Rear end is "whining" under load

I have a really loud drivetrain "whine" coming from the rear of my 2007 with 120k on it. Its whined for years, but I feel like its getting louder now. Its quite overpowering and uncomfortable to drive when at 70mph since its so loud.

Both of my rear wheel bearings have been replaced in the past year because they were grinding, and confirmed bad when we did them.

So I can confirm its not the wheel bearings, and its much louder then them.

To be honest, it sounds like i have performance gears in a manual transmission type of whine, think straight cut gear whine.

Ive read there are a few TSB's for the rear diff, but Im having trouble finding them, this is the only one I could find that calls out the rear baffles.

Anyone give me some help, or point me in the right direction? Starting to think i should have jut gotten an updated rear axle from a wrecked newer tundra.

Oh, and you let off the gas and it goes away. Id say it starts around 50mph and just gets louder the faster you go. Let off the gas, and its silent.

 

Set the rear up on jack stands and have a buddy hit the gas while you listen.

 

Tell it to be quiet or you'll give it something to cry about? Worked for my parents with us kids.

 

Not sure that would do for me? I know it's the rear differential.

 

Dumb question. Have you drained and checked the fluid for metal pieces?

 

Yup, changed its last schedule, then when we did both wheel bearings and its been clear.

 

So do a gear swap.

 

Then what's your question? Rebuild it or buy a new one

 

I’m looking for the TSB information on it as I didn’t want to spend $3000 on a new rear diff.
If the TSB says something makes a sound and is an easy fix, I’d rather do that when I have no evidence the diff has mechanical failure.
Toyota and my local shop said if it’s making a sound, replace the whole thing and it’s $3600 OTD and no one will provide me with any of the TSB information.

The TSB I posted above is about $100 in parts…

I posted this looking for help and direction, not “buy a new rear end and rebuilt it.”

But if I have to spend almost 4k to have a quiet truck then maybe that’s what I need to do.

 

Pinion bearing. If the sound is there when you are in the gas and goes away when you let off it is the pinion bearings. You will have to pull the axles and remove the 3rd member to change them. You could remove it yourself and drop the 3rd member off at a shop that rebuilds rear-ends and save yourself some money.

 

The repair is all labor maybe $100-150 in parts. Replace both pinion bearings and races (I'm sure they are pitted causing the noise) carrier bearings and races install new pinion crush sleave and pinion seal then tighten until correct rotational torque is achieved.

 

What fluid did you use?
I suggest Amsoil I had a 96 Mustang GT that would do this exact things. As a groove had been worn in the gear set from a slight misalignment I presume.
I did not have the money or know how to do a gear swap at the time. Amsoil made it very quiet. It was still there but not very noticeable any longer.

 

When you replaced the rear wheel bearings, were there wear marks on the axle shafts from the baffles? If not, that TSB doesn’t apply.

Chock your wheels, apply the parking brake, and shift to neutral. Then crawl under your truck, and shake the diff input flange. If you feel play (radial and axial, not rotational) then your pinion bearings have lost their preload. Either from wear / spalling, or the drive flange nut is loose.

If you can change rear wheel bearings, you can easily swap a 3rd member. No way, no how would I pay up to $4K.

 

Does it just whine or does it change when you step on the gas pedal vs letting off? Usually problems with the pinion vary in sound depending on the load applied by the engine. The bearings on the pinion are not something you can easily change as you'll most likely have to set up the pinion depth. The differential bearings would be easier to change. It would still require a shop press to do but all you would need to do is set up the backlash (which is pretty easy).

Another option would be to just buy a used carrier. You'll just need to know the gear ratio. They are heavy so shipping would be a little pricey but I've seen them from anywhere from $300 to $1000. Much cheaper than the $3000 to $4000 you're talking about. If you can't do the work yourself it shouldn't cost too much to have a mechanic change the carrier.

 

Im not sure why I never saw the email notifications for these helpful responses.

When we changed the wheel bearings there was no abnormal wear noted. The magnetic plug was also very clean.

When driving the whine starts around 50mph. Its gets louder and is probably the loudest at 55, then quiets down a bit up to 70.


My mechanic said he could rebuild it/fix any issue with it if i bring it to him so guess we will be disassembling the rear end here. Are there any videos on doing this?

Or should I just be buying this and putting it in? Im really confused on how separate components are in the rear pumpkin on these things. Hearing third member, Carrier assembly, etc.
https://www.ebay.com/itm/275166575929?fits=Year:2007|Model:Tundra&epid=666446273

 

The picture in your Flea-bay link is a generic picture of a complete front diff, so that may be adding confusion.

The rear is known by all three terms you mentioned, pumpkin, 3rd member, and carrier. I think this is to help avoid confusion. All bearing preload and gear backlash adjustments are already done when a 3rd member is assembled, so a swap is an easy DIY project.


It unbolts from the axle housing after you remove the axle shafts and driveshaft, and this sketch shows it a bit better. And on that note, you may wish to check pricing with some of the online Toyota parts dealers for a brand-new OEM diff, because that’s a decent price in Canuck bucks if you ask me

https://www.toyotaonlinepartsdepot....MIrpzB37Cy9wIVJj6tBh1mjQBoEAQYAiABEgLXl_D_BwE