HELP!! Strange grinding/creaking from front end!!

[Daniel Robertson]

HELP!!!
I joined this thread in search for input on similar cases or possible causes for the issue I am experiencing. Just purchased this perfect yukon with a 6in lift, 35"s, 4.56 front and rears with 66k original miles... this thing is perfect... Tires @30% tread life
Got it home and noticed as I was pulling into the driveway a slight creak in the front left or grind as the car was decelerating under 10mph in 1st and 2nd. The noise only occurs in gear, so it is not present when coasting at similar speeds in neutral. The brakes are good and no abnormalities with those. Does the same noise in 4H and 4L. Took it to a guy at NTB to get it checked out and he said there was nothing wrong with the hub or anything that he could see. He said its a common thing to have a noisy suspension when lifting older chevys.
I figured it was total BS because it didn't occur in neutral. Ive heard everything from tires, bearings, hubs, and ball joints but it seems too much like grinding rather then any of those.

My Guesses:
CV joint (boots are in good shape though)
4 wheel drive actuator sticking
alignment
front differential/ fluid

Anybody encounter this before in your rig??
The sound is similar to bad, grinding breaks but the breaks do not affect the noise in any way. Still makes sound in gear coasting without the brakes and is absent when in neutral.

Thanks for your time!

Dan

 

[Scottydoggs]

come to a firm/hard stop the nose dips as it should, now at full stop let the brake go, does the front come up some after you let the brake go?

if so your hearing brake squawk. its the slipper yolk on the front drive shaft, its dry, gm made sure to not put a grease fitting on it, so you need to take it off the axle pull it open grease the hell out of it and work the shaft in and out till it slides smooth. might even need to clean it first if its caked with old hard dry grease. mine was.

i took my truck in for this sound and nose staying down after a stop to the dealer, they had no f ing clue wtf it was and washed their hands of it.

afterward i found the TSA for it, ( brake squawk) showed it to them after i fixed it and they still claim to have never seen that tsa. good job dummys lol

hope this is your issue cause its pretty simple to fix.

 

[Daniel Robertson]

took it in to a guy that knows just about everything about 4x4s and he was able to diagnose it fairly quick after a test drive and getting under the car to shake the front drive shaft. He said the drive shaft is what he suspected upon driving and after shaking it, he confirmed that it is the front drive shaft for it had quite a bit of play.
NOW...
he sais it is best to just replace the front drive shaft; for the vehicle is lifted with the 4.56 gearing. Is this the route I should take or do you recommend just removing, greasing, more greasing, and see what that gets me?

 

[Scottydoggs]

if its loose at the slipper joint its trash, grease would be a very temp fix.

i'd have to think you have a lengthened shaft for the lift, or its at the very end of the slipper joint. and thats a fast death id think.

 

[Daniel Robertson]

UPDATE!!! I removed the drive shaft (suspected problem) and the grinding noise persists...
I am now almost certain it is the front differential causing the racket under deceleration. I recently engaged 4x4 hi and it was almost siezing up/ under a lot of friction when decelerating and the grinding noise persisted.
Any ideas as to what it could be? I just changed out the front diff fluid and noticed very little metal flaking so that is good, also a small leak at the front passenger cv joint/ front diff connection. any ideas or should I just take it in to a trans shop?

 

[Daniel Robertson]

alright guys I need your experienced opinion on this one... took it in to 4WP and they got it on the lift and was underneath with a stethoscope hearing for strange noises in the drive train and concluded that the noise was spawning from a bad rear end bearing, he wants to do a master kit... MY QUESTION is why would the noise be coming from the front end/ steering column if the rear is making the grinding noise? could the sound be traveling up the drive train?? what do yall think??

 

[iamdub]

Can you reinstall the front dshaft, remove the rear dshaft and drive in 4WD?

When you had it in 4HI and felt the " almost siezing up/ under a lot of friction", were you on pavement?

 

[M1Gunner]

Those 4.56 gears, are they stock? What’s your original gearing rpo code?

 

[Daniel Robertson]

problem solved... rear end master kit fixed the grinding noise, strange how it sounds like it is coming from the front end

 

[M1Gunner]

Nice glad ya got figured out bubba!