I have heard aloy abiut sunthetic oils.
I have a 1979 F250.About a 1.5 ago I put a new 400 in it.
I have 36000 miles on it.
I have been running 5w30 penzoil in it.
My question is would I be better off running a synthetic oil in it.
People have told me that this oil will stick more to my moving parts.Thus less wear on start ups.
If so any recomendations on what kind.Also best filter to use.
Just want the best my my truck.
Spent a 1.5 restoring it.

 

Synthetic or dino oil is kind of a religion now. You make your decisions based upon experience, lab tests, marketing hypoe and then let your religion push you to the correct side.

I have used syn since 1980 in just about everything. back in the 80s syn was vastly superior. Now, a good dino is pretty darn close to syn so it may be harder to justify the price difference. I have never had a complaint about syn and never torn down an engine using syn, but from what I can see, it seems the engines are cleaner and last longer than I keep them. Course never had a problem with dino in the 70s either, but I was religious about oil changes. I have seen many old dino engines with terrible oil problems, but I think that is less common now.

If you change oil regularly, especially every 3,000 miles and you don't tow or drive in high heat or extreme cold or go for long drain intervals or don't want that extra 10 horses, then dino is a fine choice. If you are a manly man whose truck lives a hard life and you want every bit of extra power, then syn is your choice.

I use syn in everything, including my weedwhacker.

If your engine is in decent shape syn should keep it slightly better longer than dino, but for most people it comes down to religion.

Just my opinion,

Jim Henderson

 

Syn will not stick better to moving parts. The advantage at startup is that syn flows better at extreme low temperatures. While I agree with everything Mr. Henderson said above, I personally do not use synthetic engine oil, just synthtetic gear oils. If your truck lives outside and it gets below -30C (-22F), then I would definately go synthetic.

Jim

 

I also agree with Mr. Hendersen. The only thing that I use syn. oil in is my air compressor in the shop. I have never seen a need for it. I can say that the reason for the popularity of synthetics or blends in the diesel truck engine world was strictly in be able to increase oil change intervals. If an owner operator can double his milage between oil changes, that is alot of money saved. Synthetic and syn. blends can support a higher volumn of additive package. Which makes oil "last longer" there fore the longer oil change intervals. There are alot of guys running engines 25000 miles on an oil change now. Used too alot of guys would only run 10 to 12000. I change my oil often so I can't see a need for it for me. As far a "dry start up". If you have the right vicosity for your climate how can you go wrong with syn. or "non-manipulated" oil. Engineer at Cummins loved that term. lol.
What is the actual reality of a "dry start up". In theory there such a thing, but to cause excessive or damaging wear? I was checking the oil pressure on a N14 Cummins at the cam one time. I was in a hurry and BSing alittle and when I took my test gauge off I cranked the engine without taking my fitting out of the block and before the engine hit I soaked the guy next to me with oil. It was funny. I owned him one. All three of my trucks show oil pressure right at the time they fire off. Or with-in a second. In that time the oil went from the pump through the block to the cam bearing and through a five foot hose to the gauge. The bearings don't drain dry. A "dry damaging start-up"???????
One question I have and by all means I am NOT being a smart#$@, con sythetic user. Viscosioty is the resistance to flow compared to water. If synthetic 10w40 does flow better then non-synthetic 10w40 in cold weather shouldn't the rating reflect that??? I can see where synthetic oil has the potental for alot better performance. I have been making my living with a wrench for 20 years and I have seenalot of things and heard twice as much. You have to look through alot clouds to see the sun. Everybody have a lovely day.

 

I think the reason that the ratings on synthetics are not wider is due to two things:

1. The ratings are done at not-very-extreme temperatures (Low temp at freezing?).

2. It would confuse the consumer, who would not understand why the numbers were not the same as in his owner's manual.

Perhaps somebody here with more 'inside' knowledge can comment. I do know that the original, and probably still best reason to use synthetics is less change in viscosity with temperature. However, this probably makes little practical difference except in long term Arctic conditions.

 

BTW I do not like extended oil change intervals with Syn for normal cars and trucks. I have been using syn like I said since 1980. Back then extended drains were recommended even upto 25,000 miles. I usually change syn at 7500 miles and my driving style fits under the owner manual "Severe Duty" guidelines.

I did go with extended drains maybe 3 or 4 times in the past 26 years and did not like any of those times. Usually when I change oil at 7500 the oil is either a nice dark honey color or black, depends on the engine. BUT, with drains at 15,000 miles the oil is a dark muddy color with that weird rainbow scum on the surface. Probably just personal superstition, but I don't like that look so I do not do extended drains. Nothing scientific about my opinion here.

Interestingly most syns have backed off the 25,000 mile change and some have come out with "special" extended drain versions. What happened to regular syn being good for extended drain? Probably marketing differentiation

If you do extended drains you would probably be wise to send the oil out for analysis everyonce in awhile and should change the filter at the normal interval. If I am changing the filter, I might as well do the oil so to me extended drains don't make sense.

The long haul truckers have a different driving environment and the oil sump is huge so they can go longer.

Just my opinion,

Jim Henderson

 

SAE J300 is the standard for viscosity ratings, and yes, it is somewhat confusing to the public. The higher number 30, 40, etc. is easy to understand because it is measured at the boiling point of water.

The W rating is measured at different temperatures (not 0F nor 0C as some people think). 5W is 5W, dino or syn, but if you look at pour points from the oil company data sheets, synthetic flows better at temperatures below those used in the SAE J300 standard.

Here is a link that summarizes SAE J300.

http://www.infineum.com/information/viscosity.html

Jim

 

O.K., and thanks for the details. The point is.. " synthetic flows better at temperatures below those used in the SAE J300 standard."