[RKBAGUY]

I know the traditional recommendation for oil change is 3000 miles, but that standard has been with us since my Grandfather's day. Given today's motors run smoother and better, and engine oil technology has also improved, what is your change interval? Yes, I know that it depends on your driving habits (city vs. highway, slowpoke vs. leadfoot, AZ vs. ME) but all things being equal, would you say it's alright to push the 3k to 4k nowadays?

[micholob]

I run 5k intervals. I check/add as necessary.

[Squilliam]

I still do 3k on both my 3800 Buick and 2.7 Intrepid

[bh1992]

if you look at the maintenance manuals, you will even see that most cars since the late 90s/early 2000s have suggested longer service intervals. I have seen several manuals where they suggest around 5000 to 7500 miles between oil changes, and with manufacturers using synthetic lubricants in new vehicles it is not too uncommon to see manufacturers list oil change intervals of 10,000 miles.

Personally, I run 5000 miles between oil changes. I know many people who stick with 3000 mile oil changes simply because thats what they were taught. I also know some people who run about 8000 miles between oil changes. The biggest factor is whether you do more in town driving or highway driving, and how quickly you accumulate mileage.

[CHollman82]

6-8000 on mobile 1 synthetic, but I don't judge it by mileage, I look at and smell the oil on the dip stick. I know what fresh synthetic oil should look and smell like, and I likewise know when it is time to be changed, this typically works out to somewhere between 5-10k miles depending on driving habits, season, etc. in my cars.

[peva]

Chrysler started out with I think a 7500 mile oil change interval on the 2.7, but they shortened that in later years - and for good reason.

Not all things over the last few years have been improvements in oil. They now leave out an extreme-pressure additive that used to be in the oil. I guess it's why most if not all cars now have roller cam followers - regular sliding cams wouldn't hold up with oil without that additive. You might find this interesting (originally posted here: http://300mclub.org/forums/viewtopic...24576&start=15 - scroll down to post by Krautmaster):

Camshaft wear on older flat tappet cams (like the one in my 1968 Chrysler 383) is a serious problem due to the lack of high pressure additives in the oil. Back in the old days (pre 1989) engine oil had lots of this additive (ZDDP), but the EPA found that it clogged up the catalytic converters over time. Manufacturers switched over to "roller'' cam engine designs that don't require as much of the high pressure additive when the EPA mandated that the level of ZDDP be dropped. The amount of it in engine oil has gradually been decreased to the point that you can't use modern oil in an older flat tappet cam engine without destroying the camshaft and lifters -sometimes in as little as 100 miles!(we have to use diesel oil and a ZDDP additive in the old engines to keep them alive) What we are now finding out is that 6-10 year old cars with roller cams that have been run on this new low ZDDP level oil their whole lives are wearing out the camshafts too. Even the brand new car in your driveway will have the same problem in 75,000-100,000 miles, maybe less as the amount of ZDDP in the oil is being decreased yet again. The only solution (after you get new cams) is to add some ZDDP back into your oil-you can buy it for about $10 a bottle, and it needs to be added every oil change.

This is one reason I chose Shell Rotella T6 when I recently decided to go to a different oil in my cars. Screw the EPA.

[micholob]

Good info ^

[ncfrc]

Look at the new Redline ZDDP additive , one 16oz. bottle treats up to 12 qts.
I was in the oil business for many years and it's not their fault as their being told
by the EPA as to what can or can not be put in Automotive motor oil.
I don't want to sway this thread towards an additive debate but some out there
only boost the Zinc side, where you need both the Zinc and Phosphorus.

A final comment on the original topic ,,, buy the cheapest gas you can find and buy
the most expensive motor oil that you can afford. Just remember if you ask 10 different
Mechanic's / Technition's about oils and change intervals , you'll get 10 different answers.

[RKBAGUY]

We're from the government, and we're here to help.

[ncfrc]

Funny , ha ha

My thoughts of the EPA

[GTXKen]

I also run Rotella and in my 70 Plymouth I run ZDDP additive as well. The muscle car forums have been bitching about oil quality for years because most of those guys run flat tappet cams. I didn't realize that the lask of ZDDP was hard on roller cams too. I have read that synthetic oil eliminates the need for the ZDDP as well.

Additive I run

[RKBAGUY]

Have you heard any of your colleagues on those muscle car forums talk about Militech-1 at all? I've used it successfully in my '99ES which now has 252,000 miles on it. While I don't pretend to suggest that mileage is attributable to the Militech alone, it surely does make one pause and think. I use the conditioner on my firearms, and it certainly doesn't seem to hurt my motor, either.

[ncfrc]

The additive you run is fine. Shell Rotella 5w40 is a very good product. Synthetic oils
have a higher film strength but not enough to protect you 1970 by itself.
The lack of ZDDP with cause slightly higher wear rates in any engine , just ones with
roller rockers , ect will usually last much longer , at least past the manufacturers warranty.
The flat lifter / cam set up is by far the highest extreme pressure point of an older engine and thats why you hear all the bitching. Oils that seem to get overlooked but are excellent in quality are Motorcycle labeled oils. Truely great products with twice the ZDDP of todays automotive oils. Most just won't buy it because it has a motorcycle on the label. These oils are designed to lubricate a 4 stroke at 12-14,000 rpms. Several popular oil manufacturers have them available in a 10w40 or a 20w50.

[gravely_todd]

I bought my 02 Intrepid in January 2003 with just under 20k miles, and started a 3000 mile oil change regiment. IMO, it is a small price to pay for peace of mind and I don't care what the manual says. I also use either a Hastings (Baldwin) or a CarQuest (WIX) filter every time and fill the filter completely before installing on the car. I use only Pennzoil high mileage (copper bottle) 10w-30 oil and have for the past 120k miles or so and have not had any problems. I put about 3000 miles on about every 6 weeks commuting back and forth to work and it also gives me an opportunity to look other things over while under the car and under the hood. Call it overkill if you want, but it works for me and I have turned over 207k miles with no oil related engine problems.

Todd

[EagleESI]

Slight interesting read on OIl and ZDDP from people who deal with oil every day.

http://www.blackstone-labs.com/Newsl...ber-1-2010.php