Trojan Boat Forum

what oils are people using in their older engines?

you can do a search of the site this was covered before...and you'll find lots of opinions on it,,, I use 15-40 syn-blend wolfshead oil for my merc 454's

I have used dino 15w40 in my last 5 boats no issues . I have not seen any issues in older engines (I work on them for a living ). with the low hours our boats get so why worry .

Mercury Premium 15w40 in my Mercruiser 454.

Rotella-T 15w40 in my diesels (all 4 of them)

shell rotella in my chrysler 318's

shell rotella no longer contains zddp zinc per the EPA. Newer roller engines dont need zinc,old non roller rocker engines need zinc.STP addative has zddp-zinc and is very cheap. I have been using STP in my oil on the Trojan Chrysler 360s and in my 1965 mustang. I realize that I dont put a lot of hours or miles on these engines but its very cheap. I had been using rotella until the change.

I decided to go with the Rotella-T 15w40 that I had been using. After reading up on the ZDDP zinc issue, I decided that having less zinc in the oil is not as critical for an engine with flat tappets that is already broken in and had been running high zinc oil for 30+ years with only 515 engine hours. The additives they replaced the zinc with will protect my flat tappet engine as long as I plan to own it. I change the oil every year and only put about 25 hours per year on the engines so I don't think I need to worry about it so much. If it were a truck engine in a car running 20,000 miles a year, then maybe it might be an issue. I think I will just have a few beers and find something else to worry about like why my stock portfolio is crashing or why my house value has dropped 25%.

TADTOOMUCH wrote:I decided to go with the Rotella-T 15w40 that I had been using. After reading up on the ZDDP zinc issue, I decided that having less zinc in the oil is not as critical for an engine with flat tappets that is already broken in and had been running high zinc oil for 30+ years with only 515 engine hours. The additives they replaced the zinc with will protect my flat tappet engine as long as I plan to own it. I change the oil every year and only put about 25 hours per year on the engines so I don't think I need to worry about it so much. If it were a truck engine in a car running 20,000 miles a year, then maybe it might be an issue. I think I will just have a few beers and find something else to worry about like why my stock portfolio is crashing or why my house value has dropped 25%.

BINGO !

Only 25%!! you live a great area. I'm worrying about my oil, so I won't get so sick to my stomach about the other.

I was reading the comments and I thank everyone for them. I have been looking at oil myself since it's oil change time and the info helps. thx.

I was told by a Crusader rep that 15w40 oil is not appropriate for my 1990 350's, and I should stick with the straight 40. He said the 15w40 was designed for the newer roller tappet engines, and not for the older blocks.

obeejr wrote:I was told by a Crusader rep that 15w40 oil is not appropriate for my 1990 350's, and I should stick with the straight 40. He said the 15w40 was designed for the newer roller tappet engines, and not for the older blocks.

Really ? 15w-40 came out for diesels many that are non roller engines (Incl my cummins that recc 15w-40 ) many marine engines went to 15w-40 including Crusader . Crusader recommended it on the 454 and that is a flat tappet engine not roller .

The Chrysler M440 manual calls for 15/40w or straight 30w. That's for a 1973 280hp Chrysler. I've been using Delvac 1300 15/40 desiel motor oil. I called the Exxon hotline for the zinc phosphate amount which they told me was 1100/1000 ppm.

Paul-

I know Crusader recommends 15w-40 for their newer engines- but I was told I don't have a newer engine and should stick with the straight 40w per the owners manual. The rep may have had the reasoning wrong, but the recommendation may still be correct. On the other hand, he may have been full of baloney, but I am just passing on what I was told.

Just saying they recommend it for the Flat tappet engines . Nothing wrong with using 40W , as long as your in warmer/hot climates . I would not use it in cooler climates .

BTW are you going by your book ? or what the rep says ?

From the 2003 book ( oldest I have online )
Prevailing Ambient Recommended A.P.I.
Temperature Classifi cation & Viscosity
Above 50°F SAE 15W-40 “SJ”
Below 50°F SAE 5W-30 “SJ”

Off there web site
Q : What kind of oil should I use in my Crusader engine(s)?
A: When the average temperature is above 50 degrees F., use a good quality SAE 15W-40 "SJ". Below 50, use SAE 5W-30 "SJ"