rear axle LSD or not; changing oil???

[dmf415]

hi,
Am the proud owner of a 97 explorer xlt v8 awd.

I want to change the front/rear axles gear oil. The haynes manual says I need to use limited slip additive if I have LSD.

How do I tell if I have LSD, and is this limited slip additive necessary?

 

[AspenX]

Welcom to the site. Yes the additive is necessary. Check the axle code on the door sticker and post it here, someone can tell you what you have.

 

[Blee1099]

What is your axle code according to the door sticker? If it says D2, D4, or L73 then you have a limited slip axle.. Anything else is open.

 

[unclemeat]

You only need the friction modifer if you have a limited slip differential. It will only be in the rear axle.

 

[dmf415]

Thanks for all your help, i will check it out as soon as I can

Checked it out, it says D4 under 'Axle'

 

[double_take]

I had a question about this. I also have the AWD with 3.73 LS rear. In the manual it says this is permanently lubed with synthetic fluid and only requires a change if it is submerged in water.

Is it really necissary to change the fluid?

 

[MrShorty]

Originally posted by double_take
I had a question about this. I also have the AWD with 3.73 LS rear. In the manual it says this is permanently lubed with synthetic fluid and only requires a change if it is submerged in water.

Is it really necissary to change the fluid?

"Permanently lubed for the life of the vehicle" depends on how long you consider the life of the vehicle. One guy over at therangerstation has a quote in his signature that says something to the effect of "Ford expects the lifespan of the Ranger to be about 80K miles." Don't know how true that statement is, but, if you consider the lifespan of the vehicle to be ~100K miles, then no you likely don't need to change the diff fluid. However, if you really want to see your truck last, then you take better care of it than the factory recommends.

 

[Ford_Racing_Guy]

with the conventional Gear lube i believe you are suppose to change it every 100,000 to 150,000 miles

if your using synthetic i don't know, but you might want to change it around 100,000 just so you can inspect the rear-end and then use the LSD additive to prolong the rear-end with new synthetic gearlube

 

[hsinc]

The V8 AWD does have synthetics with friction modifier in it already from Ford. My 99 does. I have 57K miles now, but I will definitely change it before Fords recomendation (which is lifetime, whatever that is). I may change it at 70 or 80 K. I had my front diif just changed, to Mobil 1 syn. Was going to do it myself, but could not get to the fill plug. It appears you have to siphon old fluid out the fill plug. Very hard to reach the fill plug on the V8. Unless you partly drop the diff to remove the back case. That also is not easy.
I just had Mr. Transmission do it for me while they were performing some other maintenance.
Harold

 

[Ford_Racing_Guy]

i think that is what i will do for my fron axle as well, just siphon it out instead of taking the damn axle apart!