Do yukon gears quiet down post break in?

[CptFloridaMan]

Just got the jeep regeared to 4.56 and had them throw a locker in the rear. But on decel around 20-30mph it’s a very quiet whine that you almost don’t notice unless you listen for. I’ve read online once upon a time that some whine goes away after the new oil goes in.

Aside from that the 4.56 transformed the jeep.

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[dstevens]

When I did 4.56 Yukons on my JK they never made any noise at any time or any condition. But then I did the re-gear myself, took my time and got the lash, bearing preload and pattern as close to perfect as I could.

I'd get the back lash and pattern re-checked. And I'd find what the lash numbers are and get photos of the pattern. If something is wrong you want to catch it before it wears the gears. And checking backlash is very easy, and the pattern not too bad to do, but you need to have done it before.

 

[wibornz]

I would not think that it will improve, I think it will get worse. I would take it back and complain. It sounds like the back lash is not correct.

 

[conFUcius]

@chevymitchell

 

[wibornz]

@chevymitchell

@chevymitchell will probably give you the best advice. He is on point with gearing and Jeep things in general.

 

[chevymitchell]

Just got the jeep regeared to 4.56 and had them throw a locker in the rear. But on decel around 20-30mph it’s a very quiet whine that you almost don’t notice unless you listen for. I’ve read online once upon a time that some whine goes away after the new oil goes in.

Aside from that the 4.56 transformed the jeep.

Your gears shouldn't make any noise. If they do, then they need to be inspected or adjusted. It's normally a very simple fix; a little more or less shim on the pinion and then a proportional amount of change on the carrier.

With that said, what you're experiencing isn't uncommon. For it to whine on decel at that speed, it's likely a .002-.005" difference in the pinion. This would be hard to detect on the test drive, too, so don't hold the installer to the fire quite yet. Always give them a chance to make it right. Now if they were howling and you have broken teeth, don't go back to them. Find someone else, but if it's a little whine at that speed, they'll make it right, I'm sure.

Again, common issue. You'll be good to go once they get back in there. Just sucks for them because now you'll need a new crush sleeve and they get to do it for free fitty. Lol.

Ask them to double check the front, too, on the next test drive just to cover your bases.

 

[CreepyCrepe]

I would not think that it will improve, I think it will get worse. I would take it back and complain. It sounds like the back lash is not correct.

Should his whine be proportional in volume and tone to the diff whine? ?

 

[CptFloridaMan]

Your gears shouldn't make any noise. If they do, then they need to be inspected or adjusted. It's normally a very simple fix; a little more or less shim on the pinion and then a proportional amount of change on the carrier.

With that said, what you're experiencing isn't uncommon. For it to whine on decel at that speed, it's likely a .002-.005" difference in the pinion. This would be hard to detect on the test drive, too, so don't hold the installer to the fire quite yet. Always give them a chance to make it right. Now if they were howling and you have broken teeth, don't go back to them. Find someone else, but if it's a little whine at that speed, they'll make it right, I'm sure.

Again, common issue. You'll be good to go once they get back in there. Just sucks for them because now you'll need a new crush sleeve and they get to do it for free fitty. Lol.

Ask them to double check the front, too, on the next test drive just to cover your bases.

Great info thank you. Yeah no i’m not gonna hold them to a fire yet, if anything he said he’d warranty it so there’s at least that. It’s also hard to hear over wind and tire noise. I’m going to spend some time driving it around today and listen for it also.

Should I wait for break in to go back there and have him take a look at it? And for the front, should I throw it into 4hi every once in a while? Cause from what I understand the driveshaft doesn’t rotate when it’s in 2wd.

 

[chevymitchell]

Great info thank you. Yeah no i’m not gonna hold them to a fire yet, if anything he said he’d warranty it so there’s at least that. It’s also hard to hear over wind and tire noise. I’m going to spend some time driving it around today and listen for it also.

Should I wait for break in to go back there and have him take a look at it? And for the front, should I throw it into 4hi every once in a while? Cause from what I understand the driveshaft doesn’t rotate when it’s in 2wd.

Don't wait until the break-in because once they reset the gears, then the new mesh will require a little bit of breakin. Earlier you can get in there, the better it will be for the gearset.

Yeah, definitely throw it into 4HI from time to time on straight roads only, of course, and at slower speeds. Don't forget to put the Jeep into reverse in 4HI, as well, to make sure you don't have any pinion preload issues.

You got to remember that the torque required to move the ring gear comes from the pinion literally trying to unscrew itself from the ring gear. So total preload set during install is great, but is usually only tested in one direction; FWD. I always check reverse with the front diff in 4HI since it never gets checked or tested until you're off road or in the snow.

 

[azwjowner]

Your gears shouldn't make any noise. If they do, then they need to be inspected or adjusted. It's normally a very simple fix; a little more or less shim on the pinion and then a proportional amount of change on the carrier.

With that said, what you're experiencing isn't uncommon. For it to whine on decel at that speed, it's likely a .002-.005" difference in the pinion. This would be hard to detect on the test drive, too, so don't hold the installer to the fire quite yet. Always give them a chance to make it right. Now if they were howling and you have broken teeth, don't go back to them. Find someone else, but if it's a little whine at that speed, they'll make it right, I'm sure.

Again, common issue. You'll be good to go once they get back in there. Just sucks for them because now you'll need a new crush sleeve and they get to do it for free fitty. Lol.

Ask them to double check the front, too, on the next test drive just to cover your bases.

And by "isn't uncommon," I assume sometimes Dana screws up from the factory because my 2022 with 4500 miles has been whining since new on decel but only when above 60+ mph. But I'm going to regear in a month, so I let it be.

 

[chevymitchell]

And by "isn't uncommon," I assume sometimes Dana screws up from the factory because my 2022 with 4500 miles has been whining since new on decel but only when above 60+ mph. But I'm going to regear in a month, so I let it be.

Correct, but it's incredibly rare.

 

[word302]

Honestly some aftermarket gears will whine even if setup perfectly. Yukon has had terrible quality control for several years now. I don’t recommend Yukon gears to anyone and know several gear specialists who won’t use them anymore.

 

[John Benoit]

Just got the jeep regeared to 4.56 and had them throw a locker in the rear. But on decel around 20-30mph it’s a very quiet whine that you almost don’t notice unless you listen for. I’ve read online once upon a time that some whine goes away after the new oil goes in.

Aside from that the 4.56 transformed the jeep.

If you have whine, the gears are not set right.

 

[Steph1]

I had my Jeep regeared with Yukon 4.56 gears 2.5 years ago and remember a whine that lasted 2 days and then completely disappeared.

 

[wibornz]

Should his whine be proportional in volume and tone to the diff whine? ?

Mine whine would be louder than the diff whine. A re-gear is expensive. when a shop makes a mistake, it is not a cheap fix. As the shop has to buy another install kit to correct the problem. Then of course if the gears are already worn in to a bad pattern, they will probably have to install new gears.

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