Oil for Crusader 8.1

[buster53]

Thanks guys.

[tomschauer]

I believe we all know GM makes these engines. GM has required Mobil 1 (for warranty) on all of its high performance roller V8 motors since 1992 I believe. Mercedes Benz, also requires mobile 1 as I believe BMW also does. They all only require 12 -15k mile changes.
I have personally disassembled 2 motors with over a 100k miles on mobile 1 and found zero sludge build up. In my younger years I disassembled many motors with half the mileage that were so full of sludge you had no question why they failed. (not rottella as far as I know)
That being said, in most of our marine applications, the oil is changed long before its life is anywhere near its end, so I personally believe its more of a personal choice.
I am not knocking rottella, as I know of no negatives. I am just a fan of full synthetics, and know an R&D enginner from XOM that has show me bullet proof evidence the stuff does not break down.

[Samuel]

I don't know how old is your gas I would carry 4 fuel filters and gas to fill filter with the wrench to take fuel filter off.
I guess you have Sea Tow or Boat US I would not travel without it.

[mjk1040]

Tom to each his own. Personally can't see the added expense for oil only used for around 6 months and may be 50-100 hours a year. Our Crusaders are stickered for 40W on the fill caps. Had synthetic put in our Harley after the break in period and had it removed on the next oil change. I could hear a lot more engine and tranny clatter with the synthetic oil in the crank cases. I to have torn down engines, just did a pair of 1986 5.7l Crusaders in 2014 with 1200 hours on them and I got to tell you they were pretty clean and I didn't notice a lot of residue any where in these engines. Guess it's all a personal preference. And even though it's the norm these days and the newer engines call for it, I was never a big fan of multi viscosity oils. Guess I'm from the straight weight generation is all!

[MakinTime]

I run Brad Penn 20-50 per engine rebuilders requirement for warranty. It has a high zinc content. Not sure that is needed for a newer 8.1L. Seems to work good in my 7.4’s. I know all my friends use rotella and seem to like it. Easier and cheaper to get that’s for sure.

[bud37]

Heres an oldy...anyone remember the green coloured kendall gt1 40wt oil....now if I could find that now....ahh the good old days........

[mjk1040]

Bud, that was back when oil was oil. Not a mix of recycled and new oil sold as new oil! MT what does the Brad Penn run a quart? 3-5 Times the cost of Rotella I'll bet! But I do understand the warranty issue.

[MakinTime]

The Brad Penn is only sold by the case where I buy it, for $65 a case (12). Not to bad of a price. The oil is green, never seen such a thing until I started using it 2 years ago!

[mjk1040]

MT, that's not bad at all for racing oil, matter of fact the cheapest racing oil I've seen when I was looking for a high zinc oil after rebuilding a couple of 5.7's. Think at that time the best I could find was around $120.00 a case.

[tomschauer]

http://gmauthority.com/blog/2017/12/mob ... oil-video/

Kind of interesting video about oil.