Gear oil vs Gear Lubricant

Boone83K10

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I have two questions...

1. My book says this...

"Drive Axle (Rear and/or Front)
FLUID RECOMMENDATIONS


Front axles use SAE 80W-90, GL-5 Gear Lubricant. Rear axles use SAE 80W-90 gear oil. Positraction or locking axles must use special lubricant available from dealers. If the special fluid is not used, noise, uneven operation, and damage will result. There is also a Positraction additive used to cure noise and slippage. Positraction axles or locking axles have an identifying tag, as well as a warning sticker near the jack or on the rear wheel well."

What is the difference between the gear OIL and gear LUBRICANT. All I ever find at autozone/advanced auto is gear oil and my front diff needs some fluid added and book says gear lubricant.

2. When the truck is cold there is no noise but when it gets down the road a bit, there is a "rubbing/grating" noise. It is not constant,it is cyclical (like with tire rotation, hear it, goes away, hear it, goes away) It goes away totally under 15 mph. It does it with brakes off and on, in 2wd, in 4wd... it does it all the time. WHAT COULD IT BE!!!!!!!!!!!!
 
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MrMarty51

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Pull them covers off them differentials and drain them.There will be some blackish looking crap.Wipe the bottom of the housing with rags.Particularly looking for "CHUNKS" of steel.
Put the covers back on and refill them housings using a "Gear Oil or Gear Lubricant" that says " GL 5 " and You then Mine frien will have the proper stuff,again that is GL 5.I always use the "Full synthetic stuff.Sometimes it will not be 80-90 but more like 75-90 and it is all good.
 

Boone83K10

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Well thanks for that info, I will do front and rear... but I found out the diff isn't making the noise. It's my speedometer cable at the back of the gauge. Dry as a bone! Going to get a new one and put it in.
 

MrMarty51

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Well thanks for that info, I will do front and rear... but I found out the diff isn't making the noise. It's my speedometer cable at the back of the gauge. Dry as a bone! Going to get a new one and put it in.

That can be lubed and reused.
At work We always used 105 assembly lube on them and stuffed them back down the hole.
Now that`ll stir some controversy,when some will say to use only graphite.:yawn:
 

Boone83K10

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lube is lube... if you get my drift:manos:

also, the end of the cable at the transfer case is torn up, you can see exposed wire so it needs to be replaced.
 
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Boone83K10

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I took the old one out and shot some graphite spray I had.. it is quieter now but I still hear it at 15 mph. Think the part it plugs into in the gauge needs some graphite?
 

85 Squarebody76

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That can be lubed and reused.
At work We always used 105 assembly lube on them and stuffed them back down the hole.
Now that`ll stir some controversy,when some will say to use only graphite.:yawn:
I use sewing machine oil... works great and mends your pants while you drive.....
 

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