At what intervals do you change your oil?

Today I replied to a thread about synthetic oil and it has me thinking about switching from non-synthetic.
I now use non-synthetic Mobil which you can find at Wal-Marts under the name Super-tech for 87 cents a quart (Mobil makes it for Wal-Mart). I believe any oil that has the American Petroleum Institute Certified star burst on the font label is good for me. I only use Fram or Wix oil filters and change my oil & filter every 4000 miles.

My questions, what oil do you use?
Synthetic or non-synthetic?
At what intervals do you change your oil?
What filter do you use?

Thanks for your help.

 

penzoil non synthetic

i change my oil every 3-4K( speaking of which i am overdue

fram 16-40 filter

 

In my Dakota {318} I run Castrol GTX 10W-30, I use a Purolatur PH14670 filter, I change my oil between 4500-6500 miles. My engine has 126,000 miles on it. I have never bought into the theory that oil should be changed at the 3000 mile intervals that the oil change places tell you, I use my service manual. I do strongly believe that you should stick with what ever oil you start using, especially after about 40k miles on the motor, changing brands of oil all the time introduces different types of detergents and additives that will eventually cause oil leaks in my opinion. Running your motor at to cold of temp will also cause some of the crudding that people used to blame on quaker state oil, I know, I had several vehicles that ran it exclusively without the crudding but I also ran a 195* thermostat where in alot of the older cars, people would immediately change the thermostat to a 160* right after they bought the car, they were scared the car would overheat easily if they had a thermostat rated that high in them.

 

I change my oil around 3k. The jeep isnt driven daily, but when I do drive it, its usually for at least 3-4 hours.

Quaker state is what the PO used, and I stay with the same brand.

I bought a case (12) of the AC brand Duraguard filter which arent made anymore. It has 315 sq in of paper filter whereas the orange Fram filter has 190.

Every oil change takes 1/2 day because I check oil in diffs, trans & tcase and grease all fittings, and wash and reoil the air filter.

Here is an interesting site about oil filter tests:
http://minimopar.knizefamily.net/oilfilterstudy.html

 

personally I run 10w-30 mobil 1 synthetic and change every 6 - 7K.. I won't go into my "why syn is better" rant right now though..


BUBBA

 

Chuck, I agree with your opinion that an oil with the API should be good.

I also agree with Mike, stick with one brand as much as possible.

I try to change mine around 3000-4000. Non synthetic.

I had crudding with Q-state in High School. Now that you mention it, I think I did switch to a lower stat. Why is that?

 

Pennsylvania crude needs higher temp to stay in liquid form to drain back to pan, something about it burning before draining back if left at to low of temp to run/move in engine valley and such, kinda like grease in a frying pan, been along time since I saw the article in Hot Rod magazine, sometime back in about 1979.

 

I use Amsoil full synthetic oil and Amsoil Filters in my vehicles, Grand Cherokee, K3500, CJ, and GMC van. I will change over the Jeepster in the spring. I have gone 25,000 miles WITHOUT an oil change in my Chevy K3500 6.5 diesel. I run with a dual filter system which includs a bypass high filtration filter. I change the regular filter at 12,000 miles and the bypass filter at 25,000. I also do a sample at 12,000 miles to verify the oil is good and there are no internal problems in the engine. The engine has almost 110,000 miles on it now, it had about 30,000 when I bought it.

If you think about it, economically and environmentally it makes sense to use a synthetic. Although the full synthetic oil costs more initially you will save time and money with one oil change at 25,000 instead of 5 every 5,000. Plus now there is less waste oil to dispose of. You will have more time to 4 wheel and improve your Jeep.

 

Tell us about this sample to verify the oil is good. Do you mail it off to be tested?

 

Mike, I agree with you on not buying the 3000 mile change. I dump mine at 4000 and I believe I’m maybe wasting my money changing it too soon.

Maxx, at was a very interesting site that you supplied. I use both Fram and Wix from that study I will stick to the Wix.

If I may add to Mikes answer to Greg concerning low oil temp. If the oil temp is to low it will not allow the oil to pass through the paper filter, as Mike said “needs higher temp to stay in liquid form”.

Good info keep it coming.

 

I have herd of a test with Amsoil and it was done at 14,000 without a filter change. The one trouble with Amsoil was it’s ridiculous viscosity. They started with 5w30 and the oil had thicken out to a 15w40 by 14,000.

 

Yes, AMSOIL has the kits. It is a bottle and an informational form about your equipment, which needs to be filled out accurately. They are about $8, and you have to pay the shipping, I think last time it was $1.25, but don't quote me on that number. If you have a real problem they will contact you in a couple days by phone or fax, otherwise a report will be sent in about 2 weeks.

 

I agree with this except for the 25,000. For a 4,6,8, cyl gas engine a more realistic number for those engines would be 10,000 miles using synthetic oil. It also may depend on how much oil you add per 1000 miles. If you add 1 quart every 1000 miles you could possibly add 5000 miles onto that 10,000 total. As for your diesel you hold more oil and have two filters.

 

I use the 15W-40 in my K3500 and it has always remained at 15W-40. There must be more to the situation, (the equipment may have something wrong with it, or using bad filters) if the Viscosity changed in 14,000 miles.

 

The vehicle that was in the test was a 02 Z28 5.7L V8 with about 30,000 miles on it. They tested it at an independent lab every month for a year. Everything was fine with the engine and the only reason they stopped was because of the thicken oil. I believe engine builders spec oil for a reason and that oil was far, far thicker than intended for not to mention loss of fuel economy. Don’t get me wrong Amsoils a very good brand and if it wasn’t for the thicken oil they would of kept the test going. You did mention that the company that you bought the oil from also tested its own product, sometimes finding objective analysis data is tricky.

 

I changed all lubes in my 98 K-1500 to full synthetic, tranny, transfer case, diffs,and engine. I change the engine oil right around 7k. I'm using Mobil 1, but I have several friends who run amsoil [in everything,for years] and have only good things to say about amsoil.
The jeep has synthetic in the trany/transfercase only, the diffs and engine oil get changed to often to justify the extra cost.

 

Targetduster, just before they did the Amsoil test they tested Mobil One with good results. They ran it for 18,000 miles with an oil filter change at 12,000 before it was done.

 

Here at my job (utility company shop foreman) we change our oil every 4k. Of course our rigs idle all day long when they aren't running down the freeway. During a storm or major event I've seen differant rigs run for two or three days without shutting down except to fuel up. One crew will work for 24-36hrs then go home and another crew will jump in the rig and take off.
We just use 15-40w for the diesels and 5w-30 for the gas rigs. I buy it in bulk from our local co-op. It's nothing special and has kept our engines in really good shape considering how much idle time they see.
We used to use Wix/Napa Gold (both the same). Now we use Baldwin, which I haven't used enough to form an opinion on yet.

 

5w-30 in the jeep (sbc 350) with MMO. 5w20 in the Superduty. Change oil in the truck every 5000 mi. Jeep every 6 months. I don't drive the jeep enough to worry about the mileage.

FWIW, I run MMO in the fuel tank too

 

I run Kendall 10W30 in the colder times of the year and then 10W40 in the YJ in the summer.
The Ram, the XJ and the CJ all get Kendall 10W30 year around.
Fram filters.
Every 5k for all but the CJ.
It will be only once a year. When its moving again. It'll be a trail Jeep only.