Gear oil weight options 87 V10? 10 Bolt? Minor whine

[Joe T]

Hey either my transfercase or rear end has a minor whine to it under acceleration at moderate highway speeds.

It doesnt have the G80 option so I assume 80-90 gear oil is what its called for.

Can I run a heavier weight. I am in a warm climate, houston. Truck came from a colder climate prior to me getting it.

 

[MrMarty51]

Yeah Joe, I`m not sure about the source of the whine.
My 87 V1500 once picked up a whine so I booted Her out the door. Just kidding.
It did though, from the rear differential, was on the interstate cruising, all was fine. came upon the exit I had to take, let off of the accel pedal and only then did I hear the whine. turned out it was the ring gear carrier bearings.

 

[Joe T]

I plan to first put thicker oil in it and try Lucas in the tcase. Its not a daily so I am not to worried.

 

[dvdswan]

You can pop off the diff cover and check the wear pattern. That will help diagnose one or the other. Chances are its the diff though.

 

[Joe T]

Yeah I am wondering which fluid to change first. I have a couple quarts of lucas stop slip I could use in the tcase as that is pretty easy to change out.

If that doesn't work I’ll try to run a good 85-140 in the rear. Its a warm climate here so should be ok.

 

[akchevrolet]

Yeah Joe, I`m not sure about the source of the whine.
My 87 V1500 once picked up a whine so I booted Her out the door. Just kidding.
It did though, from the rear differential, was on the interstate cruising, all was fine. came upon the exit I had to take, let off of the accel pedal and only then did I hear the whine. turned out it was the ring gear carrier bearings.

My 87 r10 does the same whine when I let off the accelerator stops when i put it in neutral.