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 > Technical Articles: / BMW E36 3-Series (1992-1999) >
More than You Ever Wanted to Know About Motor Oil

Pelican Technical Article:

More than You Ever Wanted to Know About Motor Oil

Ed Hackett


1 hour1 hr






Your brain and some reading glasses (if needed)

Applicable Models:

BMW E30 3-Series (1984-93)
BMW E36 3-Series (1992-99)
BMW E46 3-Series (1999-06)

Parts Required:

Oil for your BMW

Performance Gain:

Use the best oil for your BMW

Complementary Modification:

Perform an oil and filter change on your BMW
101 Performance Projects for Your BMW 3 Series

This article is one in a series that have been released in conjunction with Wayne's new book, 101 Performance Projects for Your BMW 3 Series. The book contains 272 pages of full color projects detailing everything from performance mods to timing the camshafts. With more than 650+ full-color glossy photos accompanying extensive step-by-step procedures, this book is required reading in any 3 Series owner's collection. The book was released in August 2006, and is available for ordering now. See The Official Book Website for more details.

Choosing the best motor oil is a topic that comes up frequently in discussions between motoheads, whether they are talking about motorcycles or cars. The following article is intended to help you make a choice based on more than the advertising hype.

Oil companies provide data on their oils most often referred to as "typical inspection data". This is an average of the actual physical and a few common chemical properties of their oils. This information is available to the public through their distributors or by writing or calling the company directly. I have compiled a list of the most popular, premium oils so that a ready comparison can be made. If your favorite oil is not on the list get the data from the distributor and use what I have as a data base.
This article is going to look at six of the most important properties of a motor oil readily available to the public: viscosity, viscosity index (VI), flash point, pour point, % sulfated ash, and % zinc.
Viscosity is a measure of the "flowability" of an oil. More specifically, it is the property of an oil to develop and maintain a certain amount of shearing stress dependent on flow, and then to offer continued resistance to flow. Thicker oils generally have a higher viscosity, and thinner oils a lower viscosity. This is the most important property for an engine. An oil with too low a viscosity can shear and loose film strength at high temperatures. An oil with too high a viscosity may not pump to the proper parts at low temperatures and the film may tear at high rpm.

The weights given on oils are arbitrary numbers assigned by the S.A.E. (Society of Automotive Engineers). These numbers correspond to "real" viscosity, as measured by several accepted techniques. These measurements are taken at specific temperatures. Oils that fall into a certain range are designated 5, 10, 20, 30, 40, 50 by the S.A.E. The W means the oil meets specifications for viscosity at 0 F and is therefore suitable for Winter use.

The following chart shows the relationship of "real" viscosity to their S.A.E. assigned numbers. The relationship of gear oils to engine oils is also shown.
| |
| SAE Gear Viscosity Number |
| ________________________________________________________ |
| |75W |80W |85W| 90 | 140 | |
| |____|_____|___|______________|________________________| |
| |
| SAE Crank Case Viscosity Number |
| ____________________________ |
| |10| 20 | 30 | 40 | 50 | |
| |__|_____|____|_____|______| |
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
viscosity cSt @ 100 degrees C

Multi viscosity oils work like this: Polymers are added to a light base (5W, 10W, 20W), which prevent the oil from thinning as much as it warms up. At cold temperatures the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.

Multi viscosity oils are one of the great improvements in oils, but they should be chosen wisely. Always use a multi grade with the narrowest span of viscosity that is appropriate for the temperatures you are going to encounter. In the winter base your decision on the lowest temperature you will encounter, in the summer, the highest temperature you expect. The polymers can shear and burn forming deposits that can cause ring sticking and other problems. 10W-40 and 5W-30 require a lot of polymers (synthetics excluded) to achieve that range. This has caused problems in diesel engines, but fewer polymers are better for all engines. The wide viscosity range oils, in general, are more prone to viscosity and thermal breakdown due to the high polymer content. It is the oil that lubricates, not the additives. Oils that can do their job with the fewest additives are the best.

Very few manufactures recommend 10W-40 any more, and some threaten to void warranties if it is used. It was not included in this article for that reason. 20W-50 is the same 30 point spread, but because it starts with a heavier base it requires less viscosity index improvers (polymers) to do the job. AMSOIL can formulate their 10W-30 and 15W-40 with no viscosity index improvers but uses some in the 10W-40 and 5W-30. Mobil 1 uses no viscosity improvers in their 5W-30, and I assume the new 10W-30. Follow your manufacturer's recommendations as to which weights are appropriate for your vehicle.

Viscosity Index is an empirical number indicating the rate of change in viscosity of an oil within a given temperature range. Higher numbers indicate a low change, lower numbers indicate a relatively large change. The higher the number the better. This is one major property of an oil that keeps your bearings happy. These numbers can only be compared within a viscosity range. It is not an indication of how well the oil resists thermal breakdown.

Flash point is the temperature at which an oil gives off vapors that can be ignited with a flame held over the oil. The lower the flash point the greater tendency for the oil to suffer vaporization loss at high temperatures and to burn off on hot cylinder walls and pistons. The flash point can be an indicator of the quality of the base stock used. The higher the flash point the better. 400 F is the minimum to prevent possible high consumption. Flash point is in degrees F.

Pour point is 5 degrees F above the point at which a chilled oil shows no movement at the surface for 5 seconds when inclined. This measurement is especially important for oils used in the winter. A borderline pumping temperature is given by some manufacturers. This is the temperature at which the oil will pump and maintain adequate oil pressure. This was not given by a lot of the manufacturers, but seems to be about 20 degrees F above the pour point. The lower the pour point the better. Pour point is in degrees F.

% sulfated ash is how much solid material is left when the oil burns. A high ash content will tend to form more sludge and deposits in the engine. Low ash content also seems to promote long valve life. Look for oils with a low ash content.

% zinc is the amount of zinc used as an extreme pressure, anti- wear additive. The zinc is only used when there is actual metal to metal contact in the engine. Hopefully the oil will do its job and this will rarely occur, but if it does, the zinc compounds react with the metal to prevent scuffing and wear. A level of .11% is enough to protect an automobile engine for the extended oil drain interval, under normal use. Those of you with high revving, air cooled motorcycles or turbo charged cars or bikes might want to look at the oils with the higher zinc content. More doesn't give you better protection, it gives you longer protection if the rate of metal to metal contact is abnormally high. High zinc content can lead to deposit formation and plug fouling.

The Data: Listed alphabetically --- indicates the data was not available

Brand VI Flash Pour %ash %zinc
Amsoil 136 482 -38 <.5 ---
Castrol GTX 122 440 -15 .85 .12
Exxon High Performance 119 419 -13 .70 .11
Havoline Formula 3 125 465 -30 1.0 ---
Kendall GT-1 129 390 -25 1.0 .16
Pennzoil GT Perf. 120 460 -10 .9 ---
Quaker State Dlx. 155 430 -25 .9 ---
Red Line 150 503 -49 --- ---
Shell Truck Guard 130 450 -15 1.0 .15
Spectro Golden 4 174 440 -35 --- 1.5
Spectro Golden M.G. 174 440 -35 --- .13
Unocal 121 432 -11 .74 .12
Valvoline All Climate 125 430 -10 1.0 .11
Valvoline Turbo 140 440 -10 .99 .13
Valvoline Race 140 425 -10 1.2 .20
Valvoline Synthetic 146 465 -40 <1.5 .12
Castrol Multi-Grade 110 440 -15 .85 .12
Quaker State 121 415 -15 .9 ---
Chevron 204 415 -18 .96 .11
Mobil 1 170 470 -55 --- ---
Mystic JT8 144 420 -20 1.7 .15
Red Line 152 503 -49 --- ---
Castrol Syntec 180 437 -45 1.2 .10    - .095 % Phosphor
Quaker State Synquest 173 457 -76 --- ---
Pennzoil Performax 176 --- -69 --- ---
Havoline 170 450 -40 1.4 ---
AMSOIL 135 460 -38 <.5 ---
Castrol 134 415 -15 1.3 .14
Chevron Delo 400 136 421 -27 1.0 ---
Exxon XD3 --- 417 -11.9 .9 .14
Exxon XD3 Extra 135 399 -11 .95 .13
Kendall GT-1 135 410 -25 1.0 .16
Mystic JT8 142 440 -20 1.7 .15
Red Line 149 495 -40 --- ---
Shell Rotella w/XLA 146 410 -25 1.0 .13
Valvoline All Fleet 140 --- -10 1.0 .15
Valvoline Turbo 140 420 -10 .99 .13
AMSOIL 142 480 -70 <.5 ---
Castrol GTX 140 415 -33 .85 .12
Chevron Supreme 150 401 -26 .96 .11
Exxon Superflo Hi Perf 135 392 -22 .70 .11
Exxon Superflo Supreme 133 400 -31 .85 .13
Havoline Formula 3 139 430 -30 1.0 ---
Kendall GT-1 139 390 -25 1.0 .16
Mobil 1 160 450 -65 --- ---
Pennzoil PLZ Turbo 140 410 -27 1.0 ---
Quaker State 156 410 -30 .9 ---
Red Line 139 475 -40 --- ---
Shell Fire and Ice 155 410 -35 .9 .12
Shell Super 2000 155 410 -35 1.0 .13
Shell Truck Guard 155 405 -35 1.0 .15
Spectro Golden M.G. 175 405 -40 --- ---
Unocal Super 153 428 -33 .92 .12
Valvoline All Climate 130 410 -26 1.0 .11
Valvoline Turbo 135 410 -26 .99 .13
Valvoline Race 130 410 -26 1.2 .20
Valvoline Synthetic 140 450 -40 <1.5 .12
AMSOIL 168 480 -76 <.5 ---
Castrol GTX 156 400 -35 .80 .12
Chevron Supreme 202? 354 -46 .96 .11
Chevron Supreme Synt. 165 446 -72 1.1 .12
Exxon Superflow HP 148 392 -22 .70 .11
Havoline Formula 3 158 420 -40 1.0 ---
Mobil 1 165 445 -65 --- ---
Mystic JT8 161 390 -25 .95 .1
Quaker State 165 405 -35 .9 ---
Red Line 151 455 -49 --- ---
Shell Fire and Ice 167 405 -35 .9 .12
Unocal 151 414 -33 .81 .12
Valvoline All Climate 135 405 -40 1.0 .11
Valvoline Turbo 158 405 -40 .99 .13
Valvoline Synthetic 160 435 -40 <1.5 .12

All of the oils above meet current SG/CD ratings and all vehicle manufacture's warranty requirements in the proper viscosity. All are "good enough", but those with the better numbers are icing on the cake.

The synthetics offer the only truly significant differences, due to their superior high temperature oxidation resistance, high film strength, very low tendency to form deposits, stable viscosity base, and low temperature flow characteristics. Synthetics are superior lubricants compared to traditional petroleum oils. You will have to decide if their high cost is justified in your application.

The extended oil drain intervals given by the vehicle manufacturers (typically 7500 miles) and synthetic oil companies (up to 25,000 miles) are for what is called normal service. Normal service is defined as the engine at normal operating temperature, at highway speeds, and in a dust free environment. Stop and go, city driving, trips of less than 10 miles, or extreme heat or cold puts the oil change interval into the severe service category, which is 3000 miles for most vehicles. Synthetics can be run two to three times the mileage of petroleum oils with no problems. They do not react to combustion and combustion by-products to the extent that the dead dinosaur juice does. The longer drain intervals possible help take the bite out of the higher cost of the synthetics. If your car or bike is still under warranty you will have to stick to the recommended drain intervals. These are set for petroleum oils and the manufacturers make no official allowance for the use of synthetics.

Oil additives should not be used. The oil companies have gone to great lengths to develop an additive package that meets the vehicle's requirements. Some of these additives are synergistic, that is the effect of two additives together is greater than the effect of each acting separately. If you add anything to the oil you may upset this balance and prevent the oil from performing to specification.

The numbers above are not, by any means, all there is to determining what makes a top quality oil. The exact base stock used, the type, quality, and quantity of additives used are very important. The given data combined with the manufacturer's claims, your personal experience, and the reputation of the oil among others who use it should help you make an informed choice.

Comments and Suggestions:
Phil Comments: Based on the statement "All of the oils above meet current SG/CD ratings" this article appears to be quite old. Current ratings as of 2016 are SN/CJ-4. Do you know how current the numbers are in the "data" section? Have they been updated since the article was first written?
June 28, 2016
  Followup from the Pelican Staff: This article was written for E36 models, so it would not be current when it comes to modern BMW engine. I will see if we can have it updated asap. - Nick at Pelican Parts  
ricky bobby Comments: I got a 95 325is e36 m50b25 vanos, currently used at the track as a drift car. What is the best oil for hard driving at the track and "daily use" ? Im thinking 15w50 full syntheticmobil one but not sure.
May 17, 2016
  Followup from the Pelican Staff: 10/30 synthetic on that model. But double check your owner's manual. - Nick at Pelican Parts  
Fignite Comments: Hi,
I recently bought a '98 Z3 1.9. The dealer said that they had changed the oil but I do not know the grade what type or grade. Could you tell me whether synthetic oils be mixed with non synthetic oils and vice a versa? Thank you.
April 14, 2016
  Followup from the Pelican Staff: Yes, they can be mixed. When replacing, try to use one type of oil. If topping up, it is Ok to mix for a temporary solution. - Nick at Pelican Parts  
Physixe Comments: I have a 320D touring from 2001 i drive around 300km on highway everyday ...i live in Denmark Scandinavia..
wh at oil for winter......and what oil type for sommer ..
March 12, 2016
  Followup from the Pelican Staff: I am not familiar with the European spec engine in your vehicle. I would go with what is says in your owner's manual. - Nick at Pelican Parts  
Jon Comments: Hi there, thanks for all the help & advice! I have a 1991 318is with over 220K, haven't seen the M42 mentioned here so wanted to ask; Have been running BMW synthetic 5w30 since I've owned it the past five years/50k miles, but am now in Oregon and considering either switching to non-synthetic or going back to stock viscosity. Any thoughts? Also running new stock tranny/diff fluids every 2 yrs. No issues. Thanks!
January 31, 2016
  Followup from the Pelican Staff: You can switch back and forth. It;s up to you. However, when an engine is older, it needs better care. - Nick at Pelican Parts  
Chris Perez Comments: I just got a 03 325ci,m54 engine, I'm new to the bmw world. I live in las vegas, NV it's hot in summer cold in winter. What's the best oil I can use in my car?
January 24, 2016
  Followup from the Pelican Staff: 5w30 I would think. BMW synthetic. Check your owner's manual to be sure. - Nick at Pelican Parts  
Junior Comments: I have a 96' 328i Cabrio with 198k not sure what oil to use its hot where i live in the inland empire.What kind of oil would you recommend? thanks
July 24, 2015
  Followup from the Pelican Staff: 5w/30. To be sure, check your owner's manual. - Nick at Pelican Parts  
Benny Comments: I own a 1995 325is its a street car but I drive it pretty hard most of the time, I'm considering getting Royal Purple synthetic oil and wanted to know if 20w-50 is a good choice or is it too thick? I want a year round oil.
January 3, 2015
  Followup from the Pelican Staff: I'd say go for the 10/30. - Nick at Pelican Parts  
Dylan Comments: I have a 95 M3 and run mobil 1 5w-30 I am currently live in Wisconsin and it is starting to get cold is this oil ok to use? I feel like i am hearing lifter tick but may be wrong. also after and oil change and adding 7.3 quarts of oil my dip stick still reads low, any suggestions?
December 9, 2014
  Followup from the Pelican Staff: You should be OK. However, to be sure check your owner's manual. - Nick at Pelican Parts  
mel279 Comments: Hi...I.would like to know which grade of oil would be suitable for my e46 320d 2002 model and we have only hot climate.
May 10, 2014
  Followup from the Pelican Staff: We don't have you engine here in the US. SO I don't have any experience replacing the oil. Give our parts specialists a call at 1-888-280-7799. They can help you find the right part.
- Nick at Pelican Parts
Speedy Comments: I have a 1995 740il with 139,000 miles on it. What type of oil and what grade do you recommend I use. I live in the south east with mild winters.
June 17, 2013
  Followup from the Pelican Staff: I always go with what BMW recommends. This will be listed in your owners manual. Give our parts specialists a call at 1-888-280-7799. They can help you find the right oil. - Nick at Pelican Parts  
bill Comments: Is slick 50 bad to use? Does it work?
August 29, 2012
  Followup from the Pelican Staff: I don't use it. I cannot offer any feedback on it. i would stick to oils that are approved by BMW. - Nick at Pelican Parts  
anthony4nj Comments: Hi
I hav 101 projects boxster In Oct of 2011 I purschase my first 1998 Boxster with 47k. I haded Porsche change the oilnever again and a full brake job pads and rotorsthrough a friend..The dealer mentioned to me that it was a little wet around a few areas but no leaks that he can see he stated not to worry just drive it and have fun ..So the next day I put cardbord underneath the car and let it sit a few days came back to it to see No Spots..?
Now my question..
Should I use reg motor oil or continue to use synthetic. You did mentioned in your book that it would be better with reg oil..If that is correct which oil would be right and correct weight ..I do live in NJ

Thank you for your responce

January 28, 2012
  Followup from the Pelican Staff: Check your owner's manual for the oil Porsche recommends. Personally Ilike synnthetic, but it has to meet the ratings set by Porsche. - Nick at Pelican Parts  
Brandon Comments: i recently got a 84 318i with 305,000kms 5spd i live in canada what oil do you recomend?
December 21, 2011
  Followup from the Pelican Staff: I would use an oil that is approved by BMW. Check your owner's manual. You will have to choose the SAE rating depending on your climate.- Nick at Pelican Parts  
Scott Comments: ... This is by far the best write up for an easy lesson in oil on the web yet!
- I have a E36 328i '99.. 160k - Live in UK where outside temps range from below freezing in winter to around 28C in summer. For last 35k I've used 5w30 fully synth Castrol/Mobil 1... However, BMW recommend 10w40 part synth. I drive it hard despite the higher mileage.....
Am I winning or losing??
September 11, 2011
  Followup from the Pelican Staff: You're fine. A full synthetic is a great oil. Just use an oil approved by BMW. - Nick at Pelican Parts  
Gee Comments: Hi I have recently purchased a 1997 528i with 157,000 iles on it the owner used Valvoline 20W50 , I want to change to Royal Purple 20W50 we live in Georgia where the summer gets pretty hot , is this okay for the mileage it has ?
June 12, 2011
  Followup from the Pelican Staff: Sure. you should be OK. 20w50 is a good hot climate oil. - Nick at Pelican Parts  
jesu Comments: So it seems like Mobil 1 synthetic, RedLine and Amsoil are the best choices to avoid sludge, I still got to add a qt every 2500 miles. i was gonna switch to Castrol Synth. but wait a minute; I want my valves to last longer. I'm sticking to LubroMoly while i can afford it.
May 22, 2011
  Followup from the Pelican Staff: Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
Josh C Comments: Hey Wayne
I currently run the Lubra Moly 5W-40 year round , i do how ever have a nice constant tick going on. the car is a 1995 540ia with about 130k on motor M60B40 alusil. The car runs year round also so i am wondering if the oil should be changed to another weight or is all good to go? I do drive spirited i get a chance.
May 15, 2011
  Followup from the Pelican Staff: Where is the tick coming from? Could it be a lifter noise? I always suggest using an oil approved by BMW. If you are, don't sweat it as long as the SAE rating is good for your climate. - Nick at Pelican Parts  
Kamal Comments: I have the EUR M3 3.2L and use the castrol edge sport 10w60, what do you recomend, live in hot city
May 14, 2011
  Followup from the Pelican Staff: Here are the specs for US M engines:

The following is the only recommended and approved synthetic oil for BMW M (Motorsport) vehicles in the US market with gasoline engines, at the present time.
BMW Long-life rating LL-01 Synthetic Oils for BMW M vehicles equipped with S54, S62, S65 or S85 engines
Castrol EDGE Professional TWS Motorsport SAE 10W-60 Synthetic Engine Oil
BMW part number 07 51 0 009 420
Castrol EDGE Professional OE 5W30 Synthetic Engine Oil
BMW part number 07 51 0 037 195 - Nick at Pelican Parts
Pogue Comments: I use mobile 1 full synthetic 10w-40 in my 1997 E36 328i in San Diego Ca. Is this wrong?
January 29, 2011
  Followup from the Pelican Staff: Nope, that should work fine for you. In our very mild climate, nearly any weight / brand of oil will work perfectly fine. It's always pretty warm around here, and never too hot. - Wayne at Pelican Parts  
John Comments: Wayne,,thanks,,,,would you say that amount of consumption is normal for an engine that age,,and what would suggest i use in the summer months..
December 1, 2010
  Followup from the Pelican Staff: Sounds a little higher than I would normally like to see, but perfectly typical for a high mileage engine like yours. - Wayne at Pelican Parts  
John Comments: There in no info here on the Mobil1 0w40 European blend whic i have been using year round in my 97 328i sedan,,with 145,000 miles,,seems to run great,,engine is very quiet,,and it only uses about a quart every 2,100 miles,,,i use it year round,,should i change anything....

forgot to say i am in Ohio
November 30, 2010
  Followup from the Pelican Staff: Mobil 0-40 is what I use in my race engines. Typically for street cars, I like to run a little thicker oil in the summer, as it helps to keep temperatures down. - Wayne at Pelican Parts  
Robert Comments: I have a 1997 M3, what type of oil should I be using? Currentl I use full synthetic 10w-30.
October 22, 2010
  Followup from the Pelican Staff: That weight works perfectly fine. I like to use heavier weight oils in the summer, and lighter weight in the winter. - Wayne at Pelican Parts  
Martin Comments: I have a 1987 325is 5spd with more than 217,000 miles on it and I drive it pretty hard. I'm currently using mobil 1 15w50 syntheic oil. My car has a noticably loud ticking noise thats coming from the cylinder head even after the valves were adjust and the head was rebuilt and shaved. What kind of oil would you recommend for my car? I live in Los angeles by the way.
September 21, 2010
  Followup from the Pelican Staff: You might want to switch to a little thicker oil for Los Angeles driving. Your car doesn't have hydraulic lifters, so I suspect one of the valve lash adjusters is loose, or one of the valve adjustments are off. - Wayne at Pelican Parts  
Matt Comments: In this article a 10W-40 is recommended in colder climates but above you say that 10W-40 is no longer recommended by manufacturers. I have been using Castol high mileage 10W-40 in my 98' 323i that just passed the 189,000 mi I in trouble?
July 7, 2010
  Followup from the Pelican Staff: The weight of the oil is less important than the frequency of oil changes. The Castrol oil you're using should be perfect for your car. - Wayne at Pelican Parts  
design2doc Comments: Thank you Wayne for your much needed suggestions on my 1994, 525i.My big brother bled my cooling system and the coolant level light indicator went off and the heat blows hot,now the car idles kinda ruff and when I start the engine the oil light comes on briefly the oil level was fine upon checking it with the car warmed up to normal operating temp? any suggestions
June 21, 2010
  Followup from the Pelican Staff: You probably have a vacuum leak that is causing the engine to run rough. Check to see what codes, if any, the computer is outputting as errors? - Wayne at Pelican Parts  
Garfield Comments: I just purchased a 93 525i with 175,000. The manual say to use to use 15w40 for oil the oils change. My peers say to use 10w30 or straight synthetic. Im confused and but dont want to hurt the engine. I am a new BMW owner
April 22, 2010
  Followup from the Pelican Staff: 10w30 works for where I live. I always suggest using an oil approved by BMW. If you are, don't sweat it as long as the SAE rating is good for your climate. - Nick at Pelican Parts  
Trevor Comments: I have been using 20W-50 Royal Purple XPR Racing Oil in my '91 535i. Should I switch to a 15w-40 for winter, or go even lighter? I will say, the engine is a heck of a lot smoother with the Royal Purple. Oh and is it cool to change at 5000, or 7500? I have been religious about changing at 3000 even with the expensive stuff, but I do run it pretty hard.
August 25, 2009
  Followup from the Pelican Staff: Keep the oil changes at 3000, or 5000 max. The EPA is on the car companies to lengthen the oil change intervals, but it's not good for the engine. The oil doesn't necessarily get broken down, but can get contaminated with gas which is bad for the oil. This happens when the engine ages and gas, etc leaks past slightly worn-out piston rings.

As for winter oil, I do recommend switching to a lighter-weight oil for winter, especially if you live in the northeast or up in Montana. - Wayne at Pelican Parts
John Comments: I just rebuilt the engine in my '94 325i my haynes shop manual says to use 20w-50 oil, is that the correct oil or what would you reccomend? It is a street car sometimes driven aggressively
August 7, 2009
  Followup from the Pelican Staff: That's a heavyweight oil. I would use that in the summer when temps are a bit warmer, and switch to a lighter weight oil if you live in a climate where it gets colder. - Wayne at Pelican Parts  
chris Comments: Is it normal that my 325XI consumes a lot of oil? I have to add oil every 500 miles.
April 25, 2009
  Followup from the Pelican Staff: That sounds very high. I would read through my engine rebuild article and take a look at some of the things that might be causing this high oil consumption. Here's the link: - Wayne at Pelican Parts  

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