Noise from Transfer Case or U-Joint(s)?

[markbarb]

I have a 1999 Yukon with only 65K miles. It's running well, but I started to hear a rhythmic sound while driving.
It is subtle, but I can hear it when I take my foot off the accelerator to quiet the engine.
Sounds like a click each time the wheel rotates so it increases frequency when I accelerate.
It does not sound like a "clunk" to me. I've been ignoring it for a couple of weeks, but I am taking it to the dealer on Monday.
From my reading, this could be a worn u-joint or a failing transfer case.
Any other possible arm-chair diagnoses?
Thank you!

 

[Hoesgottaeat2]

Greetings and welcome from NY!

Are you certain the 4WD isn’t engaged? CV joint or u-joint come to mind first. I’d suggest getting it up in the air and get the drive train spinning and see if you can locate the source of the sound. If you don’t have a lift, your appointment at the shop sounds like your best bet here. Good luck and let us know what you find out.

And let’s see some pics of that ‘99 with only 65k on it!

 

[Fless]

Wheel bearing?

And welcome!

 

[ivin74]

And let’s see some pics of that ‘99 with only 65k on it!

X2

 

[YukonGTmaster]

Whenever my U joints have gone bad, I have either got a squeaking sound, a vibration with speed, or a clunk when putting it into reverse.

With that low mileage, I would think the CV's would be good unless the rubber boot is damaged.

Post up some pics, and let us know what the mechanic found if you can!

 

[Hoesgottaeat2]

Whenever my U joints have gone bad, I have either got a squeaking sound, a vibration with speed, or a clunk when putting it into reverse.

With that low mileage, I would think the CV's would be good unless the rubber boot is damaged.

X2

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

 

[markbarb]

Greetings and welcome from NY!

Are you certain the 4WD isn’t engaged? CV joint or u-joint come to mind first. I’d suggest getting it up in the air and get the drive train spinning and see if you can locate the source of the sound. If you don’t have a lift, your appointment at the shop sounds like your best bet here. Good luck and let us know what you find out.

And let’s see some pics of that ‘99 with only 65k on it!

Thanks for the reply! I'll get some photos soon, and let you know.

 

[markbarb]

I ended up taking my 1999 Yukon with 65K miled to the dealer and to a local mechanic.
Neither mechanic could hear the sound I was talking about at first.
So I went on test-drives with each of them and pointed out the subtle sound I heard.
I had both of them put it up on the rack and listen with a stethoscope, and they both heard sounds in the transfer case.
Dealer quoted about $4000 to repair with new parts (although some parts are no longer produced).
The independant mechanic said he only heard the transfer case noise in 4WD.
He said it could be from the tires, which are worn, or perhaps valve lifter noise.
He advised no repair at this time but monitor the sound, since I do not drive it in 4WD.
My plan is to get new tires first and see what I hear.
Here are some pictures.