calls for 5w-20, OK to use 10w-30?

[trailertoad]

V-10 Ford in Class C motorhome. Used for towing 8,000 pound trailer 100% of the time.

8.500 miles. Thinking 10-30 might add a little extra protection at high oil temps under heavy loads. Good idea or "old-school thinking"?

Right now I run Valvoline. What about adding some Mr. Moly for a 1st line of defense.

I await your experienced replys, THANKS!

Jok

"Hitch of the Future, Today"
www.trailertoad.com

 

[Big Jim]

Old school thinking. That engine was made for thin oil.

10W30 might not damage anything, but it will not protect as well as 5W20.

Use the thin oil and rest easy.

 

[Ray H]

Run 10W-30 for late spring and summer months for added protection and use the severe service schedule for OCIs listed in your Ford motorhome chassis owner's manual.

 

[dustyjoe1]

I run an f-450 in the oilfield, usually has two full sets of tool strings on the rocket-launcher ( over 5k lbs easy) run in the worst possible environment possible. Dust, Heat over 100, Idling all night. I try to drop the oil every 5k miles and usually average just shy of 200 hours per oil change. So far its purring like a kitten at close to 50k. The engine is a v-10 and the oil is castrol gtx 5w20. I've run 10/30 in it a couple of times. but it seems to run much nicer with the gtx 5w20. Take that for what its worth.

r.

 

[ruking77]

Being of the "old school", I'd say go with the 5w20.

While I have to say a lot of the 1.4 M miles I have done were with 5w30 Mobil One(765k), keep in mind that the 5w20/0w20 has literally been formulated to FORD/HONDA's specifications. Ford's specifications are the more stringent. How many 5w30 oils have been formulated to ones' specific OEM specifications?

If you want or need some data or evidence, a lot of UOA's have been done and posted on this web site, which demostrate how robust the 5w20 oil is.

By the way I use 0w20 Mobil One in a 2004 Honda Civic. If I stayed with conventional oil I would chose ExxonMobil Superflo 5w20. But in actuality there are a WHOLE lot of very good 5w20 products on the market.

[ April 10, 2006, 12:07 PM: Message edited by: ruking77 ]

 

[Schmoe]

I'm with RH on this one, as I do this on my F150 5.4 10W-30 in the hot summer time. I feel the 5W-20's will thin out way to much with a lot of heat and if under heavy load, such as what you have. Winter time, I'd drop to a 5W-30. Just not convinced the 5W-20's are "all that."

 

[xtrford]

Thinner oils like the 5w20 actually do a better job at lubricating and cooling your motor under high temps and towing. Smaller clearances, smaller oil passages, high volume oil pump, OHC equals thinner oils like 5w20. As was stated earlier, Ford spec is very hard to achieve and I have seen it in very few 5w30 oils and nothing heavier than that.

 

[Slick17601]

I would go with 5W-20 synthetic such as Amsoil XL-7500 or Pennzoil Platinum.

 

[Mr. Boston]

FWIW - to back up xtrford I'd read on an oil tech site that 5W20 actually does a better job of cooling then the heavier stuff. It was my understanding because it flows easier and exchanges heat faster especially around the piston skirts.

 

[bar1]

xtrford & Mr. B, the difference between a xW-20 and a xW-30 is not enough to make any difference in 'real life'. I have an engine that can use from xW-30 to xW-60 depending on ambient temperature. I've tried them all, everything was equal (oil pressure and oil temperature) except mpg went down when using the thicker stuff (>=50wt)..

 

[Mr. Boston]

I have question for the experts please. Does better mileage via thinner oil (however incrementally small it may be) equal less friction? Or...are we just talking less resistance to movement caused by lower viscosity?

Thanks,

 

[TomJones76]

I've got to say, it seems like modern 10W30s don't have any more shear stability than modern 5W30s, at least based on some UOAs I've seen.
I really think 10W30 is an obsolete grade, except insofar as it is cheaper at the bulk level than 5W30. I suppose it's not obsolete from a cost perspective in that single aspect.
Any Ford-approved 5W20 is a good 5W20.
Pay attention to your tranny. Your application has to be at the edge of your tranny's spec. 15K ATF + ATF Filter changes might be wise.

 

[Bryanccfshr]

I am no expert but
Viscosity = friction
Not in the metal to metal sense but in the fact that resistance to shear is just that resistance to movement do to the force required to move the fluid between solid objects this is fluid friction. While more fluid friction has greater strength to keep two solid objects apart it also takes more energy to move this fluid. How much is too much or too little is the question. The majority of the smartest guys on this board tend to believe that running the thinnest oil possible is the best solution. If the thin oil is providing the wear protection needed the only thing that is accomplished with a heavier oil is the loss of energy to fluid friction. ZThere is no real benefit. Run the thinnest oil recomended.

 

[Mr. Boston]

Thanks for the explanation Bryanccfshr. Makes sense - resistance to movement could be equated to frictional loses however not the damaging metal to metal contact kind.

 

[Buford T. Justice]

http://www.machinerylubrication.com/article_detail.asp?articleid=518&relatedbookgroup=Maintenance

 

[sky jumper]

^ great article. it makes no mention of the theory that new engines are manufactured to tighter clearances and tolerances which gives rise to the need for thinner film thickness and thinner oils. so... does that theory have any credence or not???

 

[Buford T. Justice]

I am wondering that myself. With the exception of Dodges using the 5.7L Hemi that shuts of cylinders when the vehicle is at a constant speed and has a 'cylinder killer' that does have tight specs, I wonder why other engines went to tighter clearances. It makes no sense to me.

Here is a post I just made wondering all of this...

http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic&f=1&t=015051&p=2#000043

[ May 17, 2006, 04:39 PM: Message edited by: Buford T. Justice ]

 

[G-MAN]

quote:

---

Originally posted by sky jumper:
^ great article. it makes no mention of the theory that new engines are manufactured to tighter clearances and tolerances which gives rise to the need for thinner film thickness and thinner oils. so... does that theory have any credence or not???

---

That theory has been discussed on here many times and IMO has been discredited.

When Ford introduced their modular engine family in 1992 does anyone seriously think they knew that eight years later they would be back specifying 5w20 oil for these engines so they tightened up the clearances (even though they were spec'd for 5w30 at the time)?