better gear oil for rearend or ?

[blazer2007]

I have a 80 chev truck 1/2 ton that I got the rear end rebuilt with new everything. I used Motive 3.42 gears and is non posi.I don,t know if they call them spyder gears. I can hears the gears whirling away,not any bad noise but just a noise that you would expect gears to make. I know some people say motive gears are noisy. Is there a better oil or are they not installed right or that,s the nature of the beast. No real sound deadening in the cab.

[toolboxchev]

You could try a small amount of the Lucas Oil additive, yet be careful of that stuff there is no anti-foam agents in their product.

When your rear diff is spinning at 3 grand you do not want it to be full of foam in there.

It is a good friction modifier and tack additive to keep everything coated in oil. I used it in a smokin ole 350 block once an it did make a difference on how much oil it burned.

[blazer2007]

It also seems to resonate thru the driveshaft,maybe why it seems loud and it,s hot out and have all the windows open

[Captainfab]

Were the gears setup with the correct contact pattern and backlash?

[Ironangel]

New gear sets need a break in period and an oil change after 500 miles. If the new gear set was not set up properly ie backlash, preloads, and pattern checks, it will most likely make noise until it dies. It could live for 100K or shell out in 100 miles. Heres a link to part 1 of diagnosing noise in Randy's Ring & Pinion web site. Go there and at the top of the page is the tech option. https://www.ringpinion.com/Technical...e_(part_1).inc I wouldn't use a crankcase additive in the differential because gear lubes are formulated to resist shear and are rated differently. Since you have an open differential practically any gear lube with a GL-5 rating will work. Synthetic gear lube will resist thermal breakdown better than mineral oils will. There are usually three viscosity ratings available, 75w-90, 80w-90, and 85w-140. You can try the 85-140 but that stuff will be like thick molasses in those Canadian winters. Maybe what a noisy rear end will like...

[Bigdav160]

It is not the spider gears. They are not moving unless you are going around a corner. And even then, they are spinning fairly slowly.

Sounds like someone might not have set the gears up correctly.

[blazer2007]

can the gears be re set or is it too late.

[blazer2007]

they have been in for a year and some

[68gmsee]

My 68 GMC has had a slight drone for many years with no problem. A lot of old trucks used to have either transmission or rear axle drone and ran fine for the lifetime of the vehicle.

In your case I'm fairly sure the wear pattern can be checked by a driveline shop. If it's off they can tell you if they can reset the mesh to decrease the noise. However, be sure it's in fact rear axle noise. I had a vehicle that had a droning noise from the rear and it turned out to be a defective tire.

[blazer2007]

I did put new tires on this spring, I didn,t get the rears balanced as they were so busy with spring tire change over so I put the tires on myself. Thanks I forgot I never balanced them.

[toiletbowl54]

look at Redline Lubricants, not cheap but they make a good product. Another would be Amsoil.