Rear end howl/whine at 60mph....NO MORE HOWL!! issue solved.....ITS BACK!!!!! :(

pulled the trigger on the ECGS 3rd a few moments ago.....THREE WEEKS to get it!!!!!
(they have approx 50 orders ahead of mine)
I guess I will reinstall driveshaft & squeeze a few more miles out of the howler
I cant live without my taco for 3 weeks

 

So, i put the rear axle on Jack stands, and let it idle in drive. I listened to the diff right behind where the ds connects, both wheel bearings and several places around the 3rd. I didn't hear anything of concern.
The carrier bearing has a fair amount of slop, but haven't scoped it to listen to it. I was doing this alone and really didn't feel comfortable being completely under the truck without anybody in the cab.

 

Man, congratulations on getting 300k out of the original. Did you order a diff with a traction device or open.

 

thanks....Im stilling running the original front shocks & rear brakes too.....crazy huh?
both are due for replacement, but still have a few miles left in em
I want to deal with this howling before I jump into front shocks
plan to replace the rear brakes when swapping out my original 3rd with the ECGS rebuilt unit

I ordered the rebuilt with an open diff....same as my original
I did request the solid pinion spacer instead of the crush spacer

 

when I tested mine, I did it with the truck turned off....removed the driveshaft connection at the rear diff, jacked the rear up & turned the rear wheels by hand (my daughter) & scoped the diff only (I already recently changed both rear wheel bearing, so I know those are good)

I listened at both carriers bearings (that are inside the rear diff) & the pinion bearings at the head of the 3rd member (aka rear diff)
I found a substantial amount of rumbling at the pinion bearing area verses other parts of the diff/rear axle

I would recommend isolating drive train components, then scoping.....those dang sounds/rumbles can transfer easily & confuse the F out of one
I learned this the hard way...hence replacing all my wheel bearing for no reason
(front wheel bearings got replaced with the front diff needle bearing swap out a few months back....I thought I had a bad front wheel bearing, so I replaced it only to find the rumble I was hearing was coming form the front diff specifically the piece-o-crap needle carrier bearing)

when you state 'carrier bearing' I assume you are referring to the rear driveshaft center support bearing (donut)...is that correct?
if so, I looked at mine as well....it has a lot of slop....wondering if this could be an issue or maybe normal? cause strange harmonics?

anyone have suggestions on testing the 'donut' (rear driveshift center support bearing)?
what is normal amount of play/slop in the donut?
maybe someone with a newer/lower mileage taco can get under their rig & check how sloppy theirs is & report back?

 

Changed the front axles, wheel bearings, ecgs bushing already. Figured at 300k it was time to do it anyways.
Yes, I've been calling the center support bearing on the ds the carrier bearing. I also noticed some mechanical play i believe to be in the slip joint behind the middle u joint.
I've got to change the oil and a sway bar link shortly. After I'm done with that, I'll go back to trying to remove the ds.
This would be much easier on a lift. Lol

 

hell ya on the lift buddy....in my perfect world, one day I will have a big ass garage just for tooling (like 30x30)
& an auto lift for these moments in life
I dont mind working on my taco, but I hate laying on the cold garage floor, ready for the warm months right about now

 

a BIG thank you to US Marine for his help/guidance.....cheers!

 

sorry about the typo on the title...I just fixed that...lol

 

Taking it out for a drive as I voice to text. I still have the drone after taking the drive shaft out. I am not happy about this.

Feels weird driving it without the rear wheels pushing it along and there's a bit of torque steer as well that I am not used to.

 

yeah, when I did the remove rear driveshaft & 4hi test, it felt so strange being pulled not pushed & I def felt the steering & engine power interacting (torque steer)

can you describe the 'drone' you are experiencing in more detail?
maybe you should try the opposite test & remove the front drive shaft & road test for any change?

 

It's a sound that gets particularly loud around 60... It starts ramping up around 50, by 70 it's calmed down.
It resonates the the whole cabin and for the life of me can't localize it to any specific area of the truck.

 

I am going to assume you clued into this thread due to the 50-70mph in the title
because the 'noise' that I hear, it very faint & doesnt resonate at all(so faint most would not even notice it until pointed out)
& causes no vibrations inside my cab
furthermore it only occurs on decel between 50-70, most identifiable at 60mph though if demonstrating
it is weird how the noise is not noticeable on decel at speeds above 70 though....
maybe the howl is still there just too much engine/road noise at those speeds

I think we have different issues, particularly because when I removed my driveshaft, the howl vanished
& you had the opposite result...your noise persists with driveshaft removed
at least you know its not your rear end

have you checked your rear wheel bearings? have you replaced them or are they the original ones?

 

The bearings are original. I listened to them when I had it jacked up yesterday. I didn't hear anything that made me say, hmmmm.
I'm not feeling any vibrations either that I could associate the 2 together.
Used a little go pro knock off watching the center support bearing and went for a ride. Aside from is sagging it wasn't shaking or anything.
Moot point though as pulling the drive shaft didn't change anything...

 

bummer on not isolating the issue on your end bud
I cant wait to get my rebuilt 3rd & test
I really want this annoying howl gone so I can get back to driving the crap out of my taco

 

Experiencing same issues at 160k miles. Regularly been changing the oil at 30k too

 

Yes it is.... Life goes on. I'll figure it out.
Good luck with that third. Hope it solves your issue.

 

how long (or for how many miles) have you heard the howl?
do you have metal flakes on diff drain plug (magnet) when you change the fluid?
my howl is very faint & subtle...Ive had many people ride with me & dont notice the howl until I point it out
is yours the same ? very faint & subtle sound around 60mph & ONLY on decel?

have you removed your rear drive shaft, put it in 4hi & test to see if noise disappears?

 

Just wanted to throw this out there... U-joints are known to make howling noises before / during failure.

 

At least 10k miles i think. Drove out to Utah again this past summer. Didnt notice much noise at last diff oil change at 150k miles, but have replaced both front hubs in that time. Also really noticed it once I put a new carrier bearing and ujoints in

On the list to pull the DS and verify before i order a new 3rd.