Whine coming from rear.

Hey guys. I made a post about this a few weeks back. I have a slight whine around 55-60mph sounds like it come from the rear. I’ve taken it to the dealership and they said it’s normal. I’ve also seen a lot of threads with this problem. Other than that noise there is nothing else going on. Can someone give me some advice for this?

 

Really hope it it’s not an axle or pinion bearing

 

Mine kind of crept up on me and someone said what the hell is that grinding/whining noise so at 115k had the local driveline shop look at my Tacoma and it was the rear end needing a rebuild, replace the rear wheel bearings, and also one of the front wheel bearings was shot so did both. Quiet as new after that. I was towing a 26' travel trailer up at the 6500lb limit and that ate the rear. Got rid of the heavy trailer but still tow a 3500lb boat but no problems with that (yet). Lots of threads on where to buy rebuilt rears or DIY but too much time and effort for old me in hot FL. With new front driveshaft u-joints/balance (have TW rear shaft all OK) and all fluids changed all cases it was $1800.

 

my 15 has a slight diff howl/whine right around 60ish. I have the feather the throttle just right and it will do it. Doesn't do it while slowing down and it doesn't do it by accelerating. From what I've read its a harmonics thing. Tons of people have had their diff replaced and it the noise it still there. I had a 3rd gen loaner for a bit a few months ago. It made almost the exact same noise.

My truck has 67k now and It did it when I bought it at 55k. 2015 trd sport. I had the dealer change the rear diff fluid and it didn't change anything.

 

A high pitch whine on Decel is from a bad pinion bearing or loss of pinion bearing preload from a loose pinion shaft nut

A high pitch whine on accel or steady speed is from a bad pinion bearing

A low pitch rumble at speed is a bad carrier bearing

 

What is it when the rear end is unloaded(like feathering the throttle) at 60mph and the whine starts to become apparent. Doesn't it do it on deceleration or acceleration.

 

A worn ring and Pinion gear can do this if the contact patch between both becomes excessive

 

What about on new tacomas or low mileage ones like mine?

https://www.tacomaworld.com/threads...oise-howling-when-feathering-throttle.442341/

 

The Ring and Pinion gears today are mfg'd of very soft metal that isn't properly heat treated which causes abnormal wear patterns which create noise due to excessive backlash . An aftermarket gear set is a much better design than OEM with properly heat and chryrogenically treated gears for closer tolerances

 

This is my very expensive Ford 9" center section for my Camaro . The gears are a High Performance Pro gear , notice the contact patch in the yellow grease

That is a perfect pattern and to make sure the gears are properly broken in it requires a break in procedure

10 -15 minutes of driving gently followed by 45 minutes of cool down

Repeat 5x's

 

If you are interested, Zuk's is a good resource to learn more about Toyota diffs:

http://gearinstalls.com/

Also check out East Coast Gear Supply if you are in the need of a new 3rd member.

https://eastcoastgearsupply.com/

I have heard good things about both, but don't have any personal experience.