Valvoline synthetic vs Mobil 1 75w140

[southernjeeper]

Back last year around November I drained my truck's rear differential and put in Valvolines 75w140 synthetic oil. The truck had been used as a fleet truck before I got it at a used car lot that the owner bought off auction. Oil was thin and dark black.

I wanted to use the Mobil one when I refilled but no one local had it at that time and I just went with valvoline synthetic as for price difference being better.

Since the bottles say it's got the additives for LSDs was it okay to not get the diff oil friction modifier that the dealer sells for the diffs spec?


And last question how many of you guys use Mobil 1 full synthetic for your rear diff's in your 1/2 to 3/4tons?

 

[panthermike]

Both are good gear oils. I used Valvoline 75w140 in my old Dana 70 w/ limited slip and had no issues at all. I didn't add any additional FM.

 

[buck91]

M1 costs as much as Amsoil. Valvoline does not. Pretty sure its just branding, but at the price why not go with the Amsoil? Otherwise, why not save money and go with Valvoline?

 

[southernjeeper]

Buck91 --- I just looked that up about the amsoil severe gear 75w140. 40rave reviews and yes it's nearly the same price as the Mobil 1. Just under $20. Didn't see how much shipping would be though hopefully well under ten bucks.

Just might give it a try.

 

[901Memphis]

Don't forget to check out Redline 75w140 it's just as good as Amsoil

 

[dlundblad]

Valvoline is nice because AAP carries it and you can use promo codes.

 

[zeng]

And don't forget a 75W140 is more shear prone and unstable than a 8xW140 .....
in differential applications where viscosity shearing is a 'natural phenomenon' .

 

[SOWT]

Have used both Limited Slip versions in Ford 8.8", 9" and Dana 60, 70 all with Limited slip without adding friction modifier.
Either one works fine. Two days ago priced them at Advanced M1 $21 Valv Syn $13. Need to replace fluid in Ford 8.8 LS and Dana 135 Open Diff. Sticker shock will keep me to just the 8.8 because the 135 takes a little over 3 gallons.

 

[southernjeeper]

So not adding the dealer friction modifier is aaa okay because both brands say they have those additives added already?

With limited slips that are in Ram trucks change 15,000 for severe use and 30,000ish for average not a lot of towing, stop n go, off-road driving. Correct?

 

[SOWT]

Exactly as long as you buy the Limited Slip versions. If you buy the standard versions you have to add friction modifier.
The old man taught me to avoid the dealer at all costs. Of course nowadays friction modifier is easy to find.

 

[cronk]

I like that Amsoil Severe gear is available in 75w110.
It is perfect for the 1/2 ton truck that sees towing duty and needs a little extra protection.

 

[blupupher]

Not sure about Dodge, but I know Ford LS are very picky about FM. Even with the "included" FM, Fords need more (I use the Motorcraft XL-3.

 

[beanoil]

Originally Posted By: blupupher
Not sure about Dodge, but I know Ford LS are very picky about FM. Even with the "included" FM, Fords need more (I use the Motorcraft XL-3.

YMMV...
I've used Valvoline 75w140 with no extra additives twice in a F250 SuperDuty with no problems.
I also ran Delo 85w140 once, without any FM. I needed to add only 4 ounces of Redline LS additive to get rid of chatter.
My experience is that Ford is pretty forgiving in the LS additive department.

 

[MolaKule]

Originally Posted By: zeng
And don't forget a 75W140 is more shear prone and unstable than a 8xW140 .....
in differential applications where viscosity shearing is a 'natural phenomenon' .


They both contain VII's so I don't see how that computes.

Valvoline differential lubes are as good as any on the market.

 

[4WD]

There has always been a steep price delta between the 90 and 140 Mobil 1 gear lubricant
If you look at numbers on their website - I'd say it's GIII vs GIV