One thing that is interesting is that the chain drive and the front drive shaft are connected and always spin together, but they should not spin at all when traveling in two-wheel drive (or sometimes they will very slowly creep for reasons that would take too long to describe here). Yet on this truck, it seems that the chain drive is spinning even when the vehicle is in two-wheel drive. This could be due to the "front-axle disconnect" mechanism not disengaging like it's supposed to, or it could be that a faulty shift mechanism in the transfer case is keeping it in four-wheel drive at all times. You would expect to recognize that second possibility right away during the test drive, but not if the front axle is disengaged like it's supposed to be, which is certainly possible since that part could be working properly even if the main shift mechanism is not. I hope you are able to report what is going on here. In any case, failure of the chain drive to fully disconnect when in two-wheel drive will lead to premature wear of the chain (of course, the chain might have worn out from lots of 4x4 use in a vehicle that has that many miles).
Im having a similar problem but my case is that it only makes the clunking noise while in 4wd. However 2wd drives perfectly fine, could it be the transfer case like the video ?
My 2001 tahoe sits at 450,000 mileage and suddenly im getting all sorts of ailments. hub bearing, cv axle, front diff, and now i think its the transfer case. Theres a rattling coming from the driverside. It sounds like a metal fan brushing up against something as i pick up speed and even when slowing down the sound begins to slow down too.
Note to self: It's not unheard of to cut an exhaust piece out of the way and then weld it back on later to get a transmission out. Not a recommended procedure.
I just saw this video and wanted to ask a question. I have a 2001 Chevy Suburban 1500 2 wheel drive. No 4 wheel drive option. It has over 300,000 and has been running fine. However, about a month ago, it started to make a grinding kind of noise at highway speeds. It doesn't make the noise below 50 mph and when it makes the noise, it comes and goes. My mechanic can not seem to find out what's making the noise. With your knowledge, do you have any idea what might be making this noise when it goes above 55 mph? Anything you could think of would be greatly appreciated. Thank you for your time.
Nice. I wish you were near me. My 02 suburban is making a weird noise almost like card in a bicycle spoke but I only hear it at low speed when coming to a stop sign or light. It's not brakes because it happens without braking. I'm gonna change the ujoints to see if that fixes it.
Mines doing the same thing. It starts from a low speed. Right at 10mph. Then stops after. Sounds like a fast flappy kind of almost grind. But doesn’t sound like metal grinding.
Same problem, thought it’d be the axles changed those, it helped a bit to reduce the sound, then changed the whole front end suspension except for the lower control arms & that helped more but I still have that sound, happens at 7-10 mph.
My best friend is a retired 30 year GM dealer tech. My '01 is doing what you are describing. He said there is a clip in the transfer case that breaks and usually knocks out a hole in the case. Sometimes hole can be welded, sometimes it can't. Hoping he can weld it. Haven't crawled under it yet to see. He said it's a matter of replacing the clip and hopefully welding it or buying 1/2 the case/cover as they are 2 pieces bolted together.
Great tip for the exhaust.
99 through 06 were the best GM trucks and suvs are the best gm made.
I agree 👍
This would be fun to explore inside. The 246d case of this vintage was prone to pump rub, so the seeping could be more serious than meets the eye.
If we get the job. I will be disassembling it to see what happened . I know the cases are known for cracking as well
Thank you so much. My truck is making this exact same sound
You're welcome! Glad I could help. Thanks for watching!
Mine is making the same noise after rebuilding my 4l80 at the shop 1hr later down the freeway clunking noise slapping my foot underneath
there was that cir clip that wears through the case rear right side maybe it snaped
Do you know if a transfer case control module has to be programmed after installed on a 2006 avalanche 5.3 liter.
Yep, sounds like the transfer case. Thats pretty good for 300k, sounds like a flapping chain
One thing that is interesting is that the chain drive and the front drive shaft are connected and always spin together, but they should not spin at all when traveling in two-wheel drive (or sometimes they will very slowly creep for reasons that would take too long to describe here). Yet on this truck, it seems that the chain drive is spinning even when the vehicle is in two-wheel drive. This could be due to the "front-axle disconnect" mechanism not disengaging like it's supposed to, or it could be that a faulty shift mechanism in the transfer case is keeping it in four-wheel drive at all times. You would expect to recognize that second possibility right away during the test drive, but not if the front axle is disengaged like it's supposed to be, which is certainly possible since that part could be working properly even if the main shift mechanism is not. I hope you are able to report what is going on here. In any case, failure of the chain drive to fully disconnect when in two-wheel drive will lead to premature wear of the chain (of course, the chain might have worn out from lots of 4x4 use in a vehicle that has that many miles).
Im having a similar problem but my case is that it only makes the clunking noise while in 4wd. However 2wd drives perfectly fine, could it be the transfer case like the video ?
My 2001 tahoe sits at 450,000 mileage and suddenly im getting all sorts of ailments. hub bearing, cv axle, front diff, and now i think its the transfer case. Theres a rattling coming from the driverside. It sounds like a metal fan brushing up against something as i pick up speed and even when slowing down the sound begins to slow down too.
I am dealing with the same problem now on my 01 suburban
Same here 98 GMC suburban
Note to self: It's not unheard of to cut an exhaust piece out of the way and then weld it back on later to get a transmission out. Not a recommended procedure.
How much is the repair tho?
Mine doing the same thing as we speak but mine also want engage in park and when put in reverse it just sits there and grinds terribly
I just saw this video and wanted to ask a question. I have a 2001 Chevy Suburban 1500 2 wheel drive. No 4 wheel drive option. It has over 300,000 and has been running fine. However, about a month ago, it started to make a grinding kind of noise at highway speeds. It doesn't make the noise below 50 mph and when it makes the noise, it comes and goes. My mechanic can not seem to find out what's making the noise. With your knowledge, do you have any idea what might be making this noise when it goes above 55 mph? Anything you could think of would be greatly appreciated. Thank you for your time.
Carrier bearing or rear diff.
My suburban has 413k runs perfect
Can anyone please give me an idea of how long it can be driven in this condition?
Till it stops moving
@@salemgraham9785 GREAT ANSWER!!!! LOL It has stopped moving now! lol
Nice. I wish you were near me. My 02 suburban is making a weird noise almost like card in a bicycle spoke but I only hear it at low speed when coming to a stop sign or light. It's not brakes because it happens without braking. I'm gonna change the ujoints to see if that fixes it.
Mines doing the same thing. It starts from a low speed. Right at 10mph. Then stops after. Sounds like a fast flappy kind of almost grind. But doesn’t sound like metal grinding.
Same problem, thought it’d be the axles changed those, it helped a bit to reduce the sound, then changed the whole front end suspension except for the lower control arms & that helped more but I still have that sound, happens at 7-10 mph.
Definitely check the fluid on the transfer case
My best friend is a retired 30 year GM dealer tech. My '01 is doing what you are describing. He said there is a clip in the transfer case that breaks and usually knocks out a hole in the case. Sometimes hole can be welded, sometimes it can't. Hoping he can weld it. Haven't crawled under it yet to see. He said it's a matter of replacing the clip and hopefully welding it or buying 1/2 the case/cover as they are 2 pieces bolted together.
Can I drop my Yukon off
It was probably a down south mechanic