Slick 50 and Synthetics

mgdvhman

For years I've used Slick 50. Back before it was
$15 a bottle..I got it from mail order in the back
of car mags for about $60 a quart? Has it
helped?..I don't know. I can say I've had no major
engine problems in any of the cars I've driven
hard..(which is all of them)

I have a 2000 3/4 6.0 Silverado and it's got about
700 miles and ready for the first Oil change.
I've never used Synthetic..and will be using Mobil
1 5-30. Should I still use the slick 50? I
suppose i could look up slick 50's web site or
somewhere else....but I have had fun getting
answers here.

Lemme here what you have to say.

Any conflicts with synthetic and this product?

Any input would be great.

Thanks

- Tim

markbuck

Lots of talk in the Maint. and Repair Conference.

I think you have been successful in spite of your use of Slick 50.

And the way I make my living is as a PTFE process engineer for implantable medical products.....

I'd run 10W-30 Mobil 1 if you live where it is warm......

I'd also wait until another oil change, and run conventional until then.

mgdvhman

It be cold here in Michigan. 5-30 might be a better choice. maybe 10-30 in spring/summer.

Wait for what?....Slick 50 or synthetic?...and what's your theory?

I know we have duked it out in past topics...perhaps we can get along here?..LOL!

- Tim

bslova

I've used Mobil 1 for many years on six vehicles.
I was told initially not to switch to Mobil 1 until after rings set completely. I believe in it and will use it in my 2000 Sierra after the second oil change. I read an article shortly after it first became available in which Mobil 1 was compared to conventional oils. The oil remained cleaner longer and wear was less.

Rocles

Tim,
If anything, teflon additives kill your oil filter life and in turn causes real damage to your engine. Being a motorcycle enthuist as well as a slack-jawed roofer, ANY cycle mag will bash any additive. The teflon clogs the filter and in turn allows the debris to continue to flow in the engine. Notice how Slick 50 has backed off it's guarantees? Most manufactuers recommend against that type of additive. I'll trust Ford,GM,Honda and Harley before the snake charmers in CA selling sLICK 50.

mgdvhman

I figured both was overkill.

I've heard to wait for the rings to seat...but wouldn't ya think at 750 they be seated by now?

So I should hold off on the Mobil 1 until about 4000?.....doesn't seem right. Vette's come with it from day one?

Anybody else have 2 cents?....I'll even take your 1 cents.

Thanks for all so far.

- Tim

Rich

mgdvhman,
Most new vehicles come with a high chrome content rings. These can take as much as 25,000 to seat in. I would wait until your oil consumption is drastically reduced between changes before using the Mobil 1.
Rich

mgdvhman

Drastically reduced?

It's not using any now?

Almost 800 and still no first oil change yet...we shall see what I decide. Probably skip first change with it...but perhaps after.

Thanks

- Tim

mfreeman

I'm going to drive around 500 miles and change all fluids to synthetic. If it takes longer to break in the engine fine, but these engines have such tight tolerances that they are basicly already broken in.

When I was dreaming of the corvette the choice was easy, redline oil through out the car. On a truck I'm thinking Mobel 1 is good enough. What do you think?

Automatic transmission, did anyone change out the fluid after breakin. I was thinking about having them pump it out, but I don't know if I want to drop the pan on a new truck.

What are people using in the rear dif?

Mike

P.S. SLick 50, I used it in my second car and the engine oil pump went out at 100,000 miles. From what I have read Dupont tried to NOT sale it's teflon to Slick 50, but Slick 50 took them to court. Dupont still says that teflon should not be used inside engines. I also read a report about Prolong which said it worked great, BUT if your engine parts were exposed to air (i.e., when you stop your engine and let all the oil drain into the pan) they would start rusting at a lot faster rate. Conclusions, what may be good for racers may not be good for Joe Public.

mgdvhman

Although I've always taken it easy on the break in for 500....I've been told by some that you should break it in the way you intend to drive it. Now that would be kinda harsh in my situation. Oh well..I took it easy.

Anybody else got a theory?

- Tim

markbuck

Silverado, I went thru about a qt of oil once I started womping on the motor as part of completion of break in. No oil usage since then even when operating at WOT for 15 minutes at 4,300 rpm (towing uphill from 3,000 to 7,000 ft)

BS on the break it in the way you intend to drive it. Spend the first 1000 miles doing low power city driving.

While I make my living understanding how to make PTFE (teflon and other brands) into salable products, I can't imagine the value of using it in an internal combustion engine except maybe as a piston skirt coating.

I try to baby my new race bikes (come with teflon coated piston skirts) for the first tank or two, then gradually hammer on it more and more until it is fully broken in.

mfreeman - I wouldn't worry about changing fluid, the new DexIII/Mercon stuff is almost as good as Mobil 1's old synthetic ATF. If I were to change, I would certainly drop the pan and change the filter. In fact, would rather change the filter and reuse the ATF give the choice. I have dropped many tranny pans and never had leak problems......

mgdvhman

So much for waiting until 1000 miles.

I stayed under 55 for the first 500...then hit the highway for about 120 miles at about 70-75. I've been driving highway/city..going about 55 in city..70-75 on highway. Had it up much higher to see what it feels like...but no serious ragging. About 800 or so and ready for the first oil change. Going to skip Slick 50 and go with Conventional oil for first change. May change it at 3000 still?....We will see.

- Tim

Rocles

mfreeman,
Good memory on the DuPont battle with Slick50. All must wonder about Slick50's claim if the actual maker doubts its use in engines.

markbuck

I think you have a good plan going. I did my first change at 900 miles, second change at 3000ish, and have been on the 3000 change since then. I'm doing the 9000 change this weekend, and am gonna reset the oil minder and just follow its schedule from now on. It triggered at 3,400 and then 3,600 miles later.

Rich

mfreeman,
Isn't the T-Plus product made by DuPont? It's a Slick competitor.

f220swift

We break all motors in as we would intend to use them. Normally, after playing around for a few hundred miles, myself or a family member will hook up to the 32ft travel trailer and head to the bridge(Mackinaw Bridge). This is about a 500mi round trip and we do not baby it. I personally feel that a motor will run stronger and longer with this type of break in. Of course these are Ford trucks. One reason I like Ford motors is that they hold 6 quarts of oil. Over the life of an engine I think this makes a difference. Used nothing but Valvoline 10w30 with no problems.

rotorray

Per Consumer Reports, whatever oil you use make sure it bears the Petroleum Institute "star". This ensures that it meets PI's test criteria. Some oil weights do not bear this star, even from the same manufacturer. Castrol 5-30 may not have it but Castrol 10-30 does. Per CR, if it bears the star then shop for price because oil is oil after that, with minor differences in additives. Synthetics are the way to go for heavy hauling, per CR, but for the average driver extra cost does not warrant their use, especially with 3,000 oil changes. My theory is with an $8,000 engine what's a few bucks more for a quality oil like Mobil 1. Cheap insurance, for sure. Synthetics take the beating better, especially in HOT climates and towing conditions. Just let your engine break in properly (I know 'vettes come from factory with it), make the switch, and feel secure that your engine is happier. Forget Slick 50. A quality oil is ALL you need.

rudy1197

Ive used Mobil-1 for almost 20 years now. Use 15-50(red cap) in summer and 10-30(green cap)in winter. The longest time period I've used it was on a 1987 Chevy 350 fuel injected 4X4 that I bought new. I just sold it because I had the itch to buy the new 250SD diesel. It really was a great truck. Had 176,000 miles on it and it ran perfect - like new- no kidding. I changed oil at between 7500 and 10,000 miles for 13 continuous years on that truck. Buy the way, even after 13 years, there was no engine oil leaks. I usually had to add 1 more quart over the period of 10,000 miles because the oil is thin. Its been like that from day one. I will continue to use Mobil-1 on my other vehicles including air cooled lawnmowers, motercycles, etc. As far as SLICK-50, dont put it in your engine. Its a bad idea to put ANY kind of solid material into your engine oil.

markbuck

BTW, Mobil makes a synthetic diesel oil called Delvac 1 in 15W-40 if you are a M1 lover.....

davids1

Have to throw in my two-cents worth. Unless you are using your truck in SEVERE service, changing the oil every 3000 miles is a bunch of HOOEY! This interval is propaganda thrown out to the public by, who else, the motor oil manufacturing industry. Read your owners manual and use the service schedule that most accurately matches your usage. The oils today are superior quality. Keep receipts for oil, filters etc. if you do your own changes. Oh well, maybe that was three cents.

mgdvhman

yeah....it is a crock. but it must be a crock that works. About 7500 is fine..and 10,000 for synthetic..but still we find ourself doing it at 3000. Must be the old dog-new trick thing?
When i go past 3000 by a thousand or 2...that's why i don't worry.

Oh well

- Tim

mgdvhman

Maybe that's why i still do it every 3000...Old Dog no like new tricks.

- Tim

vince4

It may be a bit of overkill but I think it's cheap insurance if you're going to keep your vehicle a long time. I've used 3000 mile change intervals on my 82 Honda and with 170,000 miles on it a cylinder leak-down (pressure) test gave results like a new car. For those of you that lease or get a new truck every few years, follow the recommend interval and do something else with your time.

Rich

In my '92 7.3L I changed the oil every 5,000. Used a 30 weight for diesels by Penzoil. The ONLY time that it used enough oil to add between changes was when I would run 1000 to 2000 miles at 80 and above. If I drove sanely 65-75 then it barely used any oil at all. This truck was going strong at 135,000 when I traded for my Super Duty.

Rich

norm10

I have an '88 K3500 4 X 4 with a big block 454 V-8. I've used Mobil 1 15-50 in the summer and 10-30 in the winter with a WIX oil filter. I change oil every 10,000 mi or 1 year, whichever comes first. I now have 181,623 miles on the truck and have had no real problems. I pull a 11,000 lb 5th wheel travel trailer from time to time and that is the only time the engine uses oil. I'll use 1 quart of oil in the 10,000 mile/1year cycle. I use an additive that was recently introduced called "Prolong". I don't know what affect it will have. Time will tell. My previous truck ('72 Chev C-20 w/ 400 c.i. V-8) had 240,000 miles on it when I pulled the engine and transmission, replaced them with factory new eng/trany and my son is still driving it. He has 512,600 miles on the truck now. I'm sold on synthetic oil and auto trans fluids.

stevek

I just changed my oil and (on an advice from a friend)the first time ever, I used some "snake oil" (slick50). The only thing I have notice so far is a significant reduction in exhaust noise. The vehicle is a '97 Chevy K1500 with the 5/7L Vortec in it, with 65K miles.

z71bill

Anyone who puts slick50 in their new engine is nuts. You would be better off throwing you money into the lotto - at least then you have a 1 in 20,000,000 chance of getting a pay back. If this stuff worked one of the auto makers would be recommending it.

Use the weight & type of oil that is recommended in your owners manual.

I have never seen an owners manual recommend 15W50 oil. This should only be used if you have a high mileage car the uses oil(rings are shot). It is not true that heavy oil does a better job of lubricating. In fact the opposite is true for todays engines.

My owners manual (99 silverado 5.3) says use 5w30 as the 1st choice, 10w30 ok if temperature above??. (It also holds 6 quarts)
The only difference between 5w30 and 10w30 will be the viscosity of the oil at cold start up. After the oil is warm they are both the same 30weight. The 5w30 does a better job at start up because it is thiner and flows easier, getting to the moving parts faster. I live in Houston and it is hotter than hell - but I still use 5w30. Most dealers in the area are 20 years behind the times - they say use 10w30 unless it is below 0 degrees. The are full of [non-permissible content removed]. The real reason they want you to use 10w30 is that is all they have in bulk and it saves them $.10 per quart.

jaijay

Up here in north country I will be using Mobile-1 0w-30. I have used this before in a van we had. The van sat out in -10 degree weather for 10 hours before we got in it to go home. When I started it is was like the engine was sitting in a heated garage. Smooth idle, no tapping or knocking. The engine loved it. I thought for sure with the very cold weather it would have a tough time to crank over. Batteries don't like super cold weather either. However after that night I was a firm believer in the stuff.

The lower the first number on the oil weight indicates the flow when cold. I have had no problems with the van and as soon as my 99 Silverado requires an oil change in it will go.

powerisfun

I wondered about how the 0w-30 compared to the 5w-30. I just recently purchased two 5-quart Mobil-1 jugs of 5w-30 for 14.97 at Wal-Mart (love that store!). They didn't have the 0w-30 in the
5-quart jugs, but if they did, I would have gotten that. The winters here in northern New Mexico seldom get down below the 20's, but still the lower the viscosity at start-up the better (well, there's a limit to that, of course. It would still have to have enough viscosity to lubricate properly). Good luck!
-powerisfun

mckain

Just had to add my nickel.

I've been using it since 1975. My first new car, a 75 Chevy Monza 262 V8 4-Speed. It flew, matter of fact it still does. I have 110K miles on it now. It's now in storage. I changed the filter every 5,000 dumping the old Mobil 1 from the old filter to the new...screw it back in. Changed the oil every 25,000 miles! Yes I have changed it four times. The motor still purrs not even a lifter tic.

This is great stuff, don't be afraid of going beyond 3,000 miles guys. Extended changes are no problem for this oil.

I use it in everything from the lawnmower to the kitchen fan.

I was sold long ago when one cold (-25F) morning I thought my car would never start. Well it cranked like it was in southern Calif.

Its really amazing stuff.

-Jim

z71bill

25,000 miles between changes --why? If you go to the trouble of changing your filter why not go all the way and replace the oil too. I will admit when my Nissan got over 100,000 I would change the oil and not the filter to save time (this was recommended in the owners manual)

After that many miles the oil had to be black, black black. It is not the oil that goes bad, it collects dirt & acid from normal engine operation.

Are you concerned about voiding your warranty?

Why spend $20,000 or more on a car/truck and then not spend $20 on normal maintenance?

felix4

The larger the number (viscosity) difference, the more unstable the molecules in the oil. For example 5w-30 is less stable than 10w-30 and 0w-30 is even less stable than both. All this unstablitiy means is that the additives in the oil that protect your engine have a shorter life span. Don't just take my word for it (and all auto manufacturers), go to a lab and see for yourself. You should try to stick to as little a number (viscosity) spread as possible. Just my $.02.

arkie6

felix4,

your reasoning applies to conventional motor oils; however, synthetics require fewer viscosity improvers than conventional oils to achieve the wider viscosity profile. It's the viscosity improvers (VI) that screw things up since they do not provide any significant lubrication qualities. The synthetics remain free flowing at lower temperatures than conventional oils and can thus start out with a higher base viscosity than conventionals. This allows them to achieve a wider effective viscosity profile while actually having fewer VIs than the organic stuff.

Just my $.02

eliteone

Benchmark tests and specifications reviewed to date prove synthetics beat petroleum-based lubricants every time, every test (4 Ball Wear, Volatility, Pour Point, Boundary Layer Surface Psi, V-Block Wear, etc.). Viscosity stability over time is superior in synthetics (regardless of "W" spread) plus synthetics are superior in countering negative effects of combustion byproducts. Synthetic molecular make up is natural Gas and hydrocarbon based. BIG NAME additives are often unstable and rarely sold in clear bottles since contents settle into glue-like masses (same effect at bottom of crankcase) which can often result in hydrochrloric compound formation (either Ph# acidic or can block oil screen pump pick up point). We are prmoting only 3 brands of additives, one approved by the FAA for aircraft engines. The key is to eliminate or reduce dry start wear and also protect metal with high psi boundary layer protection. We only believe in 4 on the market. Some treat the oil and some treat the metal. We believe in treating the oil and the metal for superior results, as manifested by dyno records and customer testimonials (including Marine, aircraft and other applications).
www.EliteOne.com

markbuck

How about cost? Most folks that take care of their vehicles and change oil frequently have the vehicle wear out for other problems other than engine wear.

I'm gonna go 150 to 200K running Walmart tech2000 synth blend at $1.25 per quart. If synthetic was so superior, I would bet that the OTR diesels would be running it.

I do run synthetics in my race bikes for the reasons your list, but just don't see the value for my 10yr around town vehicles.

mgdvhman

Heck...even with Reg.Oil...the manual says every 7500. 3000 is overrated big time.

- Tim

z71bill

I doubt I have sludge build up after 3K miles. You are right about one thing I have not seen the inside of any engine I have bought new. Never had the need to open them up. The information I read in several car mags concluded that synthetics are slightly better in some conditions - But also went on to say the miles/months per change for synthetic and regular oils is the same... I am not saying "I want to save $20 so I use the cheap oil" I just think you are better off using regular oil and changing it more often. I only drive my truck about 800 miles a month (mostly city stop and go) it only gets changed about 3 times per year. I alternate between doing it myself and taking it to the dealer so I have a record of it being serviced - for warranty reasons.

I can not understand why anyone would go to the trouble of changing the oil filter and not changing the oil. I saw one post where a guy actually said he dumped the oil from the old filter into the new filter. If you really "treat your engine the best regardless of what I may get by with" as you say why not change the oil when you change your filter? Sound to me like you need to take your own advise.

ww00650

I think the I can explain what is intended here. Having a vested interest in maintaining my own vehicles, I've tried to keep myself up to date on the latest beliefs and hype.

The reason behind the synthetic oils is the Purity of oil molecules. Few or no additives to breakdown. If there isn't a breakdown of the oil, then why change it? Even GM says the recommended period between changes is 7500 miles, without regard to it being conventional or otherwise.

One would still want to change the filter more often than the oil. Why? While the synthetic oil will last much longer, the engine is still wearing away and creating it's own contaminants of metal, combustion byproducts, etc.. These Should get trapped in the filter. Too many particals in the filter and it will stop doing it's job.

How many miles do you get between oil and/or filter changes? It depends on what you believe and who you listen to.

Conventional Oil / Filter companies say : 3000
Why do you think they say that? Hmmm. You don't have to be a brain surgen to figure this one out.

GM says : 7500 miles
It's their warranty on your 5.3. You think they would put unneccessary risks on their bottom line.

Synthetic Oil companies will claim whatever they have to, to win your business.

Again, it depends on what you believe, and who you listen to. In my car I use conventional oil every 3K. I never planed on having it this long. In my 93 Honda VFR crouch rocket I have used slick 50. Soon after, I noticed a slight tap from the heads, and no other positive or negative results. No change in performance or oil cleanliness. I'll never use it again.

When I get MY new LT I'll be using a synthetic at the first oil change. Most likely mobil1. A friend has been using it for years on his Mustang, changes his oil and filter every 5K, and I've seen the inside of his valve covers(he's a performance freak). Spotless. He swears by it, and that is the best recommendation I can make.
Word of mouth is by far the best way to go.

markcord

I just picked up my 2000 V10 Ram. Dodge must agree with GM. The dealer says "your first scheduled checkup and oil change is at 7500 miles." I looked thru the maintenance schedules and the heavy duty schedules for the 8.0L also recommend oil changes at 7500 miles. The manufacturers must know what they're talking about. I personally plan to change for the first time at 3000 then switch to Mobil 1 and change at 5000. Anybody out there see any problems with this? I would think the valves should be seated by then. Any recommendations would be greatly appreciated.

pcheng

The color of your oil is not dirt. The change in the oil color is mostly due to blow by gasses (essentially exhaust) that blow by the piston rings during compression. The gas reacts with the chemicals (and heat) in the oil changing the color of the oil.

The color of the oil (that is caused by blow by gasses) does not directly correlate with its ability to lubericate and dissapate heat.

Oil that comes out of a race car after it has been driven 300 miles comes out almost black. The oil from a car that drives under 55mph every Sunday to the market, after 1000 miles, and 8 months, has very light oil. The oil from the regular car is much more along in its lifecycle than the 300 mile race car. Break down of oil has a lot to do with the oil being heated and cooled over and over again. The more heat cycles you put on a oil the more it aborbs moisture and starts to break down.

If the color of the oil were dirt, then the person who changes the filter all the time would have the right idea, and the oil would always be amber colored and never go bad.

mgdvhman

That shower theory is killin' me boss!

I changed at 980 with regular Mobil and a GM filter

Going to change at 3000 with Mobil 1 5-30

After that every 5000...and have not yet decided on GM filter or Mobil 1. perhaps GM to keep a warranty record..kinda..

- Tim

z71bill

I will admit I am not a mechanic, have not done an engine rebuild for 20 years. But at one time I could fix anything - rebuilt the engine in my 69 Chevelle 396 when I was 18. Helped friends with valve and ring jobs, carb rebuilds replace clutches - what ever needed fixing.
The way engines are today - all the computer stuff- I will admit it is above my capabilities..and I really don't have the time or the right tools. I guess the good news is engines are more reliable and don't have as many internal problems.

You may be taking this oil stuff to personal. I had no intention upsetting you or anyone. I have not seen anyone get so upset since I told someone in a Toyota topic that I thought the Tunda back seat was to small. Change your filter if it makes you happy - it still seems like a waste to me. Hell maybe we should start a topic about tire rotation - that would really get everyone excited.

Pcheng- I understand you race car VS 1,000 miles in 8 month example. It is not just miles but time.

markbuck

I'm with Z71bill on most of this issue. I don't rebuild car and truck motors anymore, but did in the old days. Also did a science fair project on comparison of mobil 1 vs conv way back then on B&S lawnmowers. I work as a Mechanical Engineer, and my passions include having some knowledge and understanding of internal combusion engines.

I run synthetics in my street and dirt motorcycles. Run relatively cheap oil in my tow vehicles, pressure washers, lawnmowers, ....
My tow vehicles never overheat, and I don't think it's possible to measure the difference in engine temps related to oil type (my opinion)

ZBad71, feel free to keep offering your opinion, but please allow the other readers to draw their own conclusions.

z71bill

I know the Silverado has Synthetic gear oil in the rear differential. But no change interval is specified in the owners manual. Does this mean you don't have to change it?? The 98 Tahoe my wife drives has the locker and it uses regular gear oil. It needed to be changed at 3,000 miles and then every 15,000 miles or 2 years.

My Silverado has 5,000 miles - is it time for a differential oil change??

Anyone also know what GM charges for a quart of synthetic gear oil. (I say quart but the regular gear oil they sell comes in 22 ounce bottles) The Mobile 1 75W90 synthetic gear oil I saw at AutoZone said " not approved for limited slip differentials" Whats up with this - if mobile 1 is so good why is it not approved for limited slip differentials.

The strange thing is the Silverado has a drain plug in the rear differential but no change recommended in owners manual. The Tahoe has no drain plug, you have to take the cover off and replace the gasket when you change the fluid. To me this seems [non-permissible content removed] backwards.

I would like some information on this before next weekend. The Tahoe is due for a change and as long as I plan on getting dirty and oily I might as well do both of them.

mgdvhman

My Local Trans shop told me every 10K for a Limited slip....does that mean locker too?

Dunno

- Tim

zbad71

Thanks for your post. I think its cool to get real life experiences like this, especially 25 years worth.

My Dad, although he for some reason felt the need to buy his wife a Ford V10, has always been a loyal Chevy owner. He is still the original owner of a 78 K10 Reg Cab 4X4. I think it was the first year for the manual locking hubs.
He is on the second engine. The first had over 200k miles on it before replacing. The one in it now has a little more than that. SAME TRANSMISSION and going strong!

He has always used synthetics in his trucks and continues to do so today. He swears its the only thing that kept oil blow by past the rings. The truck lost some compression upon reaching the high mileage and eventually leaked oil, but never burned a drop and to my knowledge doesn't on the second engine either.

I will always use a good synthetic, no matter what the cost. I feel it pays for itself in the long run

z71bill

Ok so you go 10,000 miles between changes - how long does it take you to put that many miles on your car? If you have 300,000 miles on a 96 you must drive at least 75,000 miles per year. Unless you are a cab driver or deliver pizza they must be mostly hi-way miles. I could see going more miles between changes but it takes me a year to put 10,000 miles on my truck. You drive that much 6 weeks. If I drove that much I would have to change my oil every other weekend - If that was the case I would be switching to synthetic oil tomorrow!!!

mckain

I agree with you, If I drove it 10K per year I'd be changing oil&filter twice a year anyway. Like I said you need to do what makes sense for you (people sometimes forget about just using common sense for the situation you're in, most everyone has a different situation, not putting you down or anything) ALSO you need to do what you feel comfortable with.

By the way my post said that my 96 Saab had 95,000 now and I wanted to drive it for 300,000. Sometimes it does 200 miles a day sometimes its just around town. My wife is a contractor (no pizza's) and her assignments vary, I still do my 5K/10K thing. But it might be every month or every three, it depends. If it was six+ months I'd probably change it then regardless of miles. For many years we have averaged 25K-35K on each of 2 vehicles and 10K-15K on the third (usually a truck or van). We spend alot of time in vehicles communiting to work and shuttling our seven kids around.

One last quick story, in 67 my dad gave me his 62 Impala, little 283 V8. I ran that car through high school and college and put another 100K on top of my dads 90K (no doubt the second 100K was a lot rougher on that car, the 5 trannies I put in it prove that). I changed the oil every 3K (no synthetic then). That was the recommended interval back then. When I took it off the road the motor was using oil and it was noisy (lifters) and it had sludge built up real thick. I was comfortable with that and really thought I accomplished something putting that many miles on it.

Then I started using synthetics and it is a night and day difference. If you live in a cold climate you will hear the difference. If you don't you will have to measure the difference over time. But like I said every situation is different, some guys lease and just use a good oil and its done.

Good luck, I'm sure everyone is doing what they think is right. As I said before I just wanted to let people know what has happened to me using synthetics.

-Jim

artp

I'm not a mechanic but I change my own oil sometimes. Whether it's a brand new truck or an older truck I've always notice a fuel smell to the old oil. I realize gasoline and engine oil are both petroleum based, but doesn't it make sense to change the oil with the filter to get rid of fuel residue? Won't the fuel residue break down the oil?

regarding manufacturer 7500 mi. interval recommendation:

I asked my mechanic, who is a friend I trust. He says, they want the engines to last for 100k (well past the powertrain warranty), then want you to buy a new vehicle. There is also a statistic called "maintenance cost" for every vehicle. Obviously a 7500 interval will have lower "maint. cost", thus creating a lower "total cost of ownership". Looks good on paper and to the JD Power people.

To support the theory, there are some fluids that should obviously be changed, such as power steering fluid and brake fluid. some owners manuals ignore changing these fluids completely.

FYI: Saw a study which proved the most popular brand of oil filter, was complete junk. Can't remember the WEB site to back it up. The brand was Fram.

artp

Every engine has a small amount of blow by. The last oil change I did was on a new truck with 3700 miles. Do you think this is because the engine isn't finished breaking in?

z71bill

I don't know about fuel in your oil but if you live where it gets cold (below 0) and you only drive a few miles and don't ever fully warm up your engine you will get condensation (water) in your oil.