Which Motor Oil Do You Use / How Frequently Do You Change It?

[stroke]

A recent conversation with my father-in-law about motor oil sparked my interest in learning more about it. I have always used conventional motor oil with the mfgr's recommended oil viscosity (currently 5W-20 in my Ford Ranger) and changed close to recommended OCI (I will go about 4k in my truck). However, I'm considering switching to fully synthetic 5W-30 or 10W-30 (probably the latter, since I live in south Mississippi and temperatures seldom drop below freezing, and if then they normally won't drop below 20F) and an OCI (oil change interval) of about 10-15K (Castrol, for example, guarantees extended drain interval up to 15k with Castrol Edge (http://www.castrol.com/castrol/sectiongenericarticle.do?categoryId=9027819&contentId=7050795)) with a filter change every 5k.

However, I've been reading a lot about why some mfgrs recommend 5W-20 and I've read at almost every source I've visited that it's because of the CAFE (Corporate Average Fuel Economy). I've found sources (here (http://www.firstfives.org/faq/oil/oilartcl.html) (my favorite writeup thus far), here (http://www.nhtsa.gov/cars/rules/cafe/overview.htm), here (http://www.nordicgroup.us/oil.htm#The 3000 Mile Myth), and here (http://www.smartsynthetics.com/articles/5w20oil.htm) to list a few). Basically, I've gathered that the gov't requires mfgrs to supply a sufficient amount of fuel-efficient vehicles to offset less fuel-efficient vehicles in order to maintain a certain CAFE overall in their fleet. By recommending 5w-20 oil, which I've read only increases fuel efficiency a minute percentage anywhere from .5% to 1%, mfgrs are able to increase the fuel efficiency on their overal fleet by a reasonable margin. The result, I've found, is that (with the exception of only one model that I've read about, and I can't recall which one) 5W-20 is not necessary unless driving in fairly cold climates (down to ≈-30F). In most cases, 5W-30 or 10W-30 are very safe. Also, I've actually read (this link (http://www.firstfives.org/faq/oil/oilartcl.html), listed earlier, also hits this very thoroughly) that fully synthetic oil can be changed after 20k-30k (which I wouldn't consider regardless), but it is reasonable to consider an oil change of fully synthetic oil every 10k-15k, and 3k changes (even with conventional oil) are outdated and no longer necessary. However, many oil mfgrs still push it to sell more of their product.

Anyway, what do you use, how often do you change, and what are your thoughts?

[flyboy]

When Mobile one which was the first synthetic to hit the market my Dad knew the local distributor. The distributor had a big lincoln that he had driven close to 100k miles on mobile one before changing the oil as a test for the company and it was only mildy dirty. My Dad switched to it in his Cadilac, changed it after about 5 k miles since it had run dino oil for 40k miles, then went 25k before the next change and it was amazingly clean.

If I was running synthetic I wouldnt think twice about going longer intervals myself. As it is with regular oil I go 7k most of the time as I commute mostly on freeways.

[MiamiE]

For right now my truck is under warranty with Dodge so I let them do it every 3,000 miles for the $20 they charge. That way when they screw it up, which they already have once, I can blame it on them. After my 36,000 miles I will go to Mobil 1 and change every 5,000 miles.

[DeeDubya]

I prefer changing the oil myself on my personal car/truck. Every 3k, Mfg's recommended weight ('08 Corvette and '08 Tundra) which is 5w20 full syn. The Tundra uses a cannister type filter so it is messy. You know, hot motoroil running down your arm into your armpit, the wind blowing the oil past the catch can onto the driveway, dropping the plug into the catch can, a severe neck cramp from holding your head up and cocked to the left, it's a blast.

[stroke]

If I was running synthetic I wouldnt think twice about going longer intervals myself. As it is with regular oil I go 7k most of the time as I commute mostly on freeways.


For right now my truck is under warranty with Dodge so I let them do it every 3,000 miles for the $20 they charge. That way when they screw it up, which they already have once, I can blame it on them. After my 36,000 miles I will go to Mobil 1 and change every 5,000 miles.

both very good points, which reminds me I forgot to mention I am out of warranty and most of my driving is done on state roads / interstates at 55/70 mph, respectively. Very little stop n go traffic for me.

[BesstR]

I have 290,000 miles on my Ford F-150. I just switched to Mobile One. I use the 10w-40 due to the high miles. The truck runs much better on it. My wife thought she was doing me a favor ant took it in for an oil change. I do not know what they used but it rattles right now. I did not have that with the Mobile One.

[smokinghole]

I swap between 5W in the winter and 10w in the summer. I change ever 5K and don't feel the synthetic can be justified for my use.

I read a very indepth article about oil and the thing that makes synthetic advantageous over conventional is not the length of the oil change but the resistance of the actual lubricants in the oil to high temperatures. The hi-performance vehicles that have non hi-po counterparts like Cadillac CTS the regular model is conventional oil I think, and the CTSV is synthetic. The reason being is because the synthetic can withstand the heat produced by the higher compression engine in the corvette motor balancing out the need of an engine oil cooler with conventional oil. If I could find the article again I'd love to share. It was written by a GM oil specialist or something like that. Basically it said the molecules responsible for the actual lubrication qualities of the oil are more stable than conventional oil especially at high temps.

[DeeDubya]

I swap between 5W in the winter and 10w in the summer. I change ever 5K and don't feel the synthetic can be justified for my use.

I read a very indepth article about oil and the thing that makes synthetic advantageous over conventional is not the length of the oil change but the resistance of the actual lubricants in the oil to high temperatures. The hi-performance vehicles that have non hi-po counterparts like Cadillac CTS the regular model is conventional oil I think, and the CTSV is synthetic. The reason being is because the synthetic can withstand the heat produced by the higher compression engine in the corvette motor balancing out the need of an engine oil cooler with conventional oil. If I could find the article again I'd love to share. It was written by a GM oil specialist or something like that. Basically it said the molecules responsible for the actual lubrication qualities of the oil are more stable than conventional oil especially at high temps.

Yes GM specs Mobil 1 5w30 for the Corvette although I'm sure other good full-syn 5w30's would be just as good.

[Wink]

I was curious about this myself, I have a chrysler aspen v8 hemi I always go with whats recommended 5w-20. I change it about every 5,000 miles and I change it myself. As far as I know its all good! I also just added a quart of lucas, don't really notice any difference?

[Tegu]

Yes GM specs Mobil 1 5w30 for the Corvette although I'm sure other good full-syn 5w30's would be just as good.

Anything that meets GM4718M spec should be just as good, I use mobile one or Amsoil in my 08 vette

[DeeDubya]

I was curious about this myself, I have a chrysler aspen v8 hemi I always go with whats recommended 5w-20. I change it about every 5,000 miles and I change it myself. As far as I know its all good! I also just added a quart of lucas, don't really notice any difference?

I've never used Lucas oil additive but always add Lucas fuel treatment to every fillup. It is an upper cylinder lub, fuel pump lub, injector cleaner and is reasonably cheap as it only takes 3oz/10gal.

[stroke]

just a note: I don't think there's anything wrong with using 5W-20 oil, especially for some brothers further north. However, on the gulf coast the temps sometimes reach 100, which is why I'm considering upping the viscosity. the 5W-20 doesn't hurt, but maybe the 5W-30 or 10W-30 would be better.

Also, I read that 10W-30 would be better than 5W-30 (assuming the climate is appropriate) because it covers a smaller range of temperature resistance. As a result, it requires fewer additives and more base oils which should help it last longer.

It's also worth noting that I've read in several place that the majority of oil additives have been proven to be ineffective or actually counterproductive and/or harmful to your engine. I looked further into fuel additives, but I didn't look very far and didn't come up with much. Any info on that?

I found several graphs showing the appropriate temps for each viscosity, but I actually came across an article this morning saying that SAE doesn't actually publish the standards, or at least thats what I gathered from it (I may be mistaken, please correct me if I'm wrong). Here's a graph that seemed pretty average though:
http://www.aa1car.com/library/oil_chart.jpg

[Tegu]

Also, I read that 10W-30 would be better than 5W-30 (assuming the climate is appropriate) because it covers a smaller range of temperature resistance. As a result, it requires fewer additives and more base oils which should help it last longer.





I'm no oil expert. I live in Texas so could use 10w30 but I would think the 5w30 would actually pump easier on start up and at running temperature both should be the same. I dont think 10w30 would be better for any reason, and if you run synthetic the additive issue shouldn't matter. Even if the oil lasted longer 5w should be better for your car since it pumps easier on startup and lubes the engine quicker.

[stroke]

I'm no oil expert. I live in Texas so could use 10w30 but I would think the 5w30 would actually pump easier on start up and at running temperature both should be the same. I dont think 10w30 would be better for any reason, and if you run synthetic the additive issue shouldn't matter. Even if the oil lasted longer 5w should be better for your car since it pumps easier on startup and lubes the engine quicker.

Good point!

Anyone know the difference between Castrol Edge and Syntec?

[Tegu]

Good point!

Anyone know the difference between Castrol Edge and Syntec?

I heard Edge is Syntec with a few extra additives and the 15,000 mile statement.

[Wink]

Very informative!, I heard good things about the lucas fuel additive, when ever im in the aisle most of time the people at the store push lucas products! Based on knowledge does anyone know if oil additives actually hold its weight or are they just a waste of money?

[Jetexas]

Mobile 1, 10W-30 every 15K on both cars...:driving:

[dpricenator]

10w-40 1 quart every month....lol

[Craig Mac]

synthetic blend every 5K

[eric_f]

I use Rotella T6 15w-40 in every reciprocating engine I own aside from two-cycles. I've used Rotella dino on everything in the past and it protects very well, just gives you a little lower MPG in my opinion because of lack of friction modifiers. In the car, I'll go 10k, motorcycles 5k.

Don't forget the filter, they're as important if not more so than the oil. I trust Purolator PureOne's

[stroke]

Funny you mention the filter... search for oil filter on youtube and see what comes up. I used to buy Fram filters all the time, but never again! You'll have to see for yourself, I can't put it into words. I'll probably stick with Bosch, but I'm considering Mobil 1; it's twice the price of Bosch but I think it may be worth it. Feel free to opine!

[blooz4u]

You're supposed to change the oil ?

[Catbert]

I use Pennzoil Platinum 5-30 in all three of my cars: a 2007 Vette, 2010 Equinox and 2005 SSR. I change when the computer tells me to, or 8,000 miles, whichever comes first. I use K&N filters on all of them.

[Crypto Sailor]

I've used full syn after the first few oil changes, and have used 5w20 until recently and started using 5w30 and change it between 5K-10K depending on how I drive. And try to use a decent filter with the anti drip back valve...

[Cigar Cowboy]

AMSOIL Premium API CJ-4 Synthetic 5W-40 Diesel Oil

[BGC]

Rotella T 15-40 in Duramax. If I didn't buy a 55 gal drum I'd probably be using Amsoil synthetic. They've been doing it longer than mobil 1 I think. I use just Amsoil in my tranny for right now.

[L8A]

Audis are full synthetic and go 10k between services. I have 110k on mine and am sure it'll go a bunch more.

[danthebugman]

I do my own oil changes and have ever since I owned a vehicle. I usually use fully synthetic 5W30 and I usually buy the generic brand. I used to change it about every 5,000. However the last few years I've just been changing it a few times a year (before summer and winter set in). The reason being is that we don't drive the vehicle much (living only 4 blocks from work certainly helps) and it just makes me feel better to know I have clean oil in the vehicle. Depending on how much driving we've been doing I may only change the filter once a year.

Dan

[smokemifugotem]

never buy a car from me...i suck at changing my oil...

[eric_f]

I was reading a while back that the Wally World SuperTech syn oil is actually re-badged Pennzoil synthetic, fwiw. They stamp the same batch codes on both, same contacts on msds, etc. Their filters are more efficient and are of better media than Fram as well. Surprising considering that they're less costly. I don't know anyone that loves Pennzoil, lol, but you can get the same oil for 2/3 the price. :stretchgr

[Stew]

Shell Rotella-T 5W40 full synth every 3500 to 4000 miles.

[itallushrt]

Always Mobile 1 full syn every 5k miles. Also change the trans fluid every other oil change. Current truck has 170,000 miles on it and should be here for another 170,000.

[stroke]

wow, tranny fluid every other oil change? Is this something that should be done regularly, or are you just extra cautious?

[itallushrt]

wow, tranny fluid every other oil change? Is this something that should be done regularly, or are you just extra cautious?

Extra cautious because I tow a ton of crap with this truck. Haul a boat around about 150 days a year, 4 wheeler and trailer another 30, etc, etc...better safe than sorry.

[stroke]

Extra cautious because I tow a ton of crap with this truck. Haul a boat around about 150 days a year, 4 wheeler and trailer another 30, etc, etc...better safe than sorry.

got it rough! hehe Sounds like my kind of life!

[stroke]

well I went ahead and got some Castrol Edge 10W-30 and put it in my truck. Also got a Bosch oil filter, never using a Fram again! Still debating whether I'll use it for 15k miles, but will surely go at least 10K changing the filter every 5k. Thanks for all input on here, gents!

[CWS]

Mobil One in the Jag and Mercedes 560 every 10K. The Mercedes is an 86 560 SL and the mechanic said it will reduce oil leaks int he older engine sealing gaskets better. Seems to work.

[cvm4]

5w-30 & every 5k miles.

[e-man67]

You don't need to swap weights of oil for cooler/warmer weather. Go with what the manufacture recommends as far as weight. I buy BMW oil for my 525 which is recommended to change every 15K...I change every 8-10k..In the Explorer I use 5w20 motorcraft (factory recommended..I have 106k on it now)...I had a 97 F150 that used 5w30 but had some small leaking seals. I started using Valvoline 5w30 maxlife and it swelled the seals so it did not leak anymore..I would recommend that for cars over 150K in mileage.

[strife]

You're supposed to change the oil? I just throw some kitty litter on the puddles and add a quart each month.

[daniyal]

I use a fully synthetic 5W-20 since its easily available here. As far as the interval between oil changes I'm pretty horrible with those, for one reason or the other its something I never remember to do. Most of the times when I get an oil change the oil is always black and most of the times my engine is running low on it.

[thebayratt]

I usually use Royal Purple Full Synthetic 10w-30. It gets changed out around 4500-5000 miles. Works great, costs alot.

[Stew]

I usually use Royal Purple Full Synthetic 10w-30. It gets changed out around 4500-5000 miles. Works great, costs alot.

IMO, your overpaying for oil. There are a lot of choices that are equal or better than RP for a fraction of the price. Even for the premium oils out there, RP seems to have issues with excessive viscosity loss from shearing among other issues. Oil choice really should based on application, however RP seems to miss the mark accross the board. bobistheoilguy.com is a good resource for research.

[cubancigarman]

where's the 10W-60?

[stroke]

where's the 10W-60?

U drive for NASCAR?

[Burning Man]

I use full synthetic Mobil One in my bucket. It's the only oil that has ever been used and I have never had an engine issue. My car has about 325k miles and still running strong. She burns a little oil but what car doesn't with that many miles. I change it twice a year and top off when needed.

[Headbanger]

Both cars now recommend change oil every 5k. The Lexus goes to the dealer so they can check everything over really good and gets a nice wash and wax job. The Prius goes to the local shop down street from work so I can leave with them for the day. I have no clue what type oil just that is regular stuff.

[cubancigarman]

U drive for NASCAR?

haha.. not quite...but i could be the pace car... 2008 BMW M3

----
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 TWS Motorsport SAE 10W-60 Synthetic Engine Oil

Castrol Formula RS SAE 10W-60 Synthetic Engine Oil (BMW part number 07 51 0 009 420)

[bradb]

amsoil 10w-30 25k high performance

[Humidor Minister]

My oil change is a fortune. 12 quarts of full synthetic Rotella. Cummins turbo diesel w/ a touch over 600hp. :halfgrinwI do it myself and it costs around 80 bucks.

[Stew]

My oil change is a fortune. 12 quarts of full synthetic Rotella. Cummins turbo diesel w/ a touch over 600hp. :halfgrinwI do it myself and it costs around 80 bucks.

Rotella is the Stuff! The guys at the auto parts store always look at me funny when I buy two gallons and hop in my Subaru. :smile:

[hogfarmer]

I've been a heavy equipment mechanic for 37 years. If you keep oil changed regularly and use a reasonable quality oil it doesn't matter if you use synthetic or dino. That said, I run dino in my cars and synthetic in my Harley. The synthetic does have better heat resisting properties.

[Stew]

Synthetics key advantage is time between changes.

Most also resist shearing better than conventional oil, which is important for diesels, Direct injected engines, or anything that produces high oil shear stresses (turbo, direct acting valvetrains, etc.) But that is one of the largest contributors to viscosity break down. Conventional oils usually include additives called viscosity index improvers which help control multi grade oil viscosity across various temperature ranges. These molecules are the ones that suffer from shear stress the most, and this is where synth oil's advantage is clear. Because Synth oil uses synthesized long chain hydrocarbons that help stabilize viscosity and which also happen to be less sensitive to shear stress.

Also, a lot of synth oils include additive packages that can include friction reducers, detergents, or other goodies.

[Humidor Minister]

Actually there is a big difference. Synthetic doesn't break down, just gets dirty. Regular motor oil breaks down over time. Looses its lubricity. I put over 250000 miles on my last truck. When I sold it, the guy did a compression test on it. It was still like new. Unfortunately someone tried to steal it and f'd up the wiring. The insurance company totaled it because it had 320000 miles at the time and it was a 97 Chevy dually. A sad day.

[Mr.Erskine]

In our Chrysler, I change every 3000-3500, and I use Valvoline high mile 5w-30

In the beater that is only driven to and from work, I change every 3000-3500, and I use Pennzoil 5w-30. That car was my wife's when she was in high school, and that's all her dad put in it, and we haven't had any problems, so I just decided to keep using it.

My GSXR goes to the shop, and I would have to look up the paperwork to tell you what runs in the bike.

[BradMc]

I have a 1998 Ford Explorer with 150k I just started to run synthetic Mobil One , it runs like a champ ? looks r a lil hard, but 9 years in MN will hurts the looks of anything...
On the 2010 Toy. PU it is done at the dealer ship, but we do have synthetic oil in it also .....

[Bigdankcloud]

I've been running Mobile 1 Full Synth 5w-30 since I got my 2008 altima coupe. The car runs smoother than alot of other oils. I did try Redline and Amsoil as well. While nice, the hassle and expense to get them isn't worth it when Mobile 1 is readily available.

[joshua]

I just put down 10k but I probably will do it sooner because my ECU is performance flashed and probably burns up more oil with the turbo. The manual for the GTI says 10k is fine, which with modern synthetics and engines usually isn't a problem.

[ljg]

Full syn Lubromoly 5W-40, every 4-5k mi. Was using Mobil 1 before this.

[Stogiecidal]

haha.. not quite...but i could be the pace car... 2008 BMW M3

----
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 TWS Motorsport SAE 10W-60 Synthetic Engine Oil

Castrol Formula RS SAE 10W-60 Synthetic Engine Oil (BMW part number 07 51 0 009 420)

I'm with Mr. Cuban and use Castrol TWS 10W-60 full synthetic in my '02 BMW e46 M3 every 6k-8k kilometers (not miles) even though OCI is set to 25k kilometers. I don't put a lot of kilometers on her as she gets stored every winter and I borrow the wife's car, which uses regular 5W-30 that she probably services closer to the end of the 12k kilometers OCI.

[ItalianCustom]

any reccomendations on a filter?.. I use maxlife 5w30

[c money]

15-50 Mobile one for the M5

[c1ark]

Hey theres no Valvoline VR1 straight 50 on the list?? Just kidding, thats what we run in the race cars..

[Jenady]

A petroleum engineer told me that the synthetic oil that most people drop during an oil change is better than new dino oil. I have used synthetic blend and full synthetic for years.

I decide to try an experiment. Once our '07 past warranty I quit changing oil. I replace the filter every 5K and top it off with new oil. The car now has 95K on it. It uses no oil. I am going to do a complete change at 100K and keep on driving.

btw - I use 5w-30 Amsoil.

[Ted Nasty]

A petroleum engineer told me that the synthetic oil that most people drop during an oil change is better than new dino oil. I have used synthetic blend and full synthetic for years.

I decide to try an experiment. Once our '07 past warranty I quit changing oil. I replace the filter every 5K and top it off with new oil. The car now has 95K on it. It uses no oil. I am going to do a complete change at 100K and keep on driving.

btw - I use 5w-30 Amsoil.

Interesting. How many miles did it have on it when you started this experiment?

[Danilo]

My supra got oil changes every 2500-3000 miles, full synth. usually Total Brand.
My infinityi FX35 gets the same oil, but more like 10k miles or so...

[Jenady]

Interesting. How many miles did it have on it when you started this experiment?

I started at 50K. I am now at 100K.

[Angry_Dragon]

I do Oil analysis every 8K and last oil change with Mobil 1 extended I got to 16K. Very happy that I only change my oil once a year!