Rear end clunk

[BowDown]

Thanks for the photo. There's another end to the splines off the right side of the photo that might also be of interest. But what I notice on this end is.

It looks like the splines are chamfered significantly in a radial direction, but not at all circumferential (which would bear the transmission torque load). So the spline shoulders could be plowing a bit of a ridge into the corresponding splines inside the mating part.

Also, I see some circumferential marks near the left end, and I can't tell if they are just machining marks, or wear marks from contact with something inside the mating part.

So these are clues, maybe, and the other end of this spline may have clues, and of course the mating part (which will be harder to image) may have clues.

I think the problem lies in the end of the shaft, during suspension travel that section is expanding and contracting and when you come to a stop, it binds up on the end if its needing to contract/retract into the female end of the shaft. I think you're right though as that female end may show significantly more wear. If the weather cooperates this weekend, I'm going to take mine apart to regrease it and I'm going to look at the female end of this 2 piece rear section.

 

[Eighty]

Thanks for the photo. There's another end to the splines off the right side of the photo that might also be of interest. But what I notice on this end is.

It looks like the splines are chamfered significantly in a radial direction, but not at all circumferential (which would bear the transmission torque load). So the spline shoulders could be plowing a bit of a ridge into the corresponding splines inside the mating part.

Also, I see some circumferential marks near the left end, and I can't tell if they are just machining marks, or wear marks from contact with something inside the mating part.

So these are clues, maybe, and the other end of this spline may have clues, and of course the mating part (which will be harder to image) may have clues.

One hypothesis on the TRX forum is that the splines are passing past the interior end of the female splines, and getting scored in the process. I can't confirm this theory either way, as I haven't taken mine off. I don't even know if there is an unsplined cavity in the deep end of the female side. But either way, this is supposedly hard steel jaggedness (not grease residue).

 

[Eighty]

The only other option I've found is this but I'm not ready to go this route yet plus I'm not sure this is for the DT

2020 Dodge Ram 1500 Drive Shaft - SKU 348840 - Free Shipping

2020 Dodge Ram 1500 Drive shaft, replaceable u-joints installed. Quality OEM fitment new driveshaft with warranty, fits 2020 Dodge Ram 1500 SKU 348840.

driveshaftstore.com

The only other option is having the driveshaftshop.com make me one with a slip yoke but again, not ready to spend that kinda change on this vs regreasing it every 20-25k miles

I don't know what a peasant DT driveshaft looks like, but here's a picture of a TRX driveshaft.

 

[BowDown]

One hypothesis on the TRX forum is that the splines are passing past the interior end of the female splines, and getting scored in the process. I can't confirm this theory either way, as I haven't taken mine off. I don't even know if there is an unsplined cavity in the deep end of the female side. But either way, this is supposedly hard steel jaggedness (not grease residue).

View attachment 139508

That one is most definitely worn worse and differently than mine. The female side of the shaft is splined about 24-30" up the shaft from what I remember, slightly more than the male side of the shaft

 

[BowDown]

I don't know what a peasant DT driveshaft looks like, but here's a picture of a TRX driveshaft.

View attachment 139509

I'm guessing that shaft comes off the transfer case directly to the rear axle? I've seen some 19's with a similar rear shaft
The regular trucks (4x2) have a 3 piece shaft, some of the earlier 19's have a 2 piece similar to what you have there but here's peasant truck shaft.
Below is the 2 piece rear section of a 4x2 truck, I think the 4x4's have a similar shaft, just shorter


The areas circled in red are where the shaft telescopes.
This is the splined section, it's 3" in diameter. This shaft may also be specific to limited due to the air ride so the shaft length would need to change according to ride height. Either way, there's an obvious greasing/lubrication issue with the shaft



The TRX shaft looks like its about 1.5" yoke shaft that splines into the drive shaft, definitely different that the other trucks

 

[ram0686]

Been having a bump at random stop and acceleration points. This is my driveshaft at 51,000 miles.
Used Red line grease and assembled back together.

 

[ayoslickxd]

i get a clunk shifting into gear usually on slight incline or decline is this normal ?

 

[ram0686]

i get a clunk shifting into gear usually on slight incline or decline is this normal ?

I believe that is normal

 

[BowDown]

i get a clunk shifting into gear usually on slight incline or decline is this normal ?

Set your e-brake while still in gear then put the trans in park

 

[Jordan2929]

I have a single piece aluminum drive shaft and I've had the clunk for about 30,000 miles. Every few thousand miles I would remove the driveshafe and grease the slip yoke for the splines on the transfer case-to-driveshaft connection using the ford XG-8 PTFE grease. The clunk would become much more mild for about a week or two, but always come back. I eventually got annoyed enough, and had enough passengers say "whats wrong with your truck" to do something serious about the issue, I know where the issue is, but I just don't understand why it keeps coming back.

These new rams come with the 5-link rear end which means they "wrap" on acceleration and braking much less than a leaf spring truck. Meaning they don't need as much room for the driveshaft to slide in and out of the transfer case, and when they do, it's a much quicker jolt to the splines causing more friction in a smaller area, not to mention I believe the output shaft diameter for the transfer case is too small. I also believe the output shaft is much harder than the driveshaft yoke, but there's not much I can do about that. All of this together is causing galling on the spline mating surfaces, which then leads to excessive friction on the shaft and yoke. Thus causing the torque coming out of the transfer case to lock the splines together, until the weight and acceleration of the truck moving forward (or backwards) causes the driveshaft to overcome the friction between the splines creating a loud pop or clunk noise..... or so I thought....

Now, when I opened up the transfer case to inspect for further issues I noticed how much play the output shaft had moving in and out (about 3/8") which is exactly where the noise is coming from. The splines are in fact locking together under friction, but the noise (or most of it) is actually coming from the output shaft moving forward and backward inside the transfer case. But when I manually moved the transfer case into 4wd it caused the shaft to have much less play (‹1/8") which made sense because I noticed the clunk much less when I was in 4wd.

So my solution was to use valve lapping compound to "mate" the output shaft and slip yoke together, carefully marking which orientation they were so I could install it the same way after lapping. After lapping the splines for about 1 minute I carefully cleaned all of the very abrasive compound out of the splines which took about half an hour and alot of rags. Then assembled the transfer case and added fluid. I then applied the ford spline grease to the driveshaft splines only, generously covering all the splines. Next, I Installed the driveshaft, being careful to make sure it splined together the same way I lapped it earlier, and manually worked the yoke in and out a couple inches to make sure the grease got in all of the grooves. And when I went to test drive it it was completely silent, which it hasn't been in over 30,000 miles. Only time will tell how long this works... But, if it does comes back, I know I'll be installing a new output shaft and driveshaft yoke.

 

[tim5779]

Apologies gentleman, I've been researching this famous "clunk" for quite some time. I'm hearing several fixes. The most popular is greasing the drive shaft. What I haven't heard, is if RAM has come up with a solution. If not, do they plan to? Basically, what the hell are they doing to fix this, or are we on our own?

 

[Eighty]

Apologies gentleman, I've been researching this famous "clunk" for quite some time. I'm hearing several fixes. The most popular is greasing the drive shaft. What I haven't heard, is if RAM has come up with a solution. If not, do they plan to? Basically, what the hell are they doing to fix this, or are we on our own?

For the TRX, Ram's solution is to simply grease the splines and send you on your way. There's a TSB for it.

 

[Rick3478]

Now, when I opened up the transfer case to inspect for further issues I noticed how much play the output shaft had moving in and out (about 3/8") which is exactly where the noise is coming from.

That sounds excessive. I guess it's not a critical thing, if the internals are still free to line up like they need to, but I'd have thought it would be tighter than that. Anyone know if that's normal? Or might some shims be in order?

 

[Trivisonnom]

I have a 19 Limited that has developed a “clunk” in the rear end. When driving and coming to a stop, I get a clunk almost like a bad joint or a brake caliber sticking and releasing. I heard there was an issue with driveshafts but the search did not bring up anything. Does not feel like transmission but from the rear of the truck. Anyone else have this going on!


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My 2020 Rebel developed a clunk when I would take off intermittently during a trip I took yesterday. Re-torque all the track bar bolts. It fixed the problem for me.

 

[jwtiger69]

I thought I was crazy until I started reading this thread. My 2020 1500 has a similar issue. Hard stops or sudden acceleration from stops I get a clunking sound just like everyone is experiencing. Guess I need to make a call and set up an appointment.

 

[bosco88]

Hello. I have a 2021 Big Horn (4x2). I bought it about a month ago and getting the clunk (sigh). 2 different dealerships would only do the software upgrade - with no improvement. I have a local mechanic that is willing to regrease the drive shaft for me, but I'm unsure which specific lube to use. There are a lot of different opinions/preferences about which is best for this (moly, lithium, PTFE, etc). Is there a general consensus on which is best for this fix (both effective and yields long term results)? And will any CV boot clamp work? Or is there a specific one needed? Amazon perhaps? Thanks in advance.

 

[My1stHemi]

Hello. I have a 2021 Big Horn (4x2). I bought it about a month ago and getting the clunk (sigh). 2 different dealerships would only do the software upgrade - with no improvement. I have a local mechanic that is willing to regrease the drive shaft for me, but I'm unsure which specific lube to use. There are a lot of different opinions/preferences about which is best for this (moly, lithium, PTFE, etc). Is there a general consensus on which is best for this fix (both effective and yields long term results)? And will any CV boot clamp work? Or is there a specific one needed? Amazon perhaps? Thanks in advance.

I used the ford teflon grease for driveshafts. Works well. I used hose clamps to reattach the boot. Offset the binders/screws 180degrees to avoid any balancing issues.

 

[silver billet]

I used the ford teflon grease for driveshafts. Works well. I used hose clamps to reattach the boot. Offset the binders/screws 180degrees to avoid any balancing issues.

How long as this help up for you so far? Do you reapply every once in a while?

 

[bosco88]

I'm also interested to know how long the teflon grease works for. Don't want to use it if it doesn't last very long.

Follow up question from earlier - what is the torque spec for the drive shaft bolts? I am buying new bolts (not reusing) and wish to ensure I reassemble the drive shaft with the correct torque. I can't seem to find it online. Thanks!

 

[kapinallinen2]