Rotella Oil

[30-9]

Hi all

I recall reading on here that Rotella 15 40 was a good oil for our flatheads.

So I was in the auto store today and went over to the Oil area and picked up a bottle. It read it's for diesel motors.

So did I mis-read the post or is Rotella 15 40 diesel oil good in a flatty?

[Alaska Jim]

In my opinion, no. you did not misread. I use it in My '51 Merc. with a flathead, I also use it in my '30 coupe with a Y-block. it is a very good oil.

[Seth Swoboda]

Rotella 15w-40 is used in diesel engines and your flathead V8 gasoline engine.

[zzlegend]

Use it both my flatheads and model a. Good choice.

[Bruce in southern OH]

Use in my cars, long talks on here about Zinc or lack of Zinc. Search the Forum and you decide.

[30-9]

Sponsored Links (Register now to hide all advertisements)

Excellent thanks Gentelmen!!!

[Ralph Moore]

We use it in all our fleet maintenance of semi's.

[JonC]

It's made by Shell, and I use it in my Flatheads and Indian motocycle.

[42guy]

I have been using it my flathead for 12 years.

[Ford Freak]

I've used it in various V8 engines up to 1972 . No problems ....

[CA Victoria]

As stated, lots of info already posted. I found this interesting too.
http://speedtalk.com/forum/viewtopic.php?f=1&t=35836

[Marv]

I do not know this positively, but i was told by a mechanic years ago that you could use diesel motor oil in a gasoline engine but you could not use gasoline engine oil in a diesel.

[36coupe]

I use it in my old stuff and high mileage late model stuff

[ronford]

I use Rotella oil in my 1940 Coupe per the recommendation of a local flathead specialist.
This week I carried my 1966 Mustang with 289 to Ford Dealer for free oil change that I won as a prize in a recent Mustang Car Show. The dealer recommended Rotella 15W/40
for my car. I agreed. Will see how it performs in the Mustang.

[paul2748]

I use Rotella T 15/40 in both of my YBlocks. One has gone from coast to coast twice. No problems. I wish I could say the same for the rear main seal.

ZDDP right up there.

[LazarusLong]

Guys,a word of caution here about using a modern high detergent oil in older engines that were designed to use non-detergent oil. Namely,DO NOT use high-detergent oil in a older engine that has has ran non-detergent oil all it's life and has never been rebuilt. If you do,it will bust loose all the sludge and clog up your filter and your oil passages. The result will be your oil pressure will drop to zero. If you are lucky,you will notice this before bad things happen and will stop the engine,drain it,remove and replace the oil filter,fill the engine with 30 or 40 wt non-detergent oil,and then run it for a while at home until you see the oil pressure start to drop again,and then replace the oil filter again and add a quart of non-detergent 30 or 40 wt oil. Repeat as necessary.

By all means use it if you have a engine that has been hot tanked and rebuilt. It's much better oil.

[JT FORD]

I wouldn't put non detergent oil in any motor........

[LazarusLong]

Originally Posted by JT FORD

I wouldn't put non detergent oil in any motor........

Why? You do know the engine in your 51 was designed to use non-detergent oil,and that as long as you change it on a regular basis,there is no problem doing this,right?

Your oil system is designed to NOT keep trash in suspension,but to allow it to settle in the base so it drains out when you change the oil. Your oil filter was an option,and it was designed to catch the bigger parts.

Modern systems that use hydraulic lifters needed a different oil system where the filter trapped any solid contaminants in the oil in suspension so the filter traps them.

HD oil works fine in a clean older engine that is well maintained,but if you try to run it in one all sludged up,ugly things will happen.

I bought a 57 Ford 645 tractor from a guy once that sold it to buy one of those new tiny things that looks like a toy and has tracks. Said the tractor didn't do the job,and that's why he was selling it. I ran it around his yard long enough to get it warm,and it was holding 40 psi oil pressure at idle and not smoking,so I bought it.

I used it at home to run a bush hog maybe 2 hours a month and to occasionally move a car or a motor around,so it took a while for the real reason he sold it to show up. It started to gradually lose oil pressure,and dropped down to around 5 psi at idle. I figured he had STP'd it to death,and figured I would going to need a crank kit to fix it. Since I needed it right them I figured I would try a oil and filter change to see if I could get by for the time being,and was shocked when I screwed the oil filter off of the block and it felt like it was full of lead. I immediately went to the NAPA store and bought a couple of spin-on filters for it and a case of 30 wt non-detergent oil,and changed it out. Oil pressure jumped right back up to 50 psi at idle warmed up.

I used it that way for a few hours and the oil pressure started to drop again,so this time I just changed the filter and added 1 qt of non-detergent oil. Oil pressure jumped right back up to 50 psi and I haven't had any problems with it since.

IF I ever drop the base pan and pull the rocker cover off I may clean the oil pickup screen,base pan,and valve cover,and then fill it with HD oil,but not until them.

Evidently the guy I bought it from changed the oil right after he bought it,and filled it with HD oil. Then the oil pressure dropped drastically on him like it did with me,so he panicked and changed the oil and filter again and put it up for sale.

This problem is worse if the previous owners used Quaker State or some other parrafin-based oil in the engine. I took off valve covers on several OHV engines when I was a kid working at a gas station/garage in the late 50's that had valves ticking,and could barely see the rocker arms for all the sludge build-up. Every time I asked the owner what oil he used,it was Quaker State.

[51 MERC-CT]

Originally Posted by LazarusLong

Why? You do know the engine in your 51 was designed to use non-detergent oil,and that as long as you change it on a regular basis,there is no problem doing this,right?

Your oil system is designed to NOT keep trash in suspension,but to allow it to settle in the base so it drains out when you change the oil. Your oil filter was an option,and it was designed to catch the bigger parts.

My '51 was not designed for any particular oil but had to use the only thing that was available at the time, (non- detergent).
It was changed to detergent oil only at about 72k miles and after a few
short term oil and filter changes it has used nothing but detergent oil until now at 112K miles. The engine has never been overhauled.
The oil filter is not an option but is standard equipment on my and all other 51's.

[LazarusLong]

Originally Posted by 51 MERC-CT

My '51 was not designed for any particular oil but had to use the only thing that was available at the time, (non- detergent).

Isn't that another way of saying it was designed to be used with non-detergent oil?