Rear end whine

[Truckedup]

I changed the gears in the rear axle last year,7-5/8,from 2.41's to 3.42. Posi.I did it myself with all new bearings and set up the gears as best I could.The pinion preload was done with a small torque wrench and the differential preload and gear pattern seems good.
This year the El Camino has a less noisy exhaust system so I can hear a slight whine from the rear gears.I also changed the cruck from Auto to 4 speed so I might be listening too closely.It comes on about 45 mph and seems to disappear at about 55 mph when the vehicle is accelerated slightly.No noise is heard at steady speed or when coasting.Other than that,it's quiet.
You think I should be concerned? As in pull the cover and check it out ? Or just forget about it. This is not a race car ,has a warmed up 305 with a 4 speed manual.

 

[Toner283]

Unless it gets louder or starts to whine more often I would not worry about it personally. Put a little lucas in it if it worries you. as long as the wear pattern was OK when you put the gears in & you torqued everything you should be fine IMO.

 

[bowtie81]

did you put a rear end conditioner back in it. some need it to take the chatter away, maybe that might help you.

 

[Truckedup]

I put a conditioner in the oil when I did the gears.I followed the break in stuff,drive for a short time,let it cool down then drive for a few hundred miles and drained the gear oil.I used synthetic 75-90 oil after that.

 

[bowtie81]

did you put the conditioner back in after the oil change? when i changed my gears i was told to take it easy for the first 500 miles then beat on it after that but i always put the conditioner in it.

 

[Truckedup]

I didn't use conditioner after changing the oil.I thought the conditioner is for the Posi clutches and the synthetic oil says it's good for posi with no additives needed.

 

[bowtie81]

i dont know on all the synthetic stuff.

 

[Truckedup]

Yes,and maybe I don't know what "chattering" really is.Tight low speed turns coasting or steady power is smooth.But when I turn out of my stone driveway onto the road and accelerate gradually the rear tires chirp a bit.I can feel it when making a tight turn on any loose surface I guess.I'm thinking this is normal posi action?

 

[bowtie81]

it might not be a bad idea to look at how the gears are wearing.

 

[LS6 Tommy]

I put a conditioner in the oil when I did the gears.I followed the break in stuff,drive for a short time,let it cool down then drive for a few hundred miles and drained the gear oil.I used synthetic 75-90 oil after that.

What posi did you use? Both Eaton & Auburn say NOT to use synthetic oil because it messes up the friction materials in the diff, but it shouldn't create gear whine. They usually call for petroleum/mineral based 80W90.

Tommy