I have a 00 x with the v-10. I been running 5w30 since I got it in the mobile 1 fully synthetic. I could not find the 5w-20 in a fully syn, so I just stayed with Mobile 1 5-30. I live in RI and have never had a problem...what is the difference between the 2 oils? these numbers on the oil are like reading latin to me. I heard that 5-30 and 5-20 are so close it really doesnt make a differnece. I do some towing in the summer and the temp does not go below -10 f in the winter and thats extreme. in the summer it can get in higher 90s and has hit 100 last summer. but I am just at odds over these oils. what the heck is the difference in real world terms? my X has 74285 miles on it. New engine at 25000 miles. After that I vowed to always run the synthetic and i been running the mobile 1 on the new engine since the first oil change which I did at about 27000. This engine runs like a top, like a normal v-10 would. I was brought up on 10w-30, and my neighbor said I should run 10-30 because ford uses such a thin oil to get better gas milage but it sacrafices engine life. I cant really see ford doing such a thing, but I used 10-30 in all my cars except this X. It is all foriegn to me. I would appreciate some knowledge, infact I would love it.

 

Welcome to the Oil and Lubrication board. If you read down thru the last several years of threads you will see lots of thick-vs-thin debate. the "W" number is a maximum cold cranking simulator test viscosity at different sub-zero temperatures. The higher number is the viscosity at the boiling point of water. There is no absolute agreement here. The following is my opinion only.

5w-20 Motorcraft (or Conoco, 76 or Phillips, the same thing) synthetic blend has perfromed very well in Ford modular engines. However, Ford did not specify 5W-20 for any other reason than gas mileage, period. In 100 degree summers and towing, I still favor a good 10W-30, like Chevron Supreme. Since you are running synthetic, 5W-30 should be good all year in your climate. Also, some V-10's are known to consume a lot of oil. If that is a problem with 5W-20, you might want to go up a bit in viscosity.

Jim

 

MY opinion, and it's probably worth what it cost you, I believe that a good 10W30 is the best all-around oil on the market.
I favor the Chevron Supreme or the Havoline 10W30 conventional oils.
Personally, I have yet to be convinced of the real, tangible benefits of synthetics for most regular applications.
I now have 160,000 miles on my 4.2 (2000) model.
5w30 is Ford's recommended oil. I have always used 10W30.
The engine runs fine and shows no signs of comprimised longevity.

Like Jim, I hold the belief that 5W20 is all about CAFE numbers and not building the best oil, with mpg being a secondary concern. If you read the numbers for EPA requirements for avg. fuel savings afforded by 5W20, I seem to remember that they are not (in my opinion) significant.

Even though I have read Flash's comments regarding the robust 5W20 oils, and that is what I will run in my 2005 4.2 until warranty expires, I tend towards going back to 10W30 in it after the warranty expires.

My personal experiences with the afore mentioned oils have been outstanding. I'm a believer in the "If it ain't broke, don't fix it." philosophy.

Old habits die hard.

 

I agree with what both Brian and Jim are saying, but I thought that I should point something out. They are in California and Alabama. Niether one of them are in an Arctic climate. You do not indicate where you are located. If you are in Canada or Alaska, for example, use the thinner oil in the Winter time.

Good luck,
Doc

 

http://www.baileycar.com/oil_overview_html.htm

http://www.nordicgroup.us/oil.htm

If you want to learn a little about oil, I'd suggest checking these sites out. I'm pretty sure it's on one of these sites, but I'll mention it anyway... Winter starts merit the use of a 5W oil. It runs through it faster. And the bearings are what would determine (largely) a good oil weight for a particular vehicle. When bearing clearances are larger, like in an older engine, it might be a good idea (my parents do it) to switch to 10W-30. It's usually my opinion that it's best to stick to whatever the manufacturer recommends, but you're not going to break anything with 10W-30. If you ever feel like more knowledge.. ... Google it. That's usually what I do. Comes up with all sorts of neat info.

 

First things first. The Mobil One you have been using is gone. M/E has reformulated their entire line. The replacement for the M1 will be the 15,000EP oil and it is not the same. The old M1 would shear back to a 20w as it was barely a 30w anyway. So, nothing hurt here. But, now you are up against having to select a different oil for your truck. You will find that the oil speced for your truck is a 153-H oil. It meets standards that most common oils can't touch, especially in the allowable deposits, viscosity change, oxidation, etc. I have posted the criteria here if you want to search for 153-H. But the 153-H spec has been superceded by the 930-A spec which is a little different but lets just describe it as near bulletproof. It comes in the Xw-20 oils only. Luckily for you, there is also the newer 929 speced oils that are in the xw-30 viscosity range. If I had your rig with the mileage that it has, I would be looking for a 10w-30, 929 speced oil. The reason, your engine has been running a slightly thicker oil than the xw-20 oils and the bearings are broke in for that viscosity. To go to a lighter oil at this point would most likely result in lower oil pressure at the bearings and accelerated wear at the bearings and rings. Because the newer speced oils are at minimum, a synthetic blend, and unless you have winter temps below -40 degrees, there is no reason to run the 5w-30, just run the 10w-30 year round. The 10w-30 Mobil oils will have a better flashpoint, higher TBN, less subject to sludge, oxidation, etc. If you select an oil outside of the Mobil lineup, just look for the spec on the back of the bottle. Any oil meeting these new specs is darn good oil regardless of price.

FWIW, we generally see more oil useage with the V10 engine when the oil is a PAO basestock like M1. If you have some oil useage, might consider using a more common blend that meets spec. It may just use less oil and save some bucks buying it as the blends are cheaper and generally produce lower wear metals.

 

Sorry, read your post for the 3rd time and thought I would pipe in again..I understand that the 5-20 is lighter or thinner then the 5-30 now. The cold start up is the same being the "5" but the 20 is thinner then the 30. I would not go to a thinner oil, I bought the new M1 15000 mile stuff in the 5-30. I live in RI, and the temps dont go down to -40 but they do get cold. -10 to -18 i think. I love the synthetic oil, because I have seen some difference in performace of my truck between the regular oil and the m1 when I made the change the first time. I would never go to a thinner oil. If anything I would stay the same 5-30 for the start up protection, being I guess the thinner the oil the faster it gets to the top and falls on the parts. WOuldnt the 10-30 be thicker at cold start temp? and the same at operating temp as the mobile 1 15000ep 5-30? Why would I want to move up to the 10-30 What do you mean the newer oils are speced at the minimum? My truck has 74,300 on it but had a complete new engine at 25,000. Is the mobile 1 15000ep speced to a 929 oil as you say that that spec is a good one for my rig? Or does the new mobile one supass those specs? I also chose mobile one because it has a higher flash point then regular oil. U said a common blend would be cheaper and produce less wear metals...what is a common blend? is it a non synthetic oil like just regular off the shelf normal oil? I thought the mobile 1 synthetic oil provided superior lubrication thus reducing engine wear...That is why I choose Mobile 1...you just have me a bit more confused. I did plan on changing over to the new M1 this weekend like I said but, I would still change my oil every 3 to 5000. Workin on a farm in my younger years I saw the differnce oil changes can make.

 

Flash,
As always, you bring good info to the game. Thanks!
A few questions:

a) I looked at Chevron's and Havoline's web sites but did not see where any of their oils are 929 or 930 rated. Do you know the skinny on this? Have their web sites not been upadated or do they not offer any products meeting the criteria. I did look at conventional, blend and full synthetic but found none rated 929 or 930.

b) I thought the Havoline 10W30 SL (and maybe SJ) met 153-H spec but don't see that mentioned either. Am I mistaken on this? I could look on a bottle when I get home, but would have thought I would see mention of it in the tech data for the oils on the home web page.

c) Do you think the SJ 10W30 oil is better or worse than the SL? I know this has been discussed before somewhere (???) but just looking for some quick comments.

Thanks!

 

Brian,
The website is dated. Chevron and Havoline oils are certified per their respective viscosity.

No Xw-30 oil will met the 153-H spec as it is too thick

For what engine? New engine-no( like a Triton). Old engine -yes (like a 385 or FE). It's all about the add pack content.

 

I am thinkin I will jsut stay with what my engine knows...5-30 but now the quesiton is what mobile one to use....still have some of the old stuff...

 

Bananarama,

I think you are okay with 5W30 in RI because it is still 5 weight at low temperature. If you were saying 10W30 or even 10W20 if there is such a thing, then I would say you were running oil too heavy for your climate, but I think 5W30 is okay.

As a side note, if you would fill in the location area in your profile, it would make it much easier for folks to know where you are from.

Hope this helps,
Doc

 

This has been an intense topic on several forums. Go over to www.bobistheoilguy.com where there are several quite learned folks, with practical experience, engineering and chemistry background, etc.

 

I have always run 5-20,but i am thinking about making the switch to 5-30.

 

Very interesting post. It opens up a whole set of questions regarding oil pressure vs viscosity.

For example (all pressures hot at 2000 rpm, which spec is 40-60 psi), my truck (signature below) was getting 35 psi on 5w30 so I went to 10w40 and got 44 psi. After a couple years and two treatments and rinses from Auto Rx I installed some 10w30 and found the pressure running about 42. Presumably the pump relief was clogged partly open and the Auto Rx must have cured that. So now I am at another crossroads that I should abandon 10w40 and go back to 10w30. I have no idea what the truck ran before 60,000 miles as it was used. Anyway, a UOA on the 10w30 should warn me if the thing is better suited to thicker oil, but I doubt it.

Also appreciate your comment on not needing 5wXX until very cold weather (blend at minimum though). I always felt the 10wXX provides a more robust oil through a thicker base oil in the overall mix. You can even boost that by running say 4 qts Maxlife 10w30 with one qt Maxlife straight 30 (two straight 30s in the mix probably nets you a 15w30 ).

 

I would not worry about 35PSI oil pressure. Although oil pressure is a good indication of bearing condition, this indication is as compared to a new engine. As long as there is enough pressure to indicate that the oil is circulating through the bearings, you are okay. In fact Cummins, the builder of some of the best engines in the world IMHO, actually regulates oil pressure to 15PSI. They do this because they say that running oil pressure any higher than that simply wastes fuel to turn the oil pump. Their engines are known for achieving very high mileage life.

I have been skeptical of running such light oil, but after several months of study here, on some other sites and reading Sean Hylands excellent 4.6 Engine book I now feel that I understand why these engines work well with lighter oil, although living in Texas, I won't be using 5W20 rather I will use 5W30 year round. Some of the differences in the 4.6 and earlier engines that warrant the thin oil are as follows:

o These engines have roller cam followers. By eliminating the massive friction loads of a flat tappet cam against lifter, the biggest need for heavy weight oil is gone.

o The hydraulic slack adjusters in these engines have a bleed hole that is calibrated for 5W20 to 5W30 oil.

o Due to the use of hyperuetectic pistons, the piston to cylinder clearance is VERY tight. They also utilize a low tension ring package. A thinner oil is called for and can be used without making its way past the ring/piston package.


I have read some writings on this forum and others indicating that the drain back holes are too small to allow heavy oil to make its way back to the pan. I think that this is a red herring. If it is true, and I have my doubts, it is overshadowed by the reasons above.

I have used 15W40 Delo in most everything on my place for something on the order of 18 years. There are many vehicles and machinery that will continue to get it, but not my 4.6.

Have a great day,
Doc