Need to change out the gear oil in my rear differential, but i'm kind of lost.

[signorgreenleaf]

I have a 97 Ford Ranger XLT 2.3L with an axle code of 87 which is an open diff with a 4.10 ratio. Not sure if any of that info is necessary but I figure I'd include it.
I found this list but it makes no mention of the rear differential for my truck so this is where I became lost.

Ford Ranger Fluids & Capacities

www.therangerstation.com

Can someone please tell me how much gear oil I should buy and which kind?

 

[ericbphoto]

I’m pretty sure you have the 7.5”. The volume on that hasn’t changed since the stone ages. Should be 5 pints. With an open diff, I don’t think you need the friction modifier. But most of the oils already have it in them. It won’t hurt anything. Have a little extra in hand in case 5 pints doesn’t quite fill it.

 

[signorgreenleaf]

I’m pretty sure you have the 7.5”. The volume on that hasn’t changed since the stone ages. Should be 5 pints. With an open diff, I don’t think you need the friction modifier. But most of the oils already have it in them. It won’t hurt anything. Have a little extra in hand in case 5 pints doesn’t quite fill it.

I was just going by the list I posted. Mind pointing me in the right direction for the oil type? Im worried I may buy the wrong one.

 

[ericbphoto]

I would use 80w-90. Owners manual would tell you for sure if you had it. There are some owners manuals somewhere in our tech section.

Owners Manuals - The Ranger Station

Ford Four Wheeling Supplement 2024 Ford Ranger Owners Manual 2023 Ford Ranger Owners Manual 2022 Ford Ranger Owners Manual 2021 Ford Ranger Owners Manual 2020 Ford Ranger Owners Manual 2019 Ford Ranger Owners Manual 2011 Ford Ranger Owners Manual 2010 … Continued

www.therangerstation.com

 

[signorgreenleaf]

I would use 80w-90. Owners manual would tell you for sure if you had it. There are some owners manuals somewhere in our tech section.

Owners Manuals - The Ranger Station

Ford Four Wheeling Supplement 2024 Ford Ranger Owners Manual 2023 Ford Ranger Owners Manual 2022 Ford Ranger Owners Manual 2021 Ford Ranger Owners Manual 2020 Ford Ranger Owners Manual 2019 Ford Ranger Owners Manual 2011 Ford Ranger Owners Manual 2010 … Continued

www.therangerstation.com

I have the owners manual for my truck but I didn't see anything on there about gear oil. Thanks for your help.

 

[ericbphoto]

I have the owners manual for my truck but I didn't see anything on there about gear oil. Thanks for your help.

Page 311 for the type
A few pages earlier for the quantity

 

[Dirtman]

My 7.5 takes a little over 2 quarts. 80w90 is fine and what came in it from the factory, 75w90 is better (synthetic), ford calls for 75w140 now for some stupid reason. No friction modifier needed on an open diff. (75w90 and 75w140 already have it anyway though).

 

[SenorNoob]

75w-140 is what my Explorer rear axle calls for. It's starting to get reasonable in price if you look around some.

 

[Dirtman]

Ford changed the "rule book" and now says 75w140 goes in everything no matter what was originally in it from the factory, or what the original owners manual calls for. Bring in a 1965 F100 or a 2020 ranger and they will put 75w140 in it.

Why? They are cheap and don't wanna stock more than one type of fluid plain and simple...

I'm not saying using 75w140 is bad, it's great stuff. But using 80w90 or the synthetic version 75w90 is just as good in 99% of situations. The only real reason for 75w140 is extreme heat towing.

 

[ericbphoto]

His owners manual calls for 5 pints of 80w-90. There’s really no reason to guess.

 

[pjtoledo]

both '97 and '05 call for Ford specification WSP-M2C197-A ( referring to the 80-09 stuff. )
that number will be on the back of the oil containers.

FYI, it's called " hypoid gear lubricant "
hypoid refers to the design of the gears and how they mesh, not the oil.

think of it as "lubricant designed for hypoid gears" and the stuff literally stinks like sulfur.