M1 15w50 too much for a 1984 Ford 302?

[Threeofnine]

I have a 1984 Ford LTD police interceptor with the 5.0 H.O 302 engine. The car is basically a 4 door Mustang. I tend to drive it pretty hard, I just drove about 6 miles with the pedal held to the floor. The engine naturally generates a lot of heat, would M1 15w50 be too heavy for this engine? I’m using M1 10w40 currently.

 

[Analog-1]

Might be ok if there are only warm starts. 15/50 is to heavy for this engine in the stock form. Not sure where you live but one very cold winter start this oil will not flow.

 

[Threeofnine]

Might be ok if there are only warm starts. 15/50 is to heavy for this engine in the stock form. Not sure where you live but one very cold winter start this oil will not flow.

I’m in Alabama. Maybe Royal Purple 10w40 would be a better choice?

 

[wlk]

No it would be fine

 

[ripcord]

For a daily driver in a warm climate, 10w-40 is great.

 

[Analog-1]

I’m in Alabama. Maybe Royal Purple 10w40 would be a better choice?

I honestly think this is a better choice.

 

[Cujet]

The 15W-50 will work just fine. It is not unusually viscous in cold conditions. I use it regularly here in S. FL. as it is hot here year round. You could also choose something like M1, 10W-40 High Mileage oil?

As you know, these are pushrod engines, with flat tappets. So they are likely to hold up longer with a more robust oil.

 

[DuckRyder]

M1 0/40 is the standard answer.

I personally think 15/50 is too much unless it is worn out.

 

[Threeofnine]

The 15W-50 will work just fine. It is not unusually viscous in cold conditions. I use it regularly here in S. FL. as it is hot here year round. You could also choose something like M1, 10W-40 High Mileage oil?

As you know, these are pushrod engines, with flat tappets. So they are likely to hold up longer with a more robust oil.

Wait, these are flat tappet motors? I though they were rollar.

 

[wpod]

The 15W-50 will be fine let the oil warm up a bit before WOT. See How the oil feels. It will not hurt anything . The issue would be the start up temps in the winter .

 

[Accent Abuser]

The 15W-50 will work just fine. It is not unusually viscous in cold conditions. I use it regularly here in S. FL. as it is hot here year round. You could also choose something like M1, 10W-40 High Mileage oil?

As you know, these are pushrod engines, with flat tappets. So they are likely to hold up longer with a more robust oil.

I regularly use it up here in the Northeast. I've put some in my freezer which is set to -20°F and it still flows easily. I definitely wouldn't be doing regular cold starts in the 20 and teens with it but anything above freezing is fine.

 

[Cujet]

Wait, these are flat tappet motors? I though they were rollar.

I was simply going by memory. I "think" the Ford 302/5.0 in 1984 was still a flat tappet engine.

Google says the Mustang got the roller cam in 1985. The trucks a bit later on. But reading some more, it does seem that some full sized Ford's did get the roller 5.0 in 1984.

 

[eljefino]

MI State police test cruisers before they buy them, and publish the results so others don't have to repeat the efforts. Anyway they do a test on a track where they mat the pedal for 20 minutes and see if anything blows up. So long as your Vic still has all the oil coolers and whatnot and it's in decent shape you don't need a 50 weight, and 40 is already a grade over stock. Overly thick oil takes too long to go through the engine, and transfers heat more slowly than the proper stuff.

Temp and pressure gauges might provide some reassurance.

 

[Plumb Bob]

I would run Delvac / Delo / Rotella 15W-40 and be happy with it.

 

[DuckRyder]

It is CFI right (throttle body)?

I'm nearly, but not entirely positive is a flat tappet. If you can find the new home of the old emergency vehicles owner operator yahoo group those guys would probably know more for sure.

 

[Oldswagon]

I beleive he is talking about the fox body Ford LTD, not the Panther body LTD Crown-Victoria. The police Fox LTDs used a 302 HO but it was not the same as the Mustang 4bbl or MPFI 5.0 HO. That said they would out run a 351 powered LTD Crown Vic. As mentioned above it was a CFI engine and in the LTD it was rated at 165 hp. It would also have a flat tappet cam.

If it were mine, I'd stick with the 10W40 or go to 0W40 FS unless severely worn or has very low oil pressure.

 

[OVERKILL]

I'd use M1 FS 0W-40 in it, that's my standard answer for Windsors at much higher power levels than that unit is making. The 15W-50 just risks licorice sticking the oil pump drive shaft and hurting the distributor gear for no benefit, the Windsor engines have excellent lubrication systems, they don't need bandaides.

 

[Dave Hess]

I like 10w30 Rotella T5.

 

[Cujet]

I'd use M1 FS 0W-40 in it, that's my standard answer for Windsors at much higher power levels than that unit is making. The 15W-50 just risks licorice sticking the oil pump drive shaft and hurting the distributor gear for no benefit, the Windsor engines have excellent lubrication systems, they don't need bandaides.

I had forgotten about the Ford distributor/oil pump drive. It is always a concern, thanks for bringing that up. The M1 15W-50 is not unusually viscous when cold, and will not excessively load the drive, as it does have superb cold weather performance. Especially when compared to say, Valvoline 20W-50 conventional or similar. These higher viscosity bulk oils have a favorite of some Florida police departments for decades.

 

[Threeofnine]

Related question. Last oil change I filled the car with M1 10w40 high mileage. Before that I ran Valvoline Maxlife synthetic blend 10w40. The car seems to be using a lot of oil with M1. I’ve driven around 500-600 miles since the last oil change and have already used a qt of oil. I used a qt probably the entire interval when running Maxlife. Is it possible this old engine does not handle synthetics well? The reason I ask is because classic Ferrari is another hobby of mine and my mechanic told me to always use conventional in any Ferrari older than 1984. He said the style of rings they used didn’t seal well and synthetic oil would lead to excessive oil consumption. Maybe this is what’s happening here?