Flashpoint for 75W90 synthetics

[3930dave]

How big a deal is Flashpoint for gear oil ?

Application: E350 7.3L 3.55open, will be hauling up to 10K# limit.

I have used Mobil1 75W90 in my rear wheel drive station wagon recently - I have faith it will perform great there.

I was going to p/u more of the Mobil1 for the E350, but I happened to compare specs with Amsoil.

Mobil 1 Synthetic Gear Lubricant LS 75W-90

AMSOIL - Synthetic Gear Lube SAE 80W-90 (AGL)

Flashpoint on the M1 is 150C, Amsoil AGL is 218C. Quite a difference.

Yes, the Amsoil AGL is actually an 80W90 (what Ford specs) but Flashpoint does not appear to be that different in the Amsoil Severe Gear 75W90, so I don't think (?) this Flashpoint difference is driven by the lower viscosity number.

(Funny though, about the Amsoil SG 75W90, it seems to be showing a Minimum of 150C Flashpoint, which would be in-line with the Mobil1. Sigh.... games on datasheets.... ya really gotta read 'em 2,3 times.... at least I do ).

As I live in Canada, I want/need the low temperature performance of a synthetic gear lube. Mobil1 might go on sale now and then, but at regular prices, the Amsoil AGL 80W90 and the Mobil1 75W90 retail for about the same $.

What I don't have is a good feel for consumption rates vs. Flashpoint, esp. for gear oil. Comments ?

For my money, I'm leaning towards the Amsoil AGL 80W90, as it's Flashpoint is 68C higher.

Rgds, D.

 

[Transit]

The flash point is the temperatures at which the oil will auto ignite.

Converting: 1.8 x C + 32 = F

1.8 x 150c + 32 = 302F for mobile one

1.8 x 218c + 32 = 424F for amsoil

If you are running temperatures that high you have other problems.

I would not worry about it.

 

[3930dave]

Thnx Transit...... I'm guessing the main factor in differential gear oil consumption would be seal condition, but I really don't know how big a factor the oil volatility is re. consumption, hence the post here. I do hear your point, re. Operating Temperature.

The only thing I have experience with in this regard is motor oil. Many motors will consume less synthetic than conventional - my guess - this is due to a combination of better sealing properties and Flashpoint of the synthetic.

Partly I'm trying to compensate for my own behaviour..... I will check motor oil levels fairly often, differential levels all too rarely.

Rgds, D.

 

[HarryVanderpool]

The flash point is the temperatures at which the oil will auto ignite.

That is incorrect.
Flashpoint is the temperature that a vapor os produced that can burn.
Auto ignite in most cases is much and often many times higher.

 

[3930dave]

Thnx K7 !

I have not towed this heavy before, and have known people that have done in differentials towing.... I was surprised to see the difference in specs, it seemed larger than I would have thought likely.

Cost is only a secondary concern. Stock is 4 quarts, if I upgrade the cover it may be closer to 6 quarts, but no matter.

I hear you... either one should do the trick. Rgds, D.

 

[Soundguy]

The flash point is the temperatures at which the oil will auto ignite.

If you are running temperatures that high you have other problems.

I would not worry about it.

ditto that...

soundguy

 

[HarryVanderpool]

So Soundguy choses to "Diddo" inaccurate information yet once again.
Flashpoint IS NOT the same as auto ignition point.
Take a look:
Flash point - Wikipedia, the free encyclopedia

 

[3930dave]

It is a Dana, that reminds me, I was just under there, meant to write down the Dana #..... I usually hear good things about Dana, just trying to take the best care I can of a decent HD axle. :thumbsup:

I hear you on the 1/2 tons..... I wanted to go this heavy as I'm not a fan of being xyz+ miles from home with a multi-ton trailer and a beat to death 1/2 ton.

Thnx again K7.

Rgds, D.

 

[Soundguy]

So Soundguy choses to "Diddo" inaccurate information yet once again.
Flashpoint IS NOT the same as auto ignition point.
Take a look:
Flash point - Wikipedia, the free encyclopedia

it's 'ditto' and I don't know wht youre bone is with me?

I was was ditto'ing the " if you have temps that high you have other problems" portion.

getting around on this lil netbook with 8" screen makes it a tad difficult to fully edit and tweak every single mail sent out.

I'm glad that you focused on that single minor issue, than focusing on the entire post.

oh well.. another to add to the squelch bucket....

soundguy

 

[DarrylH20]

it's 'ditto' and I don't know wht youre bone is with me?

I was was ditto'ing the " if you have temps that high you have other problems" portion.

getting around on this lil netbook with 8" screen makes it a tad difficult to fully edit and tweak every single mail sent out.

I'm glad that you focused on that single minor issue, than focusing on the entire post.

oh well.. another to add to the squelch bucket....

soundguy

I have a few on there myself.