Front Diff Fluid question...

[LUV24BY]

Is it just me, or does anyone who has a FJ/FZJ80 notice their Front Diff Fluid gets dark much faster than the rear diff fluid. As they both are running FT, why would the rear diff not get as dirty/dark? I mean, within 5-7k miles it's dark, even after having the front axle redone & serviced.

Is this common? Normal? If not, what does dark fluid indicate?

I have a 93 Factory Locked 80, 197k on the truck and running Dino in both ends (mechanic said it would be ok to run...vs. the LSD fluid)

Could someone shed some light on this? I have done a search and only found issues with the front axle itself rather than the fluid color.

What's the PM avg. mileage to R&R the Front fluid?

TIA!

John

 

[Tools R Us]

It is normal. Some moly grease migrates from the knuckles into the diff, so the fluid needs to be changed more often than other types of axles.

 

[LUV24BY]

It is normal. Some moly grease migrates from the knuckles into the diff, so the fluid needs to be changed more often than other types of axles.

Thanks Tools! So going the Factory High $$ stuff doesn't do much else than to drain the wallet faster?

What should the interval be? Is the Moly grease cause harm or problems to the gears/lockers?

J.

 

[canman]

I just replaced my rear diff fluid tonight and it was very dark, and I had replaced both the front and rear at the same time last year. It did have what appeared to be a bit of a grey like paste on the magnet which I haven't seen before. I had changed the diff fluid in the front about 6K miles ago and it's appearance is more grey and "soupy" as others have mentioned due to the knuckle grease leaking past the seals. FWIW I used Castol 75W-90 Syntec.