2015 F150 front and rear diff fluid

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All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?
 
I'd use what Ford Specs because your gonna need 2 qts for the back and close to 2 qts for the front anyway.
 
I'd put in 75W90 and not worry about it. The viscosity is so similar it wouldn't surprise me if Ford actually uses both fluids on the assembly line.
It's not like your going to a 75W140.
 
Originally Posted by skyactiv
I'd put in 75W90 and not worry about it. The viscosity is so similar it wouldn't surprise me if Ford actually uses both fluids on the assembly line.
It's not like your going to a 75W140.

My 2013 calls for 75w-140. There's a pretty good case to run such things.
 
It was spec'd both ways on my GM 4WD's …
put 75w90 front and rear on both vehicles … always have …
 
Originally Posted by 4WD
It was spec'd both ways on my GM 4WD's …
put 75w90 front and rear on both vehicles … always have …

Ditto for my Alaskan Silverado.
M1 LS 75W-90 in the front and rear. Great syn gear oil... no troubles.
This truck has 175K miles on it.
 
Since you're non-limited slip, my vote goes to Mobil Delvac 75w90. Great oil without needed friction modifiers. Red line is the only aftermarket option for 75w85 that I know of. Can't speak for Ford's version, but Toyota's 75w85LT is $$.
 
Originally Posted by Buzzinhalfdozen
All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?


How do you use your truck ??? Any heavy towing or hauling ?
 
Originally Posted by Buzzinhalfdozen
All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?


From your own manual: The 80w90 is conventional. The 75w-85 is synthetic. They are just trying to save you a few bucks because the front diff does not get as much use. GM has spec'd this on some of the 1500's. Read the [censored] manual!
smile.gif
 
Originally Posted by kstanf150
Originally Posted by Buzzinhalfdozen
All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?


How do you use your truck ??? Any heavy towing or hauling ?


Nope just drive predominantly. I tow a small trailer here and there but that's about it.
 
Originally Posted by OCDoiler
Since you're non-limited slip, my vote goes to Mobil Delvac 75w90. Great oil without needed friction modifiers. Red line is the only aftermarket option for 75w85 that I know of. Can't speak for Ford's version, but Toyota's 75w85LT is $$.

That would be a good choice. Are the LS modifiers in certain offerings going to hurt anything, such as in the front?
My experience says no.
 
Originally Posted by SteveG4
Originally Posted by OCDoiler
Since you're non-limited slip, my vote goes to Mobil Delvac 75w90. Great oil without needed friction modifiers. Red line is the only aftermarket option for 75w85 that I know of. Can't speak for Ford's version, but Toyota's 75w85LT is $$.

That would be a good choice. Are the LS modifiers in certain offerings going to hurt anything, such as in the front?
My experience says no.

Not going to hurt anything. The Delvac will last longer, as it will have slower oxidation from lack of LS additive you don't need.
 
Originally Posted by Snagglefoot
Originally Posted by Buzzinhalfdozen
All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?


From your own manual: The 80w90 is conventional. The 75w-85 is synthetic. They are just trying to save you a few bucks because the front diff does not get as much use. GM has spec'd this on some of the 1500's. Read the [censored] manual!
smile.gif



If ford actually cared about saving the consumer money they wouldn't spec a fluid that's $27 a quart currently at Amazon with zero local availability. Also I've read my manual. I know what it says. I was looking for others experiences.

It looks like I'll be grabbing some 75w-90. Thanks folks.
 
I'd run syn in the front as well - ideally for thinner cold weather characteristics. It's a waste to spin all that stuff when just needing RWD. I *really* wish there was a manual hub offering for these things so we could disconnect the front driveline unless we actually need it. It gained me 1 mpg in past on a pathfinder.
 
The reason they run conventional in the front is because it sticks to the gears much better than syn. If you look in gearboxes on Ag equipment that has syn gear oil in it on machinery that sits for months at a time. The part of the gears that are above the oil line the gears will rust. They can sit for 10 years with conventional oil and will never have rust on them.
 
Originally Posted by meep
I'd run syn in the front as well - ideally for thinner cold weather characteristics. It's a waste to spin all that stuff when just needing RWD. I *really* wish there was a manual hub offering for these things so we could disconnect the front driveline unless we actually need it. It gained me 1 mpg in past on a pathfinder.

These trucks(or most of them) disengage the front driveline when in 2wd via vacuum operated hubs.
 
Originally Posted by Buzzinhalfdozen
All,

My 2015 f150 specs 80w-90 in front and 75w-85 in rear. It's a non-limited slip 3.31 no e-locker. Viscosity of the 75w-85 at 100 degrees Celsius is 11.53 cSt. I'm guessing it's a fluid speced primarily for fuel economy. I would like to run a single fluid front and rear that is easy to acquire.

Anyone out there running a 75w-90 front and rear with good results?

I have used 75w-90 in my F150 diffs. without problems and will continue to do so.
 
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