Ok See if this makes sense to you guys.

In my Expedition I'm using 10w30 Amsoil year round.
I used to go with 10w30 in warmer months and 5w30 in winter here in Jersey.
I'm using 10w30 Amsoil all year because I feel being it's a synthetic and flows better in cold weather.
So with that in mind I feel a 10w30 synthetic would flow just as fast or faster than conventional 5w30 oil in very cold weather.
I've read article that state 10w-30 is fine but nothing is said of cold weather.
What is said is the auto manufacturers must meet an MPG average and lower weight oils gets better gas mileage.
A 10w30 may cost a little MPG but protects the engine better.

What do you think?

 

Well, my opinion is to use a good petroleum based oil (like Castrol
5W30), and change it every 3K miles!!!! Synthetic is going to get
dirty at the same rate as a petroleum based oil from the combustion process.....Don't believe what the Amsoil marketeers
tell you trying to justify the high cost of their oil!!!!

You wanted an opinion, now you have it!!!!!!

 

Thanks Bob.
I appreciate your imput even if I don't agree with your assessment on synthetics.
I believe synthetic oil is better in cold and hot weather.
Just my opinion.
Also have read the additives don't wear as fast in synthetics than dino oil.
I change it every 6000 miles.

How about the flow of a 5w30 dino vs a 10w30 synthetic in very cold weather?
The flow the same?

 

I could guess, but it would only be a guess....

Instead, find the pour point numbers for each oil in question (typicaly in MSDS or Mfgrs. tech sheet). That would be your best way to make an educated decision.

EDIT: a quick check gave this info:

Formula Shell 10w30 pour point: -41 deg C / -42 deg F
Amsoil XL-7500 5W30 pour point: -43 deg C / -45 deg F
Amsoil "100% Synthetic" 5W30" pour point: -48 deg C / -54 deg F.

Looks like the XL-7500 is about the same as the Shell 5W30.
The "100% synthetic" (whatever that is - I thought all Amsoil products were 100% synthetic) looks better.

How often does it get below -40 deg F. where you live?

 

I guess that's the best way to go,Brian.
I do believe it's logical that a 10w synthetic would flow as fast or faster than a 10w dino oil in a cold climate.
Just trying to see if the majority would agree or disagree.

 

Thanks Brian for the research.
I use the 100% synthetic Amsoil.

-40 Never!
I guess I'll just go back to 5w30 Amsoil in fall,winter and 10w30 spring,summer.
I do about 10K miles a year.
I change my oil twice a year.
1st week of April and Nov.

Thanks again,Brian.

 

Yes, a 10w30 synthetic will flow better at low temps than a 10w30 dino - but how much better is difficult to determine, and whether or not a 10w30 synth flows better than a 5w30 dino depends on the particular oils you are comparing. It's tough to compare one to another - even the pour points and pumpability limits only seem to tell a portion of the story.

I do think that with the 4.6L and 5.4L V8s, it makes sense to have an oil that can circulate quickly - partially because of being OHC and partially because they seem to have a very fast cold idle (for emissions reasons, I'm told). So, I would rule out using a 10w30 dino in the winter in a cold climate, and the jury is still out on a 10w30 synthetic in my opinion. I'm currently running 10w30 Mobil 1 in my truck, and it was okay on cold Michigan mornings - but not spectacular, as I still had more noise on cold starts than I'd like. I *probably* won't use 10w30 next winter, but I really haven't decided yet. After having both the 5w30 M1 and 10w30 M1 in my truck about 5,000 miles each, I think the 5w was just a tiny bit quieter on cold mornings. Both oils provided quieter cold starts than the factory Motorcraft 5w20, but this isn't really a huge surprise.

So, my recommendation would be to stick to the 5w30 winter/10w30 summer - but if you had an older engine I'd recommend the 10w30 oil year-round (or even thicker yet). Personally, I have two more cases of 10w30 M1 to use up (found it on sale) so that will take me through until mid-summer or so - at which time I'm probably going to switch to something else. I've heard good things on other oil boards about the European-car formula 0w-40 M1, and about the Delvac 1 5w-40 - so I'll probably switch to one of those and see how it goes. If I can find it, it'll probably be Delvac 1 - from the specs and oil analysis (what's the plural of analysis?) I've read, it sounds almost exactly like what I'm looking for.

However, you're an Amsoil guy, and I'm not that familiar with their products - maybe they have something that'd work good in both winter and summer. On the other hand, why not just run 5w-30 year-round? Since you're changing it pretty often it should have no problems staying in grade, and IIRC Amsoil 5w-30 is thicker when warm than many other 5w-30 oils (like Mobil 1). Of course, if you're changing it twice a year anyway it really doesn't matter which one you use in summer - since it would cost the same either way.

As far as what Bob said, different oils do not "get dirty" at the same rate - it depends on the basestocks, additive packages, and so on. For actual dirt, it depends on the filter. Anyway, different types of oils (PAO, ester, group III, group II, and so on) behave differently when exposed to contaminants - plus, much of the problem isn't actual 'dirt' but acid, and neutralizing that depends on all sorts of factors. Not that I'm any kind of expert, I've just been doing a bit of research lately - and so far the main thing I've figured out is that there are people out there who are even more obsessed with oil than *I* am.

LK

 

Thanks for your imput LK.
I see we sort of think alike on the oil weight issue.

As far as oils getting dirty.
Mobil 1 in the beginning advertised 25000 mile changes.
They stopped that advertising because people were voiding their warrantees.
If you call and ask how many miles between changes they will say follow your manufacturers recommendation.Even if you say you're out of warranty.Try calling Mobil.
Amsoil still says 25000 miles or 1 year with only filter changes.

I do 5-6000 miles on a change with filter.
Twice a year.
I'll be switching over to Amsoil on my wife's Grand Prix soon too.
I have a '69 Corvette that I use Amsiol and change the oil once a year.But I only do about 2500 miles a year.

Surely if a company states 25000 miles between changes 6000 miles on the oil is nothing.

 

Redvet, I think you may want to check the Amzoil product you are using. Most of Amziol products are not API certified and your Ford requires an API cerified oil. The only product of theirs that I am aware of is the 7500XL. It is not the usual extended oil change product that Amzoil is known for. Recommended oil changes at 6 months. Concerning the weight of oils I would suggest using the 5w-30 and stay with it.

 

Hi Flash.
I'm aware of Amsoil non API rating.Been using Amsoil in all my vehicles since '83 without a problem.
The 7500XL series is a different formula synthetic.
Amsoil has been around for over 30 years with a great product reputation.The distributors may be a problem but the product is great.
I buy my Amsoil off the shelf at a local speed shop.Do have to order the filter if I chose to go with a Amsoil filter.
I go 6 months between changes.

Actually the regular synthetic is ok for warranties.

"The use of AMSOIL 100% Synthetic 5W-30 Motor Oil will not void new vehicle warranties. New vehicle warranties are based on the use of oils meeting specific API and ILSAC service classifications and SAE viscosity grades. AMSOIL 100% Synthetic 5W-30 meets the current API, ILSAC and SAE requirements (as labeled) and is perfectly suited for use in any new vehicle stipulating those requirements as manufacturer's recommendations."

If the above paragraph wasn't true a big oil company or a consumer would sue for false advertising or the government would be on their case.

 

The Magnuson-Moss Warranty Act will not offer you protection by Ford should you have an oil related failure. That's the law.

 

Does that include the warped head oil leak problem on the '99 5.4's 29500 so far.*Fingers crossed*

I guess I'm rolling the dice then.Been rolling the dice for years with Amsoil.Hope snake eyes doesn't come up.
Thanks for your imput Flash.


Oil filter recommendation?
I use Motorcraft in Fall/winter.I do less miles.Amsoil spring/summer.

 

A warped head or leaking head gasket is not considered an oil related problem. There are 2 Technical Service Bulletins on your truck issued by Ford concerning your problem. The first was issued January,02, number 02-1-4, which concerns the head gasket leaking and the other is 02-2-3 issued in Feb 02 concerning the head. You may need to give these numbers to your Ford dealer and these repairs should be covered by warranty.

 

Flash I hope you know I was kidding with you on the head leak thing.
Thanks for those Tech service bulletin numbers.I hope I never need them.

 

While in my personal opinion I believe that Amsoil is overpriced, and that extended drain intervals are ill-advised, its your truck, and if thats what you want to do, then more power to you.

That said, I have experience with higher weight synthetics in colder climates. I had an old bronco 2 that I would run 20w50 Mobil 1 in year round. I used the higher weight to keep oil pressure in check. It always cranked right over, quite fast, even on the coldest of days. When I was running any type of dino, it cranked quite slowly, with 5w30 being a LITTLE better. So I think you're quite safe with the synthetic 10w30, even if I dont agree with the brand. Anybody that even mentions Amsoil around here gets told about it rather quickly. I know, I've done my share of "telling." Have fun, and dont spend too much!