Synthetic is bad?

[Russ Merritt]

Originally posted by ILBCNU6
As a former "Amsoil" Dealer (note I said former!) synthetics do offer some advantages but never in my TR! My engine builder (ANS) said and I quote "never run Synthetics in your engine" , my tranny builder (Dave Husek) said " never run synthetic oil in this tranny", my rear end is trashed because of running Amsoil Synthetic Gear Lube in it, (growls like Howard Dean!) So do I recommend Synthetic in a Buick TR, NO, NEVER AGAIN!

Really? 2 yrs running it in ALL my stuff, not one problem.

 

[turbo nasty]

Have to agree on the dino vs. syn in the rear end. Redoing my 86 GN's rear and the new eaton posi has a tag on it that tells you not to use syn due it will hamper proper operation use dino only.

I personally think that syn's are superior in the properties/measurements of lube oils(engine and stick shift). But there are crap syn oils out there ...this is were home work comes in to play.
Do a comparison pour point, flash point, detergency, zinc content, ash content, etc.
My pockets are not deep enough to use straight syn. since my motors are higher mile units and they do get the oil dirty pretty quick from combustion contaminants. and so syn or not if it has crap in it u gotta change it.
No doubt when I rebuild em they will get broke in on straight 30 dino and then once properly broken in, then it is syn all the way.
Though with other turbo sports cars I have owned , it seems as if you have any oil consumption and sart using syn the usage increases...have noticed the same with slick 50 and duralube though????

 

[ThikStik]

Ive seen that when swithching from crude to syn that rear mains, etc start to leak. Then i started using Royal Purple and it stopped. I can swear R Purple reduced windage in my GTO.

RE: rear ends, I use mobil syn in my gn and caprice. Caprice has 220k and has a light whine. Any suggestions on not using syn? I think Ill put crude back in it. Would lie to hear more of your Amsoil experienc Ilbcnyo6. I know a rear end guy in town here , and he only uses crude.

 

[turbowidow]

the possible cause of all the leaks/ o-ring failures is probably caused by the BASE STOCK of the synthetic oil used. regular buna has a hard time handling some of the more aggressive base stocks in synthetics. seen alot of buna o-rings fail, thus the reason for buna-n, viton, silicon being used today. car oil manufactures are terrible at giving the proper info for their products to the general public. if i had the resources i would love to test these fluids to get their REAL chemical make up. i also hesitate to believe these cam manufactures with thier claims of bad oil- it's always something other than YOUR product that is at fault. in the close to twenty years since our cars where built, their has to be other cars with flawed engine designs that are not having cam failures that came from the factory with synthetic oils in use.