Mobil 1 5-30 (cheaper and easier to find) or 5-20. I would use not more than 5,000 mile oil changes, even with a full synthetic, since although the oil lasts, the additive pack gets worn down at the same rate as regular dino oil (maybe it is a little better additive pack, but why push it?). If you want longer oil changes, conside the new Mobil 1 Extended Protection variants of Mobil 1, which have extra additives.
Finally, also keep in mind your purchaser will be happier with receipts showing 5,000 mile oil changes, than receipts showing longer intervals, no matter what kind of oil you put in your car.
On oil filters and Auto RX: a lot of oil heads (including me) like the Champion brand of filters sold under the STP brand at Autozone, or very cheaply as the Supertech brand at Walmart. The Purolator Pure One filter is supposed to filter out smaller particles than its competitors but doesn't seem as popular. Fram's have be cut apart and many complained about certain flimsy/cheap design aspects. I don't recommend Auto RX for the simple reason that it is derived from a printing press lubricant, not a gasoline or diesel engine lubricant, and its inventor doesn't have the resources or test equipment to put it through standard engine oil tests. It seems to have worked fine for a lot of users, but I wouldn't take a chance.
Finally, if you are "tuning up" your car, try running a few tanks of Chevron, Union 76, or Shell gas through it, read about the extra detergents in these gasolines at www.toptiergas.com
"The best you can do for an engine is to get it to operating temp ASAP and run it a min of 1 hour at operating temp. Longer is better like say 12 hours. If one drives like the proverbial old man/lady, short trips of 1-6 mins many starts and shut offs, you can expect over the long term to have some ... issues."
I'm writing in reference to one of my kids (21 year old college student), who drives less than 5,000/year, mostly short trips because that's what her transportation needs happen to be. It wouldn't be practical for her to drive unneeded distances to get her engine fully warmed up, even though some of us who participate in these forums might consider doing this, or, at a minimum, feel conflicted by the tradeoff associated with wasting fuel and time versus extending engine life. Does anyone here identify with this dilemma?
The car in question here is a previously owned '02 VW Jetta, 2.0 engine, with 39,000 miles. The first owner used conventional oil, changed the oil only once during the first 25,000 miles, then every 4,000-5,000 miles. My daughter is a careful driver, who will maintain the car better than its first owner. Her intention is to keep this car for many years, if possible.
Questions (Ruking or others):
1. Assuming the oil on this recently purchased Jetta is switched to Mobil 1, what would be your OCI recommendation be? Would the time factor enter into your answer, or just mileage, or some combination of mileage and time?
2. Would you recommend using 5W-30, 10W-30, or some other Mobil 1 for this car? OR, given the type of driving, would you recommend staying with conventional oil and more frequent OCIs? I suspect that synthetic is preferable to conventional oils for predominantly short trip usage, but please confirm.
Thanks.
..." For seasonal viscosity application Owner's Manual.
The following terms must appear on the oil container singly or in combination with other designations:
VW 502 00 or VW500 00 or VW501 01
ACEA A2 or ACEA A3
API-SJ or API-SL "...
I would probably go to a Mobil One 0w40, (if the owners manual corresponds.)
https://www.mobiloil.com/USA-English/MotorOil/Oils/Mobil_1_0W-40.aspx
I would also do a 5000 to 10,000 OCI. If you are at all paranoid about it, 5000 or one year. But if it were me, the 10,000 mile OCI. (in your case 2 years at 5000 per year). The 0w40 is one of Mobil One's best oils, especially for the Euro's.
If I were not using the Delvac One 5w40, aka., Mobil One Truck & SUV 5w40, I'd be using the 0w40.
The Owners Manual recommends using 5W-40 weight oil, but also says that, if this weight isn't available, "you can also use 5W-30", according to the Manual. Recommended OCI is 10,000 miles or 12 months, whichever occurs first. The Owners Manual also says, "under some circumstances the engine oil should be changed more frequently (than 10,000/12 months). Change oil more often if you drive mostly short distances, operate the vehicle in dusty areas or under predominantly stop-and-go traffic conditions, or have your vehicle where temperatures remain below freezing for extended periods." It doesn't say how frequently the oil should be changed under these more severe circumstances, however.
First question: Besides the fact that 5W-30 may yield slightly better fuel economy than 5W-40, what benefit does 5W-40 provide over 5W-30?
Second question: Assuming that Mobil 1 is used, and the driving style described in message #6147, above, would it be advisable to adopt a shorter OCI, such as 5,000 or 6 months, whichever occurs sooner, or is 10,000/12 months okay with Mobil 1?
Third question: which Mobil 1 would be preferable, 5W-30, ZeroW-40, or some other weight?
The reason being, depending on what VW specifications you are speaking the majority of 5w30's do NOT meet the latest VW specifications. If indeed you are speaking of the 2.0 VW (gasser) then stick with the advice of either the 0w40 and/or 5w40.
Also, I'm not cetain what you mean by "backword compatible."
"...the majority of 5w30's do NOT meet the latest VW specifications." Do your comments about 5W-30 apply to Mobil 1 of that viscosity? The primary reason for preferring to use Mobil 1 5W-30 is that it is commonly available at many oil change places. Same goes for Mobil 1 10W-30, whereas some of the other Mobil 1 weights aren't. Since my daughter, who is away at college, doesn't do her own oil changes, easy availability is an important consideration.
Does it matter that the VW Owners Manual doesn't recommend or even mention 0w-40 for the 2.0 gasser? As a side issue I'm thinking that since the car has 39,000 miles on it (that's certainly not old, but not brand new, either), that if the engine has even a minimal leak due to wear, that the 0 viscosity might tend to leave oil puddles.
Finally, what would you recommend for OCIs, given the driving style info in messages #6147 and 6150?
Happy New Year everyone! Your comments have been very informative.
If you are at all paranoid about OCIs do 5k ones. I personaly would do 10k ones.
The VW Owners Manual stipulates API Service SJ for the 2.0 gasser. The info on the Mobil 1 10W-30 that I have in my garage states "API Service SL/CF", and the label goes on to explain that it "exceeds SL, SJ/CF warranty requirements for gasoline and diesel engines.
One more clarification, please, on "I personally would do 10k ones." Even in cases when it takes 2 years or more to put on 10,000 miles?
On a non VW (1996 Toyota Landcruiser I have taken Mobil One 5w30 to three years (5,000 miles per year) to run up to 15,000 miles OCI's.
It just recently went through a 60k mile major tune up at 65,000 miles and the shop had it apart to check the value adjust! It didnt even need an adjustment and they commented that they could see the original factory tooling and the innards were perfectly clean.
Actually this was a no brainer for me. I also have a 10 year old 1994 TLC with 129k miles. It just went through the 120k major tune interval @ 125k . Again, the same thing; spotless innards and valve adjustment not needed. Prior to the tune up it went to a CA "smog only" station with 116k and at that time I felt it needed a tune up badly. However it passed with flying colors and the smog test results were just slightly better than the one taken at the bi annual mark !!! (8 years later!!! ) Both vehicles 94/96 are operated with almost no thought to any of the things we are discussing. (3rd year college and high school (senior) students)
Back on topic for the 2.0, while I am running a 25,000 miles OCI with the TDI (not what I am recommending for your 2.0 VW) with the Mobil One Truck & Suv 5w40, the Mobil One 0w40 is more than up to the task of doing the 10,000 OCI in your 2.0 VW even if it takes 2 years.
On another topic, do you have an opinion on the reliability and durability of the VW 2.0 gasser compared to, say, Honda and Toyota engines of similar displacement (just the engine, since I know Japanese electronics and certain mechanical items are better than the German)?
This spec carries over even to the "low tech," low horsepower 2.0 engine (which is solid and reliable!).
There is a VW webpage (aimed principally at the turbo owners) that lists the oils that satisfy the VW spec.
Valvoline full synthetic 5-40; Pennzoil "European formula" full synthetic 5-40; Quaker State "European formula" full synthetic 5-40; Mobil 1 full synthetic 0-40 (but not Mobil 1 Truck and SUV 5-40!); and Castrol Syntec full synthetic 5-40 (the one most often used at VW dealers) are the common ones I recall from that list.
There are three important factors to the VW spec: (1) viscosity, spec'd at 40 but per VW closer to 35; (2) antiwear additives that might not be permitted under the new American SM (and even the earlier SL) API grades; and (3) upgrades to permit extended oil change intervals. VW doesn't have an oil change monitor light, so 10,000 miles is what they consider an "extended" oil change. If your commute is less than 10 miles you probably fall into the "severe" driving category and even with full synthetic oil would be better off replacing oil every 5,000 miles.
The manual "permits" use of 5-30 where 5-40 (or 0-40) oil is not available, only as a concession to the realities of cheap American oil. Most dealers use Castrol dino oil 5-30 (5-40 is available but costs about $30-40 extra per oil change) and recommend 5,000 mile oil change intervals; not a bad approach, considering the 2.0 has an oil cooler and no known sludge problems, but certainly, imho, a major "downgrade" to the fine engineering for which VW is famous. IMHO, a full synthetic 5-30 is ok to switch for a 5-40 full synthetic; it won't satisfy VW's grade requirement, but it is long life and won't produce sludge. On the other hand, the Mobil 1 5-30 is SM approved and has reduced antiwear additives (to protect cheaper catlytic converters) while the Mobil 1 5-30 EP Extended Performance oil DOESN'T satisfy SM or GF-4 BUT has a better antiwear additive package.
Since I had a 2.0 with stick shift which turned 4,000 at 80 mph, I elected to stick with VW's exact requirements on my second Golf, using nothing but 5-40. I changed oil every 5,000 miles so I'd have optimal protection at all times. Oil changes at VW were about $60, which included the MANDATORY drain plug replacement (not just a washer replacement) and a very high quality VW oil filter. Having lost a drain pan at 43,000 miles on my former VW, I didn't want the same to happen.
I highly recommend VW service over a lube shop. It is worth the minor inconvenience. I'd skip or defer the 20,000 mile "minor maintenance" rather than skipping or extending VW dealer oil changes. On the other hand the 40,000 mile interval "major maintenance" is a must do, because you get new spark plugs and an air filter. I shopped around dealers for my major maintenance, and found prices ranging from $300 to $500, so it pays to shop dealers.
OVERALL, except for the drain pan damaged by an independent lube shop, my maintenance costs on the VW were VERY low - limited to the 5,000 mile oil changes, which cost a little more, but saving a lot on the scheduled maintenance (the VW dealers I used followed the manual requirements exactly, not including all the "extras" found on Japanese and American brand service calls, which really reduced the price of maintenance).
DON'T let a VW service advisor tell you 5-30 dino Castrol is ok. It isn't what's best for your car.
Don't let anyone besides a VW dealer work on your car. They really know what they are doing, and usually do the job right the first time, and don't damage other stuff in the process. (But do competively shop for a great dealer, don't settle for a poor or mediocre one.)
How is the 2.0 "certainly, imho, a major "downgrade" to the fine engineering for which VW is famous?"
The first owner of my daughter's newly purchased '02 Jetta 2.0 used 5W-30 dino from the first oil change until 39,000, the mileage when my daughter bought it. What are the likely consequences of using this oil, which was changed by an independent service station garage?
Thanks in advance.
On GM cars, people have reported up to 10,000 to 12,000 mile indicated oil changes, which is simply amazing since the GM algorithm is based on conventional (dino) oil and not specially formulated extended drain interval full synthetics.
Since VW's don't have an oil change monitor, I think it's better to stick with their maximum 10,000 mile oil changes, and best to "discount" that back to 5,000 miles based on "enthusiast" level driving, plus possible harsh midwest winters, short trips, etc. WITH full synthetic, extended drain interval oil. That's because my predisposition is to baby the engine, whereas I suspect ruking1 has an exuberance for seeing just how good modern full synthetic oils are and hence how long they will last ... same fact base, same analysis, different predispositions. (My personal opinion is that the twin costs of using synthetic oil and changing at 5,000 miles are the least expensive part of total costs of ownership and provide the greatest peace of mind for the dollar spent; even at 5,000 mile changes, the owner is saving vs. the lube shop mentality of 3,000 mile changes.)
Re the owner with 39,000 miles - that isn't too late to upgrade to full synthetic. Odds are - based on the GM feedback - that 10,000 mile oil changes with dino oil probably didn't hurt it much, if any, assuming the next to worse case scenario that the former owner followed the manual and not his or her dealer's or lube shop's advice. But I'd run full synthetic, highly detergent, oil for the next two changes at least with 5,000 mile changes, just to pick up any early sludge and clean it out, even if you thereafter stick with 10,000 mile changes (or one year, whichever comes first, per the manual, I believe). The new Mobil 1 full synthetic Extended Protection version would be ideal due to its extra detergent and superior anti-wear additives, even though you'd have to use 5-30 instead of the technically correct 0 or 5-40 (the original formula is in 0-40, the Extended Protection isn't). The Mobil1.com websit has interesting faqs.
No connection here with VW or its dealers. I favor factory dealers for all makes, so long as you have the will-power to decline the "over" service and just take the factory warranty book service. A lot of Japanese and domestic dealers include a lot of unnecessary (imho) and costly "extras". That's why a service that should cost about $150 ends up costing $500. Lube shops used to be a "less hassle" alternative, but as they add "extras" like coolant and tranny flushes, and even "minor services", the overselling there is as annoying as at the dealer...but without the factory training and manuals.
Just put Mobil-1 in my Sienna, and it was very easy to change (much easier than my Hondas and their hard to reach filters). I was amazed to see that the Sienna actually has a built in plastic funnel below the oil filter to keep the oil from dribbling all over the engine - nice attention to detail.
My 1993 Pathfinder SE had a drain plug for the slushbox as well. Rear disc brakes too. :surprise:
Once in my album, click on "Caravan Stuff" and then click on the last photo DGC3.8-104K.jpg for the detail view of the rocker arm assembly. Interestingly enough, it has been about 4,000 miles since I changed the oil and as can clearly be seen in the small pool of oil in the rocker arm, the oil is still almost as clear as the day I poured it in.
http://photos.yahoo.com/shipo
Best Regards,
Shipo
Shell DOES make a full synthetic (Group III, not IV, though) for diesel application, Rotella 5-40. It is Cummins and other big rig etc. approved and works in light duty diesels too. Walmart carries it.
Any help would be appreciated on this question. Also, will the gas mileage improve at all? I do 90% city driving and usually drive only 24 miles a day.
Thanks all!
The Sandman
Background: I purchased this carefully maintained and driven car from the original owner 1/2 years ago, with 103,000 miles on it. The car had had regular 3000 mile oil changes with dino oil since new. Due to it good condition, and despite its age, I decided to convert it to Mobil 1, because its a keeper. The Mobil web site recommends Mobil 1 10W-40 for this car (it's got the slower revving/higher torque 121 hp 2.7L I-6 ETA engine [4700 rpm redline] rather than the faster revving/lower torque 168 hp I-6 found in the 325i and 325is). While Mobil 1 is my first choice, I haven't been able to find Mobil 1 10W-40 in my area. Therefore, I used Mobil 1 10w-30. I'm afraid to go with 0W-40 because the engine leaks a few drops of oil while parked overnight. I can live with the current amount of leaking, but probably not with the increased leaking of 0W-40. Mobil dino 10W-40 is available in my area, but I would prefer to stay with synthetic.
Question: What brands of synthetic 10W-40 would you consider to be good alternatives to Mobil 1, and, just as importantly, which ones, if any, would you recommend not using? Or would you just stay with Mobil 1 10W-30, even though 40 weight is common for BMWs? I live in Maryland, with year round temperatures typically ranging from 25 - 95 degrees F.
Thanks in advance for your suggestions.
It might be a very common thing specific to that particular model year and any/or combo. I would not have an issue with the 0w40. I would also be tempted to look at the 5w40 if either of them give you any issues.
Shifty, I assumed that the "0"W would mean that any leakage, when the car is parked in the garage or driveway, would be greater than with, say, "10"W, but I interpret your response to mean that it doesn't matter. That surprises me, as it's contrary to what I thought. I knew that the second number is more significant than the first, but I thought that when the engine is shut down the first number would affect leakage. Since the amount of oil loss is low, I'm more concerned by oil spots on the garage floor than by losses while driving.
I was hoping that one or both of you would suggest good alternative brands to Mobil 1.
I am now using Mobil 1 10W-30 because I felt it was a reasonable substitute for 10W-40, but I'm not really comfortable with this because it's not what's recommended. I imagine that it makes virtually no difference whether I use 10W-30 or 10W-40 for a mix of local plus some highway driving, but I'm thinking of taking a cross country trip this summer with this car. This would mean hour after hour of high speed driving. Please correct me if I'm wrong, but isn't this type of driving, particularly in hot weather, where "40" would provide better protection than "30"?
As a side note, I would avoid using aftermarket oil filters. Even if you change your own oil, I would purchase the OEM filters either online or at the dealer. The OEM filters were designed for your specific engine, and is an integral part of maintaining the correct oil pressure during the engine's operation...
Hope this helps...
for the length of time most of us keep cars, and for the way most of us use them, I think all this is just splitting hairs.
But you are correct in that 10W40 is better in hot climates - summertime.
The 40 viscosity is what makes it more suitable.
Your car is an older model that was apparently spec'd to use conventional motor oil with high levels of detergent additives and antiwear additives. It also apparently wants a thicker viscoscity (40) than normal these days (30, at least in America; in Europe the standard for luxury and performance cars has shifted to 5-40 or 0-40, full synthetic so it will stand up to the extended viscosity range).
Rotella T 5-40 is a "throwback" oil - it emphasizes robust engine protection ("robust" is a word you see often on the Rotella.com website) but fails to meet the ILSAC "starburst" requirements for high levels of friction modifiers (for better mileage) and lower levels of phosphorous and zinc (for longer catalytic converter life). For the same reasons it is an SL oil, the last generation rating, instead of an SM oil, the current SAE rating.
Keep in mind that over the past couple of decades, oils tended only to get better. In fact, the SL and SM requirements pretty much dictate the use of hydrocracked (using catalysts) oil instead of 19th century "solvent refined" base oil. That's good. But, the bad part, is that engine protection, in the minds of a lot of people, is starting to get sacrifice to increase gas mileage and protect catalytic converters. There was an element of this when the SL standard was introduced, and more of it when the SM standard was introduced - so much so that one great standby, Mobil 1, has developed a split personality - the "regular" line of full synthetic, with SM and Starburst compliance, and an "Extended Performance" line with no SM and no Starburst compliance. Wow!
The Mobil 1 Extended Performance line is probably the best protection money can buy right now, at the risk of being "out of compliance" with some 2006 owner's manuals which require SM and Starburst compliance (so the government will "honor" their fuel economy studies).
But, at a much lower price, you can get Rotella 5-40 (Walmart, $14 a gallon jug). And, since your car is ok for 40, you'll be fine on viscosity...and of course Rotella is backwards compatible and satisfies the SAE requirements in effect when your car was made (you should check the manual, though, to see if BMW had any additional specification requirements - Mobil 1 0-40 satisfies all BMW requirements, past and present).
Rotella T is one of the "new synthetics." It starts from crude oil, and is hydrocracked/isomerized to the point where it is Group III (possibly Group III+) which means (i) is has little wax in it, which is why it flows like a 5W oil when it is cold; and (ii) it is very "shear stable," since its molecules have been "engineered" to the point where the intrinsic viscoscity index is very high (Mobil 1 uses gases as its starting point - it has no relation to crude oil - and has even greater viscoscity, to the point where I understand no visoscity index improvers are required at all in its 5-30 grade). This means Rotella won't break down from 5-40 to 5-30 or worse during your oil change interval.
Although Rotella is full synthetic, given its approximately $3.50 per quart price when you buy it by the jug (the only way I've seen it at Walmart), it would probably be a good idea to stick with 3,000 mile oil changes to see how much dirt and sludge comes out of your crankcase during oil changes. You might consider Walmart for your oil changes, since I have seen some fairly high end cars in their bays from time to time, as well as the more expected "beaters." It is probably worthwhile to buy a new drain plug and a few washers (if they are two piece assemblies; my VW was one piece) since at the mileage you report, the drain plug could be beat up.
You might also consider trying to track down a Futamoto or Fram drain plug, which would allow future oil drains without actually removing the plug; this would help if the threads on your oil pan have been abused over the years. Oil pans are expensive, and if the threads in yours are near the end of their life, I'd probably get a Futamoto (if there is an applicatin) and Loctite it in....