just purchased a 2004 suburban

[paulfischer]

hello all,
had a question,(posted it on the suburban forum, but no answers yet) so I wanted to post here, since we have a wealth of knowledge here.
Just bought a 2004 suburban, with 14,000 miles on her. Wanted to switch to sythentic oil. is that a good decision? I do change oil every 3,000 miles on the lumina.
Just looking for your thoughts on synthetic oil.
And yes the Lumina will be going up for sale soon.......

Thanks
Paul

[jeffcoslacker]

Always a good decision.

[paulfischer]

is there a difference in brands??

[jeffcoslacker]

Good question. There probably is, but if it's syn, it's still superior to the best dino oil.

I like Valvoline syn, Wal-Mart has good prices on 5 qt jugs of it.

Lately I've been using Motorcraft semi-syn that AutoZone carries, it's cheap and I'm on a tight budget right now (not working). Good stuff, stays nice and clear even after 6000 miles.

[tblake]

synthetics are good, but not to argue with what the mighty jeffcoslacker says, if you keep up on the subarban oil changes like the lumina oil changes, every 3 thousand miles, it would be a total waste of money to switch to synthetic. The reason most people do switch to synthetic is so they can go longer intervals between oil changes, and also to recondition old seals in leaking motors. If you plan on going 5000 to 7,500 miles between oil changes, then go with synthetic, but if your going to change every 3 thousand, stick with valvoline 5w30. I dont want to start a fight in the forum especially with you jeff, but I myself am not a fan of synthetics, just wanted to post my opinion on it.

[jeffcoslacker]

No, you make some good points.

When the only synthetics you could buy were 5-7 bucks a quart, I agree, better to just go with dino and keep regular changes. But the full syn has come down a lot and the semi-syn blends are real low, so I've been using one or the other for some time now.

I just know you'll find resins and gook in conventional oil using motors that you don't see in ones run on synthetics.

But I wouldn't try to talk someone out of using conventional if they are good about keeping up with oil changes. That is more important than what you use, true.

[paulfischer]

thanks guys!!!! I knew i would get some great opinions. I'm still up in the air. I want the truck to last, so I'm leaning towrds the syn. I've read a lot on it, and you think I would be able to make up my mind. You guys both made some great points.

Thanks again!

Paul

[99DenaliMan]

Originally Posted by tblake

The reason most people do switch to synthetic is so they can go longer intervals between oil changes, and also to recondition old seals in leaking motors.

That's what the oil shops will have you beleive. I have seen people switch to synthetics after high miles to only have their vehicles leak very badly. Maxlife does a good job with high mileage engines.
Synthetics (man-made) are a far superior lubricant and help fight sludge build up. Often times when people use conventional from the beginning they get sludge build up around their seals that act as a sealant and your seals can dry if not driven daily causing premature hardening, the sludge "although microscpoic" is there acting as a sealer to your hardened seals, once you switch to synthetics it cleans all that minature crap out and also lubricates your dry and hardened seals causing them to crack worse and wa-la your engine starts to leak. Synthetics also tend to not drain all your oil to the oil-pan like refined oil because of their bonding characteristics and for engine's with known "knocking" when first starting the synthetic can actually cut down on some of the sound because your valves/rings/etc already have the oil there.This also prolongs engine life. I would never recommend someone switch on a high mileage engine because of previous reasons and they can cause excessive blow-by if the cylinder isn't tight (for lack of better words), but with 15,000 would recommend it. I would probably go with semi-senthetic because you have the best of both worlds. You have plenty of the bonding and anti-sludge characterisics of the synthetic with a price that's not killer. Even if you could afford full synthetic, IMHO, I would use semi-synthetic. Full synthetic is a seling point and unless your car calls for it is a complete waste of money. Also with todays clearances and the introduction of pcv systems engines oil life lasts much longer before breaking down then they did in Grandpa's or Dad's cheville. It's in no way necessary to change your oil anymore frequently than the maintaince calls for. If it calls for 5,000 miles go 5,000 miles. Doing it every 3,000 is an industry driven # used for profit. Many cars (toyota in particulaur) now can go 7,500 miles and have less oil break down than Dad's cheville did at 2,000 miles.
Valvaline makes a very good semi-synthetic. Mobil-1 also does a fantastic job. The most important thing when looking at oil is to look at the UL rating on the back. It has recently been updated and "supersedes" previous oils, even though the old stuff was suppossed to either be pulled or listed as compatible with year 04 or 05 and older it is still around quite a few places and sold. The new "superceded" oil looks identical, you just have to look at the UL rating on the back.
For my expensive vehicles I demand nothing less than Mobil-1. Everything else gets only Valvoline or mobil-1.
BTW-Nice purchase. I'm sure you will be very happy with it. I just sold my 99 Yukon yesterday and am quite bumbed out. It had 157,000 miles and drove better than the day it was driven off the lot, and looked just as good. Now even though I always told myself I would never buy a GM car, am looking to buy one. . Being a Ford guy I was looking at the new fusions, maza6's and maximas. Maybe in a few years when I can afford a fuzion or 6 - Wouldn't buy a model its first year out anyways. Then I stumbled across the ratings of the lumina. Though I'm not a fan of the styling at all, I have a child and the crappy resale and good reliability on these makes it a practical purchase. (I found a 98 with 89000 miles for $3000.) Anyhow, I know you will be very happy with the Suburban. Mine had a vortech 350 with plenty of power, but with the suburbans 454 (or what ever they put into them thesedays) is gonna rob your wallet at the station. nontheless, you are still going to love it, I did mine. Make sure you keep on all scheduled maintaince for that trans, they are very reliable and heavy duty, but the 4L80-E is no cheap rebuild if they do go bad. Good luck and enjoy.

[tblake]

very good opinions. I will stick with my conventional oil, but thats was very informative. Thankyou.