Clunk in drive line?

[JL724877]

I posted this in another thread but wasn’t getting much traction.

I have been working on fixing everything I can on my 2017 1500 hemi. The next project on the list is to try to figure out what is causing my clunking sound and try to eliminate it. It started very early on in my trucks life like maybe 30,000 miles the truck now has 150,000. To me the sound seems to be coming from the middle or back of the drive line. It started as a clunk that would happen when the the transmission would down shift from 5th to 4th when coasting with foot off gas pedal then when I would hit the gas it would give a slight clunk it did this very infrequently in the beginning. Moving to current noise (I know I should have fixed a long time ago but here we are). I brought it into a Firestone maybe 40,000 miles ago and the best they could come up with was probably something in rear differential backlash or something else. I have changed the rear differential fluid maybe 10,000 miles ago and did not see any metal. Now the clunk is much louder and occurs much more frequently especially when the transmission down shifts from 5th to 4th. It also clunks in other gears occasionally but mostly 4th and 5th usually around 30mph. Also very infrequent a slight clunk at highway speeds. My best guess is it’s a drive shaft/u joint issue or read differential. I tried moving the driveshaft while in neutral and the rear wheels off the ground. It was making a similar sound when the wheels were spinning. When trying to push the driveshaft up and down it didn’t really have noticeable play to me but when rotating it you could move it maybe 1/4 inch without it turning if that makes sense. Essentially it felt like it had some wiggle in it before it’s engaging? Not sure if it’s supposed to have these noises when wiggling it but I will attach some videos for reference. The clunk is definitely getting worse and starting to produce more of a shimmy in the driveline if that makes sense like you can feel it more than before. Please review videos and let me know if this is normal stuff or where I should start. I think I could do the u joints myself and would love for this to be the easy solution but don’t want to tear it out and it be something else. Please help??

I also can’t currently figure out how to post the videos so help with that would also be awesome.

Hope these work.

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View, organize, and share photos and videos with iCloud Photos on the web. Changes will sync across your devices with iCloud.
share.icloud.com

iCloud Photos - Apple iCloud​

View, organize, and share photos and videos with iCloud Photos on the web. Changes will sync across your devices with iCloud.
share.icloud.com

iCloud Photos - Apple iCloud​

View, organize, and share photos and videos with iCloud Photos on the web. Changes will sync across your devices with iCloud.
share.icloud.com

 

[ppine]

U joints are the first place to look.

 

[Grams]

I do not See any play in the u-joints…and it’s difficult in a video to distinguish the direction from which the “clunk” is coming…. But if you want to further eliminate U-joints then grab the SHAFT-side of the U-joint on the driveshaft…and hold the other side of the U-joint and twist the shaft back/forth …to determine if any “play” exists WITHIN each U-joint…. (instead of using the driveshaft to move the entire driveline.)

It appears to Me that the “play” largely exists in the differential, probably between the pinion and the ring-gear.
If abnormal wear has caused this….It usually results in a “whine” either when accelerating or decelerating.

One further check: Grab the pinion-gear immediately Aft of the rear uU-joint…and attempt to dislodge it UP and DN…. carefully observing if any up/dn movement can be detected of the pinion. ( I beleve you will find none exists because I see no evidence of pinion-seal leakage.)

If no “whine” exists, especially when accelerating or decelerating…. then Live with it as a normal result of normal wear. Avoid letting your notice of it becoming an irritation that performs no useful function of diagnosis. (If correct, it will perform no useful function to readjust pinion-gear depth on the ring-gear…. AND …it Might create a new area of wear on the differential gears after you’ve adjusted it away from where those gears have “broken in” to each other.

My conclusion: You have no serious problem.
My opinion is worth what you paid for it… but I was the Only Factory Trained rear axle specialist at Palm Center Toyota in Houston and my main job was detecting and solving rear axle and differential problems.

 

[TC]

Control arms good and tight?

 

[Curmudgeon]

@JL724877

First: I am not any kind of auto mechanic, never have been, other than to do the kinds of "backyard" things I could easily do, brakes, alternator, water pump, starter, etc., going back to the early 1970's.

Second: However I have had a decades-long career of working with my hands, electro-mechanical and such. I have a strong appreciation for logical troubleshooting and thought processes.

Watching your videos, I want to remove the driveshaft and rear u-joint and try the same twisting test on just the pinion shaft (is that even the word?) to isolate the differential as being either "it" or "not it". Then go from there, however, I don't see any play between the rear u-joint and the pinion shaft, and both are moving together, leading me to believe the play, and the clunk, are in the diff.

If it helps, I just walked out to my truck, and with all 4 wheels on the ground I
grabbed my driveshaft and tried your twist test, and I got ZERO movement, ZERO clunking, it is really tight. And I don't have any clunking either.

My 2014 1500 118,000 miles has never towed and only ever hauled a 5-foot bed of firewood, so mostly a grocery-getter.

While I can see how excessive diff wear would cause a whine, what you have still does not look right to me. I would keep looking. But that's just me.

Also, I have had my rear diff lube changed out once before, at the stealership. I don't recall exactly when or what mileage, but if it matters I do still have the receipt buried in my files. Everything about my truck is exactly as it came from the factory, as in, no mods except a oil catch-can, and normal upkeep: fluid changes, tires, brakes, etc.
Hope this helps.

 

[JL724877]

I do not See any play in the u-joints…and it’s difficult in a video to distinguish the direction from which the “clunk” is coming…. But if you want to further eliminate U-joints then grab the SHAFT-side of the U-joint on the driveshaft…and hold the other side of the U-joint and twist the shaft back/forth …to determine if any “play” exists WITHIN each U-joint…. (instead of using the driveshaft to move the entire driveline.)

It appears to Me that the “play” largely exists in the differential, probably between the pinion and the ring-gear.
If abnormal wear has caused this….It usually results in a “whine” either when accelerating or decelerating.

One further check: Grab the pinion-gear immediately Aft of the rear uU-joint…and attempt to dislodge it UP and DN…. carefully observing if any up/dn movement can be detected of the pinion. ( I beleve you will find none exists because I see no evidence of pinion-seal leakage.)

If no “whine” exists, especially when accelerating or decelerating…. then Live with it as a normal result of normal wear. Avoid letting your notice of it becoming an irritation that performs no useful function of diagnosis. (If correct, it will perform no useful function to readjust pinion-gear depth on the ring-gear…. AND …it Might create a new area of wear on the differential gears after you’ve adjusted it away from where those gears have “broken in” to each other.

My conclusion: You have no serious problem.
My opinion is worth what you paid for it… but I was the Only Factory Trained rear axle specialist at Palm Center Toyota in Houston and my main job was detecting and solving rear axle and differential problems.

Thanks for the input!

 

[JL724877]

@JL724877

First: I am not any kind of auto mechanic, never have been, other than to do the kinds of "backyard" things I could easily do, brakes, alternator, water pump, starter, etc., going back to the early 1970's.

Second: However I have had a decades-long career of working with my hands, electro-mechanical and such. I have a strong appreciation for logical troubleshooting and thought processes.

Watching your videos, I want to remove the driveshaft and rear u-joint and try the same twisting test on just the pinion shaft (is that even the word?) to isolate the differential as being either "it" or "not it". Then go from there, however, I don't see any play between the rear u-joint and the pinion shaft, and both are moving together, leading me to believe the play, and the clunk, are in the diff.

If it helps, I just walked out to my truck, and with all 4 wheels on the ground I
grabbed my driveshaft and tried your twist test, and I got ZERO movement, ZERO clunking, it is really tight. And I don't have any clunking either.

My 2014 1500 118,000 miles has never towed and only ever hauled a 5-foot bed of firewood, so mostly a grocery-getter.

While I can see how excessive diff wear would cause a whine, what you have still does not look right to me. I would keep looking. But that's just me.

Also, I have had my rear diff lube changed out once before, at the stealership. I don't recall exactly when or what mileage, but if it matters I do still have the receipt buried in my files. Everything about my truck is exactly as it came from the factory, as in, no mods except a oil catch-can, and normal upkeep: fluid changes, tires, brakes, etc.
Hope this helps.

Thanks!

 

[QwikKota]

Mine has a clunk at take off from a stop. If I let off the brake and let the truck idle forward then hit the gas, the clunk is not present or is very minimal. Hoping it is a U-joint. I think there are at least 2 on my driveshaft that has the pillow block bearing setup.