...and how does he know they have synth in them? You can't tell by looking at it.

Your comment "dino oil is superior to high pressure environments" flies in the face of hundreds of independant tests. In fact, I have NEVER seen a single shred if evidence to support that. Please point me to some studies backing this up, since somehow in my years of reading on this subject, I have failed to spot a single one.

Thanks!

That's like saying that dial-up internet access is superior to broadband. Maybe in your opinion, but there's not a single fact to support that, so it falls into the belief the world is flat category.

If what you are saying is true, I am glad your "mechanic" friend is far from me and my rig.

 

I thought I remember reading that Mobil 1 synthetic in the gear boxes is not recommended. Don't remember exactly why, but people said that amsoil synthetic was ok.

That being said I have amsoil synthetics in the gear boxes and mobil 1 synthetic in the engine.

 

It seems the older a mechanic is they seem very resistant to new technology. Synthetic has been lab tested and proved to be superior. Like I said,go try to burn synthetic on a stove vs dino and go pour out both in temps under 0F and tell me dino is better.

If you change your oil at 3k then the point is moot.

 

He knows what years came with synthetics. Its not just him, its the entire dealership, and what he says, a lot of other mechanics he knows of are doing the same thing.

No studies needed. He has first hand experience. I'm not saying he's (and his co-workers)are right either, Im just giving some info that I've heard and is not more information thats been regurgitated amongst online forums.

Also, thats is the second worst analogy you have put against my argument, so stop that please.

I mean when you are getting 1-2 year old trucks coming back with blown diffs, it makes you wonder. When its never been a problem before, and then all of a sudden it is, and the only thing they've changed is the oils, then hmmph? Ever notice how many new Tacoma diffs have been destroyed? I've talked to a few, and I've seen a few over on TTORA.

Exactly, and if you're changing your oil every 3k anyways, there is no point to this discussion. You guys can use your expensive synthetic and try to get a few extra miles but its not going to save your engine.

How many millions of 22r/e's are out there with 300k+ and used Dino the entire time? Who knows, maybe there'd be more if they used synthetics.

 

Actually, while I am a big fan of similes, I tend to shy away from analogies...

I will leave it up to the reader to decide where to go with this. SC4Runner and his mechanic or:

http://www.jdpower.com/articles/article.aspx?ID=208
http://p2library.nfesc.navy.mil/P2_O...ok/6_II_4.html
http://www.answers.com/topic/synthetic-oil
http://www.firstfives.org/faq/oil/oilartcl.html
http://www.performanceoiltechnology.com/AutoIndustry'sBestKeptSecret.htm
http://www.mr2.com/TEXT/synth_oil.txt
http://www.carcraft.com/techarticles...ventional_oil/
http://searchwarp.com/swa7388.htm
http://www.mobiloil.com/USA-English/...ynthetics.aspx
http://www.allpar.com/eek/synthetic.html

...and hundreds more...

 

i dont think any of them mentioned putting full syn in the differentials... so whats the story on that??

 

I am unable to find any references that clearly seperate use in differentials. Everything seems to indicate that superior lubrication is superior lubrication, whether in an engine or a diff or a transmission.

I find many pages where manufacturers state that their synthetics are suitable for use in differentials.

I am unable to find ANY credible source that indicates that there are any specific problems with using synthetic oil in geared applications like differentials.

If synthetic oil were indeed the cause behind the sort of failure rate described by the previous poster, you would think that there would be more coverage and it would be more broadly known. Instead, it looks like a well kept secret/urban legend.

 

well, I only use syn in the engine (for now), might change it in everything else when the time comes. I change mine every 5k miles because of the Toyota Warranty.

 

I used full RedLine syntherics in my Eclipse for 8 race seasons and saw almost 400 runs down the strip and had the tranny torn down once when a new race clutch was being installed and my mechanic was quite impressed by how little wear there was on the tranny with 85k miles (50k of it was bathed in synthetic) and told me to keep using the exact same stuff.

Synthetics really came into their own in the last 15 years and are gaining more acceptance since there's tons of proof to their superiority coming out all the time.
Like I said I could use dino oil and change my oil 3-4 times a year or just once using synthetics and spend the same amount of $$. I'll take one oil change a year thank you.

 

didnt you say your mechanic buddy works at a FORD dealership?

back on topic

engine - M1
tranny - going amsoil when i get it flushed next
diffs - mobil syn
x-case - going amsoil when i get it refilled.

 

tore down a 22re with 160k, all dino. all bearing wear was still more than halfway between lower limits and new. how much better would syn really have been? is this not 'proof' of something?

goofy argument. too many variables in an engine's life to pinpoint oil as a sole culprit.

spend your money the way you want.

 

Most smart Alaskans go full synthetic all the way, and now that I'm down where its hot I'm still gonna run full synthetic.

 

I run part synthetic in both my motors due to the "higher" miles they have.
The tranny and diffs get full synthetic.

www.bobistheoilguy.com has the most accurate and unbiased oil information anywhere on the web. Check it out.

 

I am a forgiven sinner, and a proud synner. Amsoil synthetics have resided in the engine, diff, transfer case, tranny, coolant, and probably a few other places I cant think about for the last 75,000 miles.

 

I am a Synner as well. We run synthetic in all of our cars, from our '86 Jeep Cherokee and '89 Dodge RamCharger to the 4Runner and '02 Xterra.

 

I agree, maybe because it's a Ford dealership. Also, are the failures related to specific vehicles, or specific axles? Maybe there was a design change recently that is resulting in the increased failure rates. There can be multiple factors that cause failure. Simply stating that the synthetic oil is causing it sounds ludicrous, especially without independent verification, or a failure analysis.

Anyway, my Land Rover REQUIRED synthetic, and it had a list of acceptable oils. For Mobil 1, I could only use 0W-40. Anything else, voided the warranty. Some manufacturers are requiring synthetic oil, because it's superior.

I run synthetic everywhere I can. I haven't done the diff/transmission/transfer-case on my 4Runner yet, but when I do, it's getting synthetic, everywhere, even the grease gun is synthetic. I live in a desert, with lots of dust, and it's very hard on the truck. There is no reason NOT to use synthetic.

 

One thing to consider...Landrover has HORRIBLE reliability ratings. I wonder if they require that oil so that they can deny warranty coverage more easily?

Anyway, I am a believer in Synthetic for certain applications. Definately if you are running your car or truck hard. And I don't mean crawling rocks, I mean racing applications. My Cobra only got Mobil 1 and I ran it to 12K on one change with a filter swap in the middle. Great oil.

On the 4Runner and the fiance's Jetta, I use Ford Synthetic Blend. I had great results with that oil. It is half the price and I can run it for 5-6K no problems.

The biggest advantage to synthetic is the long term durability. That is it. Oh, and the fact that if you want, you can get it in 0 weight.

Most people do not realize that synthetic oil is not made of plastics or something, it is merely dino oil that has been treated a certain way that gets rid of parts of the oil that break down faster or cause break down.

 

Yes, newer Land Rovers suck. On mine, the ONLY thing that was not replaced under warranty, was the transmission. I'm not saying it's great, but it did specify synthetic. Didn't make a difference, it's favorite drink was coolant...but they are owned by Ford now...

Just to clarify, not ALL synthetic is refined dino juice. Up to and including Group III are refined dino (Mobil 1, Syntec, Pennzoil Platinum, etc.), however the more expensive synthetics are not dino based. Group IV and V are pure synthetics, but they cost more. These typically include Amsoil, Redline, Royal Purple, etc. Group V are the best basestock you can get right now I believe, but this is why they're also the most expensive.

PAO's are Group IV
Synthetic Ester's are Group V
Hydro-cracked dino is Group III

http://en.wikipedia.org/wiki/Synthetic_oil

Don't you like how hydro-cracked Group III are "synthetic" here in the US, but not elsewhere?

There is also a interesting note about synthetic blends, in that they are not more than 30% synthetic.