I used Castrol 20/50 for years in my engines, tryed Amsoil, no differance.
I still use the same amount of oil per 50 hours as before, same fuel Economy as before. What a rip off in my eyes. Back to regular oil again. I change it way to much to pay the price differance. Blaster

To each his own. If ever you blow a head gasket and get water mixed in with your oil, you might appreciate a higher quality synthetic oil. Your oil of choice is a good oil. Synthetics do offer certain differences though. Maybe they don't apply to you.

I used to use Valvoline Racing 40# but the price was grtting high at 2.75 a quart and nobody stocked enough to do an oil change (20 quarts). So I changed to Mobil 1 15w-50. Any Walmart stocks it and it offers better protection according to in depth research by member Hydrocruiser. 4.00 a quart.

I'm not a big believer in if it costs more it's gotta be better. If you're changing your oil frequently, and checking your levels frequently, a blown head gasket would be caught early on anyway. Now i do believe in the proper weight oil. I like synthetics or at least blends, in my outdrive becuase of it's resistance to heat breakdown. If you find yourself not changing engine oil very frequently, then synthetics are best for you becuase they last longer than the organic oils.

Just what exactly did you expect??????

A 5mph gain???? You expected it to use less oil???? That has very little with the oil. It depends more on the condition of the engine.


BTW, I don't even use Amsoil.

I do use Amsoil but the reason to use syntetics is for the protection not for the mph you think you are going to gain. People say that changing the oil frequently is the key, to a degree yes but what happens when your motor starts overtheating? oil temps starts going up and no matter if you changed your oil the day before is gonna start breaking down, i would rather have syntetic and have the extra time before i realize i have a problem to shut it off before it blows.
jus my opinion

i agree,i use amsoil for the extra protection,and piece of mind ,been using it for years in everything and never had a problem in fact everything i tore down that had it in it looked brand new.

I use Amsoil and am a believer in the fact that it provides the best protection in a high stress load application. Bear in mind that if you run your engine hard, you can get regular oil hot enought to the point of breakdown. Amsoil will hold thru the hard runs and provide the engine protection needed. The series 2000 oil is a small price to pay for increased engine life.

Castrol and Kendall 20W-50 are two excellent products. They do hold viscosity well and shear well too. Any PAO synthetic oil will protect bearings better at high temperatures.

If you want fuel economy as well use an API SL rated synthetic oil like
Mobil-1 15W-50.

With synthetic oils it's not so much what you see as what you may not see!
If you like Castrol GTX stick with it as it is very good.

As far as Amsoil is concerned it's best Series 2000 and 3000 they are in the same ball park as Mobil-1 20W-50 and Redline 20w-50 or 20W-60.

If you likie the Amsoil usie the Amsoil.

I likie the Mobil-1 V-twin 20W-50

Blaster,

You have two conflicting issues. High oil viscosity will reduce oil consumption. Low oil viscosity will improve fuel economy.

You can't have it both ways, although multi-viscosity oils help with this compromise. Unfortunately, they are blended with low viscosity base stocks, which increases engine wear.

Michael