Picked up a great '86 Ford F-150 XL, 302 V8 with 187,000 miles. I wanted to ask what weight oil would be the best to use. I was thinking 10W40, but wanted to put it out there and see what you all think.

 

I have been running 10w40 for years, but am now finding out that 10w30 might be better. It seems the base oil for these two types of oil is 10w, and they put this magic stuff in it so the oil is 30w or 40w when hot. Some people say that less magic stuff(I think it's some sort of polymer) that is in the oil, the better the oil, so they recommend staying away from 5w30, 10w40 and 20w50 oils

 

Franklin2,

I have read articles backing what you said. Years ago, I took a class on small engine repair and received a new Briggs and Stratton engine to work on. The owners paperwork which came with the engine said that the warranty would be voided if 10W40 was used. 10w30 or 30wt was recommended. I know our truck engines are far removed from lawn mower engines, but I thought it was interesting that a well known manufacturer had problems with 10W40 being used.

 

a ford 302 can run on anything between 5w30, and 15w40 diesel engine oil. What climate are you running the engine in? Cold? warm? If cold, that 5w30 is your best bet for cold starts. I use 10w40, or 15w40 diesel engine oil all summer. Like 15w40 shell rottella T. Recomended by a lot of diesel power equipment manufactures and you can run it in your truck. I think 10w40 and 15w40 are the best durring the summer because they gave my engine the best oil pressure and all.

 

I use 15W-40 diesel oil in my 300 I6 year round.
As said before, oil quality is much more important than weight, especially in older flat tappet motors.

 

yeah, I agree because of what I learned at diesel tec school. Diesel engine oil is great stuff. So many good reasons. But, I usually get a puralator filter, or any other good oil filter as well. I have noticed some oil filters to be better than others. I wouldn't spend too much though

 

I've ran Shell Rotella T 15w40 in my 302 for a couple years now, all year round, and I've had no issues. Rotella is some good stuff!

I ran a Motorcraft filter on my last oil change, and on my next change I'll probably go with Wix. I don't use Fram, since I noticed a moderate drop in oil pressure the last time I used one.

 

Wix or motorcraft if I am buying at a parts store. Baldwin if I can get it beforehand.
fram = orange can of death. I know everyone has heard about the "rumored" fram oil filter failure, I've seen it firsthand. They will never get another penny of mine.

 

That was the older days. Now, in the days of SM rated oils, a 5W-30 has a better base oil than a 10W-30 to meet strict requirements. Just throwing that out there.

I use Rotella-T Synthetic 5W-40 in my '86 F-150 5.0 EFI. Flat tappet so I just want something with more zinc.

 

same here. The frams always give me a slight drop in oil pressure. Thats not the only reasons. When you cut open a fram, they have a paper filter element. They're not made to last. For another few$ you can get a better quality filter. Wix, motocraft, baldwin, purilator, car quest, all good filters. I've learned as well how much of a difference it can, and will make
Well, DCFORD have we been any help?

 

The drop I noticed was more than slight; with a Wix filter and Rotella 15w40 and the factory oil pressure gauge, I get about half-gauge at idle and up to 3/4-gauge on the road. With a Fram and Pennzoil 30w, I got like 1/4 gauge at idle and like half on the road. Sometimes less. And I can tell you from experience, the Rotella is like molasses if it's cold, so I think it's a pretty close comparison. lol

@ Freaksh0w If I recall, it seems alot of new vehicles are calling for 5w30 from the factory nowadays.

@ Rogue_Wulff What happens with they fail like you're saying? I've never had any part grenade on me or anything lol

 

The fram filter that I saw fail, filled the entire oiling system with mush that resembled wet toilet paper. Stands to reason, since the entire filter media is paper, and the end caps are cardboard glued into place.
Just an FYI. some 20 years ago, I hauled a load of motorcraft filters to the ford dearborn assembly plant. That load was picked up from a Wix/Dana labeled plant.

 

The big thing about modern oil is that zinc is being removed from them. Not a big deal with modern cars as they mostly have roller lifters. Zinc was what prevented the old flat-tappet cars from galling the cam surface and ultimately flattening lobes/lifters.

Try to find an oil that has a high zinc content - they're not easy to locate, or buy some additive (ZDDP+). Shell rotella (diesel oil) used to have a lot, but I think they've started cracking down on diesel oil as well.

 

Tremendous amount of help, thanks everybody. That's what I love about this site.

 

That's good to know. Thanks.


Something kinda related. I use the rotella 15-40 but i've noticed that on cold starts in the morning i get lifter tap till it warms up. not really bad but enough to make me not drive or rev it for about 5 minutes cause i don't want to blow anything. any suggestions? should i switch to a thinner oil?