so i just changed my gear oil in my front and rear diff's and holy hell, i almost puked when i cracked em open, i swear, that is the most horrid smell ever. back on topic, being that both have a magnetic drain plug i noticed almost no shavings in the rear diff, but a rather large amount in the front, basically the rear magnetic was covered but only by a lil bit, the front had like a bit of buildup on it, about 3 or 4 times as much as the rear...is this odd or is this jsut the way it goes?

also, for the grease fittings on the u joints, i cant seem to get grease into them, i can just replace the fittings rather then the whole joint correct?

 

I only know to the fittings, they are replaceable, or at least you can buy them for that application.

 

I wouldn't sweat it but I would change the diff fluid a bit more often.

 

I can't see why the front drain plug would have more fragments than the rear unless the rear was changed more recently or the front has been abused some way.

 

how often do you use the 4x4? the front does see more abuse then the rear because when the wheels turn it puts it under more stress, something that the rear doesn't have to deal with. do you use the 4x4 when its dry?? anyways i would just change the fluid more often in the front and call it a day.

 

Why more metal in the front dif? Isn't it obvious? The rear is broken in XXXX amount of miles. Whatever was going to wear on the gears is worn, many miles ago.

The front see's dramatically less use than the rear. If you could compare how many miles are on the rear Dif compared the front, you'd probably would have seen just as much metal shavings on the rear mag-plug as you do on the front now when the rear reached the same amount of mileage as your front is seeing NOW. *breeeeaathe* lol

Not to mention the front dif fluid gets changed less than the rear for the very same reason, it's used less and the oil doesn't break down as quick.

I've seen the same thing on my truck.

As for the smell, no idea other than really old fluid with water and dirt in it.

FYI, another thing if you are running the stock dif breathers (little cap with spring and seal) make sure its not packed with grease/dirt or whatever. Friend of mine blew out her rear axle seals because the plug was packed, almost cement like. She didn't believe me till the shop charged her $1100 to install new seals and told her the same thing. Women. I never got the chance to investigate her rear 3rd more but she stopped driving it because it shimmied/rattled bad on the freeway which led her to look under the rear end to discover all the gear oil on the tires. I could almost turn the driveline 1/3 of a rotation which is IMO the cause of the shimmy... waaay to much play in the gears (backlash). I wonder if the shop fixed it. ลลลล for $1000 i hope they did.