what weight of gear oil and exactly how much should i put in my 300 front and rear differentials?

 

75 or 80w/90

i use synthetic. If its like my forman, there's a drain bolt on the bottom of the diff (under the skid plate), 1/3 way up there's a check bolt, then teh large fill hole at the top. Drain the old fluid out (let it drain for awhile, its thick and takes awhile to fully drain), then put the drain bolt back in, take out the check bolt and fill through the top hole until the oil comes out the check bolt hole.

The front is the same, but there's only a drain and a large fill hole. Fill the fluid until it just spills out the fill hole.

they both only use about 1/2 cup of oil each or so.

 

add limited slip additive to the front.

 

did the 300's have a clutch type limited slip front diff??? You only need limited slip additive if it has clutch packs in it. The new ranchers have cam followers, dont need additive for that either.

 

does anyone know if the 94 300 4x4 has clutch packs in it???