Thinking about going to synthetic oil in the van

[bonneyman]

The 2004 Astrovan is starting to get up there in years though the mileage isn't comparable (only 140,000). I've been told to go to high mileage oil, but was leary about putting oil in there that will swell old seals and gaskets.
Considering switching to full synthetic oil. The summers here are brutal, and I know synth is alot better at handling the heat without breakdown or changing lubricity characteristics. Thinking about AMSOIL. New mechanic I'm going to says full synth would probably be a good idea.

What do you guys say? Good or bad? Plus it'll be a big jump in price but quality is worth it to me.

[fatfillup]

I know they used to say switch to synthetic early in a motors life or don't do it but that may very well be a myth. 

I say post a thread over at BITOG and get a pissing match going

[walrus]

I run Synthetic in every thing I own. 67 Mustang, 2019 GMC, 2015 Rav 4, 1995 GMC diesel, 1957 Ford Tractor, Generac Generator. etc

[slip knot]

I've always been of the opinion that if its working why change. Are you seeing anything that would say a change is needed? I've always run dino oil in all my machines until the new Ford came into the fleet. The newer engines seem to do better on synthetic oil so I will run it in the new one but the rest will get the cheap stuff.

I think its more important to change it regularly over what type you use. Even with the synthetic I will change at 5000 miles.

[Heiny57]

I changed the tranny and diffs fluids in the 97 mini truck that was not leaking. Now I am changing seals because it is leaking. I say go with what got you there and I like the high mileage oils in older vehicles.

Oh ya I drained the synthetic fluids and went back to regular.

[Jamesyarbrough]

save the money on that also in stuff. not that much better than what u can get at Wal-Mart for $25 a jug.  any name brand synthetic would be good. my fav is Mobil, but Pennzoil is pretty darn good as well.  make the first oil change Intervals short, like 1500 miles. then do 3k then step up to 5k. I wouldn't suggest stretching past 5k for a few oil changes. best (and most affordable) filter on the market right now is the fram ultra synthetic.  it's about $9 at walmart. all the rest of the frame are crap tho. dont run the orange can!  my next fav would be wix. but they are more expensive.

[muddy]

I have my own opinion but I'm following this to see what you guys with some more experience say.

Sent from the twisted mind of the Mudman

[Jamesyarbrough]

I changed the tranny and diffs fluids in the 97 mini truck that was not leaking. Now I am changing seals because it is leaking. I say go with what got you there and I like the high mileage oils in older vehicles.

Oh ya I drained the synthetic fluids and went back to regular.

the synthetic probably cleaned the gunk out that was  clogging the holes in those seals. most  new name brand synthetics are really just group 3 dino. not hard on seals at all. 

[bonneyman]

I wouldn't go with the long drain times that many synthetics recommend. Tucson heat and stop-and-go traffic is just too hard on things. Was just thinking if it would help lube the inner workings better do to inherent superior synth lubricating properties. Less sludge build-up, too.

Keep your opinions coming. I've got 3 months before the next scheduled oil change.

[muddy]

I wouldn't go with the long drain times that many synthetics recommend. Tucson heat and stop-and-go traffic is just too hard on things. Was just thinking if it would help lube the inner workings better do to inherent superior synth lubricating properties. Less sludge build-up, too.

Keep your opinions coming. I've got 3 months before the next scheduled oil change.

Honestly if your not going to do the longer intervals I see no point in paying for synthetic. Unless it under severe driving circumstances or long intervals, conventional oil has come a long way and is plenty good enough. If you want you can add an oil stabilizer like Lucas. MHO

Sent from the twisted mind of the Mudman

[strik9]

The old engines were loose tolerance bearings internally compared to modern engines which some are tight tolerance bearings.
About the year 2005 many cars were made to tight tolerances.   You know by the oil recommended by the maker.  Toyota Yaris, 0-5w oil, tight.  A Chevrolet six, 15-40w not tight.

Never put high mileage sludge oil in a tight tolerance engine.   It blocks oil passages by cooking to carbon and eats parts later on.  Be aware if your older car drips a bit on regular oils because changing to synthetic will clean out the sludge slowly and demonstrate every worn seal.
If not so high mileage it should change over without any problems.   
Gas mileage improves a bit as it flows better through the bearings and cleans up the passages.

If the rings or valve seals are bad it will show slight consumption of synthetic where 15-40w wouldn't be really notable.

  So don't bother with a leaky beater car but consider it for a solid engine.

Experience from working in a shop that attracted old beaters more than nicer cars.

[pep]

2004, oil changes kept up, I say you can switch without a hitch just fine. Not sure when the synthetic oil hit the markets. However purchased the 99,  synthetic has been used since 150k now.

The real key to engine wear is oil changes regularly synthetic, have no real proof I can point for a thumbs up or down.

New cars, new spec engine, synthetic the way to go. Oil life for the 99 bout 4-5 k the truck starts to complain. Get the light, oil is changed with in a week.

The HotRods, still get good old tried and true Castor oil, the new car coming will be treated to synthetic

The choice is the owner's, it all comes back to the regularity of the maintenance.
pep

[bonneyman]

I got the '04 van in 2007, a lease vehicle that the 3 year manufacturers warranty was expiring, so fleet companies choose then to trade in and get new. Had 89,000 miles on her, I assume the lease company did good maintenance.
Since then it's been oil change every 3-4,000 miles or 3 months. Uses 5w-30. I usually do the changes myself, then get lazy and have a lube change place do it - and I get instantly reminded why I do it myself.  The rear main seal was replaced 10 years ago, but still had a small leak somewhere. (Would have a few drops a week build-up in the garage). Mechanics couldn't ever find it, and I rarely saw a drop on the dipstick when checking it 2-3 times a week. Two months ago the drops got bigger, told them they had to find out where it was coming from. Long story short, found a new mechanic and they replaced the pan gasket. Problem solved.

So I figured it was now or never to switch to synth if I were going to do it. Engine runs great - miles aren't too high, might benefit from it, might not. Always willing to pay for quality, so if synth will provide a real upgrade it's worth the price. If not, I'll keep feeding her the way I've been.

[stokester]

As others have mentioned this is a topic of much discussion with no real answers.

My opinion.
- synthetic oil has better flow properties in both hot and cold conditions
- the manufacturer recommendation is important - if it says synthetic then be sure to do it
- older vehicles that have small drips will become worse with synthetic because of their properties
- Amsoil is good stuff but not worth the price nor hassle to find the dealer - Mobile 1 is generally regarded the standard

What I use...
In my  air-cooled motorcycles (dry clutch) goes Spectro motorcycle-specific oil while I use Mobile 1 in the water-cooled, also dry clutch.
My Jeep is still under warranty so it gets what FCA recommends.
My 2005 F150 gets Motorcraft semi-synthetic as recommended in the owner's manual and available at the local parts store along with a Motorcraft filter.

The most important thing is regular maintenance and I regard all the additional additives as transfer devices.  Transfers money from your pocket to theirs.