Bob you're right.

Many people switch to synthetic oil here, no matter how many miles they have, and with no ill effects. I've changed to synthetic on the 94 and 03. Both being over 100,000 miles when I switched. I didn't even think twice. I picked up 5 qts of Mobil 1 the day after I bought the 03. Already drove 3000 miles and the oil came out golden brown Saturday.

The most important thing about oil is changing it regularly. If you use conventional oil and change it when you should you'll be perfectly fine too. The 3800 is not prone to sludge build-up or other oil-related problems when changed regularly. Some prefer synthetic, some don't.

I put Mobil 1 in my car about a month ago. It has 107,500 miles on it. Runs slightly cooler now. You can get a 5 quart container of it at Wal-Mart for 20.00 bucks. I used the NAPA Gold filter. The NAPA guy said they were made by Wix.

The oil leaking is kinda odd......The myth of "If you have no leaks on a high mileage engine and switch to synthetic it'* gonna start leaking" is what it is, a myth. If you're leaking like a qt every 500 miles or something like that, then no, I wouldn't waste the money on any synthetic oil. All you're doing is paying $5/qt to spray the car and highway with it. If it'* a small leak, it won't get any worse probably, if anything, like in my case, it could possibly leak less if not at all with the switch.

If you're burning it, chances are synthetic may either slow it down or stop it, because of the higher volatility point of the oil, but no guarantees there.

I switched my Dodge Ram Cummins Diesel over at 139K to Amsoil from cheap chrysler **** dino, and I have 12K on the oil and filter now, and haven't burned a drop. Even towing from MN to Montana and back running 75 MPH for pretty much 15 hrs straight.

I also had a valve cover gasket leak which has pretty much stopped since a lil after the change. Not sure if I can contribute that to brand, none the less synthetic, but it stopped.

As for the Mobil 1 and most other "Full Synthetics", They only have to have a MINIMUM of 8% synthetic stocks in their oil to legally be called a "Full Synthetic." Why would they have to put in anymore than they have to with most oils, when they're a crude oil refiner? It costs them more to put more in when they have all the crude they could want to put in that bottle. Low production cost, higher profit margin on what'* being sold pretty much on the shelf next to it. Amsoil is 100% full synthetic, no crude.....And is brewed in Wisconsin. No dependence on overseas oils.

But also, plenty of 3800'* have hit the 300K mile mark on just dino oil from wal mart or wherever....More or less, everything is choice. You'll get more protection, and longer drain intervals from synthetic, especially Amsoil, and lowering your maintanance cost and down time, by paying a lil extra each change, by going 3X the 3K mile interval.....Or you can drain and change your filter every 3K and not have that extra protection. Most synthetics you can go 5000 plus with....Amsoil you can run 15K on severe duty and 25K normal service on one change and filter...possibly even farther with aid of oil analysis.

Ok I'm done rambling now.

I've had real good luck with synthetic oil in the past. I first started using it in a very high mileage Volvo 740 turbo that was using about a quart of oil every 1500 km. After the change it started burning about a quart every 4000 km.
since then, I use it in every car I buy. On wife'* recent 2200 mile trip the car used less than half a quart and she said it used that within the first 400 miles. I guess it found it'* level and just stayed there. Next time I change the oil, I'll just leave it half a quart down and see what happens.

If you are interested in information/discussions regarding oil and oil filters, this forum might be of interest to you. Keep in mind, as with any forum, people can post most anything they want.

http://theoildrop.server101.com/forums/ubbthreads.php

All I'm running is Castrol synthetic blend oil with an AC filter.

The only real advantage the Fram has is that it'* easier to put on.

If you don't wish to upgrade the filter, atleast use the OEM filter and purchase the AC. Afterall, it'* almost the same price as the Fram.

For a more in-depth discussion of oils, this is a good article also.

http://www.geocities.com/Yosemite/Go...motor_oils.htm

And as you may know, the forum you posted is connected to this perennial favorite oil information site:

http://bobistheoilguy.com/

As some of you have seen me post before, I'm not an oil fanatic and believe that the MOST important thing to remember about oil in your engine has nothing to do with brands, types, viscosities, or anything else more scientific than the importance of regularly changing your oil.

Certainly, you will see many studies that support the superiority of one brand, type, filter, additive, etc over some or all others, but I've seen a number of vehicles run over 400K miles using nothing more than least expensive Walmart oil and filters. BUT, the oil was changed every 3000 or so miles.

EDIT: Oh yeah...FWIW I do happen to use Mobil 1, but that'* just my choice.

Also changing it just because it'* "dirty" is just a waste of money. If you choose to run dino oil, then go the full 3K.....Just because it'* "dirty", doesn't mean the oil is shot.....it means that the oil is WORKING

Oh, no. You can't mix the two oils! They can't work together.