Hydrocruiser

Sounds great!

I am interested to know your experience with Mobil-1 gear lube as some members have used it with much success.

ActiveFun

Hydro,
If you mix in straight 40, does it have to be Mobil 1 synthetic? Here is the question. Is it better to mix in a lighter weight synthetic than the same or close weight non-synthetic?

minxguy

Are you asking ....if I am runnig Mobil 1 (or another synthetic brand) and I need to add oil should I add an oil with the same viscosity that I have in my engine? Mobil 1 does not make an SAE 40. You can add anything you want. First rule..any oil is better than no oil. Modern day petroluem oil will mix with Mobil 1. You should try to use an oil with a viscosity equal to whats in the engine. Adding a thinner viscosity oil will have a greater effect on the oil in the engine ( % of change in viscosity to the light side) than adding a heavier oil. If you are running a 10-40 and you add 10-30, the 10-30 will change the final viscosity more than if you added 20-50. I would hope that nobody uses a 10-40.in a boat motor. I was using the viscosity for the sake of th example. Ken

Hydrocruiser

From the little I know about "mixing" and producing a synthetic blend..my understanding is that usually a straight weight conventional is the base that the synthetic is added to..why I don't know.

If I were to play with Mobil-1 20W-50 V-twin and add a conventional product in a 50/50 mix I would use 40wt Kendall.
Same with the 15W-50 M-1. Something "inbetween" as the base in viscosity...not the "max".

I do not exactly know what you will wind up with but I would bet it would be a good blend and perform well.

...so when ya gonna do it?

Hydrocruiser

Okay guys...Mobil-1 15W-50 is no longer being offered by Wallyland at this time in quarts or bulk containers...'cept for the leftover stuff..why? .. who knows.

They do now carry Castrol Syntec Fully Synthetic Oil in the 20W-50 weight...black bottles.... darn good stuff and it specs out with the best 20W-50 synthetics as well.

Price...$5.56/qt in quart bottles only.

Great stuff...great price...

o2man98

The problem is if it is like the other Castrol Syntec oils it is mostly GRP III thus not a true "Full Synthetic".

minxguy

At a retail of $5.56 I highly doubt that it can be anything else. A full PAO or Ester formulation would be at least 50% more. Ken

ActiveFun

Thats a good price. I just was in Monticello last weekend and found the 15W-50 in quarts for $6.20. They had the 10W-30 in 5 quart containers for a lot cheaper but I went with the 15W-50. I bought all they had which was 3 - 6 quart boxes.

Hydro, If my motor has always had the Mobil 1 15w-50, is it ok to switch to the Castrol?

Hydrocruiser

It is a Group III hydrocracked product.. it was a Group IV in 1997 before they reformulated it.

...however...the isomerization process they use makes it about as tough as many Group IV bases as seen in comparison to conventional oils and synthetics.

As we know there are many grades of Group IV bases. Amsoil has several for many viscosities and some border on Group III...while the Series 2000 and 3000 products border on Group V formulations.

FYI...the recent reformulation of V-Twin shows it is a Group IV with no ester Group V's. It still specs out the same.

The only true Group V. is Redline as far as I know...it's like $11/qt.

Why the reformulations? You tell me..

Castrol 20W-50 "synthetic"is a real good product..excellent additives...M-1 has the edge of course..

Hydrocruiser

The Castro will work fine...