Oil weight

[4winds4me]

I have a 2019 Thor class c e350 v10 the oil cap states 5-30 wt. I bought 5-20 wt full synthetic Mobil -1 and used it ,not thinking it was a big deal , can I run this weight without a problem, My toad is a 2005 2dr Jeep.

[SuperD]

You can but I wouldn’t, the heavier oil is a lot better since the V-10 makes a lot of heat!

[EA37TS]

Why can’t you follow Ford’s recommendations that are listed in the owner’s manual?

[cpmath]

But EA if he followed what the manual said he wouldnt be able to post his question here and have everyone here for the next six weeks reply to him.

[ducksface]

Oil is often a religious discussion.
I doubt anyone here can tell of an oil related failure that's happened due to a reasonable oil viscosity change within the last 59 years or so.
But
I'd follow the Ford recommendation since your knowledge base has little to do with oil types.

It comes across as reinventing the wheel due to some blurb about synthetic oil or some sale somewhere.

Take it back, get the correct oil type.

[16ACE27]

You know 5W-20 used to be what Ford recommended for these V10s as well as many of their other engines.

[Muggs]

I use what manual and fill cap say, 5w-30. Due to slower miles buildup I change at 4,000 miles, not 5,000 as manual recommends. I use the Motorcraft blend.

[4winds4me]

Since my RV was in storage i as unable to get to the manual to see the correct oil weight so I watched a couple of videos on changing oil on a class c Ford , both used 5-20 wtFound out ford changed back to 5-30wt later on AFTER I had bought the 5-20 so thanks for your response I’ll get it corrected, BTW not trying to start another oil war thread..Merry Christmas

[Pete'sMH]

Couple of years ago I mentioned to my Ford service writer that my coach needed 5W-30 and he didn’t believe me! Said they’d always used 5W-20 and probably still would. I’m sure he’s more current now.

[axis earl]

Originally Posted by 4winds4me

I have a 2019 Thor class c e350 v10 the oil cap states 5-30 wt. I bought 5-20 wt full synthetic Mobil -1 and used it ,not thinking it was a big deal , can I run this weight without a problem, My toad is a 2005 2dr Jeep.

No, not a big deal. Next time, I would buy what the fill cap says. Our 2016 E450 stripped chassis also said 5w-30 and our service guys didn't quite believe me. Our 2019 F-53 filler cap says 5W-20.... The service manuals can be different than the filler caps I have found and has been confirmed by past discussions on the forum.

[Lt Keefer]

Once upon a time the only bashing going on on this forum was directed at Thor or its suppliers. It seems times have changed and the moderators are now allowing personal attacks.

[EA37TS]

Food for thought, explained by Mobil 1, for those that may not know about oil viscosity.

What is oil viscosity and what impact does this have?
Viscosity is a measure of the resistance of a fluid’s flow. The thicker (high viscosity) of an oil, the slower it will flow.

Most oils on the shelves today are "Multigrades", which simply means that the oil falls into two viscosity grades (i.e. 10W-40 etc). In a 10W-40 for example the 10W bit (W = winter) simply means that the oil must have a certain maximum viscosity or flow at low temperature. The lower the "W" number the better the oil's cold temperature performance.

The 40 in a 10W-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number, the thinner the oil: for example, a 30 oil is thinner than a 40 oil at 100°C.

In a cooler climate someone may have better luck with a 5W20 than someone that is in a warmer climate. Also, the more wear that is on an engine the greater the need for a higher viscosity oil.

Quite a few owner's manuals today still include a matrix that recommend a different oil viscosity based on temperature or operating conditions.

Again, food for thought.

[Golfbum18]

Originally Posted by 4winds4me

I have a 2019 Thor class c e350 v10 the oil cap states 5-30 wt. I bought 5-20 wt full synthetic Mobil -1 and used it ,not thinking it was a big deal , can I run this weight without a problem, My toad is a 2005 2dr Jeep.

Had that problem with mine....Ford book says one thing, cap says another. I went with the book.

[Golfbum18]

Originally Posted by cpmath

But EA if he followed what the manual said he wouldnt be able to post his question here and have everyone here for the next six weeks reply to him.

If you can't come here with a question hoping for a good answer, where do you go? Isn't the RV community known for friendlyness, good will, and helping?

[wingnut60]

"Take it back, get the correct oil type."

This was a particularly insightful statement considering he said he already used it...

[Pete'sMH]

I looked in my 2019 Ford F-53 manual today and it said to use 5W20 but listed 5W30 as an alternate choice with no restrictions or conditions on the choice. I’m using the 20 but wouldn’t be concerned in the least if I accidentally bought the 30. Especially if it was summer or I was snowbirding in warm climates.

[The Gritz Carlton]

I use 10W30 Synthetic year round in everything except the diesels. Our weather here doesn't get so cold you need the super thin stuff at startup. Part of the 5W promo is for added fuel economy...it helps with their "cafe" numbers.

[The_Breeze]

Originally Posted by Lt Keefer

Once upon a time the only bashing going on on this forum was directed at Thor or its suppliers. It seems times have changed and the moderators are now allowing personal attacks.

What'd you expect. Basher's from NY. Bob is different. Bob doesn't belong in NY, do you Bob

[The_Breeze]

Originally Posted by The Gritz Carlton

I use 10W30 Synthetic year round in everything except the diesels. Our weather here doesn't get so cold you need the super thin stuff at startup. Part of the 5W promo is for added fuel economy...it helps with their "cafe" numbers.

This touches on the reason for the lower viscosity number (e.g. 5W). There was a time when the best you could do was 10W. In super cold temps, oil couldn't flow quick enough, resulting in main journal, cam bearing and lifter wear. The lower viscosity numbers helped the oil flow more quickly, coating the surfaces before heat build up, which happens quickly in the rotating mass, burned the bearings. The winters are long in some places. If that scenario plays itself often enough, you're tearing the motor down to replace bearings.

[The Gritz Carlton]

True...I worked 15 years as Marketing rep for Amoco (a few moons ago) and spend 8 full weeks off and on in the Naperville, IL Research Center. Amazing what oil goes through before it hit the "cans". Without all the additives, it wouldn't last one mile. Viscosity Index Improvers was a big one.