Double cardan noise (2 Viewers)

[george_tlc]

Executive summary: Installed a Slee front drive shaft several months ago. The 80 spends most of its time 'resting' but when driving it makes a noise. Vehicle is lifted in the 4" range. 97 CE

Ok, so some history. I changed springs a year or more ago and the growl from running stock driveshafts was obvious. Growl on deaccel. Couple years back had changed all unijoints with new.

Figured the front definitely needed a double cardan, so after the upgraded coils I spent more $ and ordered a Slee double cardan. Install went smooth and had put some grease in, just in case it was shy of some being new. Went for a drive and it seemed 'ok'. Anyhow, from the next drive and as time as gone by and I drive the 80 (once every couple or so weeks) for a short work commute, maybe 3 miles each way and surface roads (35 - 40mph max), it makes a ticking/ringing sound that is correlated with vehicle speed ONLY on acceleration. Lift of the accelerator and it is smooth as can be and quiet as can be, touch the accelerator to put a load on the drivetrain and noise is back. The shaft is not rubbing/tapping against anything.

Today, after a bunch of procrastinating, I dropped the front shaft and locked the center diff and went for a few mile drive. All quiet, no ringing sound, all smooth, all perfect, other than now being a 2wd vehicle

I need to give Christo and gang a call Monday to get their thoughts, but figured I'd see if anyone has had the same issue and/or thoughts of "why is it so".

It is installed with the witness marks on the shaft aligned as it was received from new.

cheers,
george.

 

[Rwhat]

I’m wondering if the springs settled in and now it changed the angles a bit.

 

[george_tlc]

Spring heights are still within 1/4" of 6+ months ago. They are the dual rate dobs and seem very stable height-wise (I also love their ride).

Something is definitely causing the ringing sound. The sound changes with vehicle speed, applying brakes with accelerator applied makes no noise change, so it's definitely the driveshaft, and even more so that removing it removes the sound. The sound started with the new driveshaft.

The sound is like a ding ding ding that changes rate with vehicle speed. Ease off the accelerator (i.e. coast) and sound is gone. I'm not convinced that it's only sound or if even some vibration associated with it. Of course given there's a ding ding sound, there must be some mechanical transfer of energy to create it.

Original driveshaft was smooth on accel and of course growled on deaccel.

cheers,
george.

 

[Rwhat]

Do they use new cardens in the driveshafts?

 

[mudgudgeon]

Sounds like maybe a bad Uni joint. (Yes, even a new one)

Do all the uni joints rotate freely through full range of movement with the DC shaft out?

Have you talked to Slee for their opinion or advice?

 

[george_tlc]

^ Ujoints rotate smoothly through range of motion, all feel tight, no notchy stuff, no play.

Haven't chatted with Christo and gang yet, that's Monday's task (as per my OP).

cheers,
george.

 

[LXDOC]

Where is the front shaft in travel/extension range at ride height?

 

[Kernal]

High percent Moly grease in the center Cardan joint (ball and socket)?

 

[george_tlc]

I'll post some pictures with a tape measure later this evening.

But, quick measurements. Flange face to Flange face of xfer box to front diff is 81cm.

Fully compressed shaft flange to flange face is 78cm.
Extended shaft where you can just begin to see the splines is 88cm

cheers,
george.

 

[george_tlc]

High percent Moly grease in the center Cardan joint (ball and socket)?

It's whatever Slee put in there when they ship. I added a few squirts of paladium moly.

Just playing with the cardan end a few mins ago and there is some notchy action sometimes, it's not clunky or anything, just feels not smooth as you rotate rotate the joint around (without the shaft rotating), basically going through its range of motions. But this requires a reasonable amount of rotation from the through axis.

If I tap the cardan end of the shaft body, it has a similar type ding sound as when it is doing it on the vehicle and slight acceleration/load to the drive train. It's not a windchime ding - but it's certainly in that class of sound/tone.

cheers,
george.

 

[george_tlc]

Some pics.

Flange to flange at parked ride height is 81cm (as above)

With shaft removed, view of the xfer box flange

And ditto for diff flange

Fully compressed shaft

Fully extended shaft with splines just visible

Shaft in fully compressed state and with phasing as shown and delivered from Slee.

cheers,
george.

 

[Augustiron]

Xfr and diff pinions tight w/ no lateral play also?

 

[george_tlc]

Xfr and diff pinions tight w/ no lateral play also?

Yep, both tight and no play in/out or sideways.

cheers,
george.

 

[BILT4ME]

When it was installed, were both ends well seated onto their respective drive flanges? If there was even a tiny gap where the mating flanges were not seated with each other, they will flex with each rotation.
If those flanges to have a new driveshaft installed, there's a lot of debris and gunk.on the faces.
Clean off all flanges, make sure each end seats well and make sure they are torqued properly on all hardware.

And the DC end goes to the transfer case, not the differential.

Is the sway bar dragging on the DS?

 

[mudgudgeon]

IME uni joints have always come with only enough white grease for assembly.

I always pump in moly grease until it spews past every seal and pushes oit no more white grease.
"A couple of squirts" wouldn't do it.

If you're feeling some notchyness, along with the ding sounds, you've got a dud or dry, or broken needle roller in there somewhere

 

[trainbufftony]

Front differential problems like a chipped pinion gear could transfer and ring through a tubular driveline under load then not once the load and amplifying device is removed.
May be a cheap check would be to dump the diff fluid and check for iron contamination if you don't find a problem with the shaft...

 

[Tyland Cruiser]

Some pics.

Flange to flange at parked ride height is 81cm (as above)

With shaft removed, view of the xfer box flange

View attachment 3908515

And ditto for diff flange

View attachment 3908513

Fully compressed shaft

View attachment 3908512

Fully extended shaft with splines just visible

View attachment 3908514

Shaft in fully compressed state and with phasing as shown and delivered from Slee.

View attachment 3908511

cheers,
george.

I had a similar problem with a new drive shaft installed by Slee with the 4" lift they installed on my LC. Slee sourced the drive shaft from J.E. Reel. Slee did not grease the drive shaft when they installed it. When I contacted Slee about it, their response was disappointing. Slee denied any responsibility for not having greased the u-joint when they installed in and instead blamed the manufacturer, but would not contact their own suplier (J.E. Reel). Instead, they insisted that I contact J.E. Reel directly, even though I did not source the drive shaft from J.E. Reel, Slee did. This also meant that I paid to ship the drive shaft back to J.E. Reel, instead of Slee. J.E. Reel sent back my drive shaft with a new u-joint installed, but did not grease it. Normally, a drive shaft should be shipped from the manufacturer already greased. Also, the one-size-fits-all drive shaft that Slee buys from J.E. Reel is too short for a 4" lift. You might want to check yours for proper length. Mine is about an inch too short, which means it could be a problem at full extension.

I ended up buying a Tom Woods drive shaft measured to fit my truck exactly and which is a far superior product and cheaper than what Slee charged for the ungreased, too short J.E. Reel drive shaft they provided. I'll keep the J.E. Reel shaft in my garage as a spare. Couldn't be more disappointed in Slee's failures and refusal to stand behind its work, especially with something so simple as a new drive shaft. There were many other problems with Slee's work on my truck. I won't ever trust my truck with Slee again.

 

[george_tlc]

^ thanks for your post and background. I have reached out to Slee and am waiting to hear back with 'the plan'. Will hold judgement till then

I've dealt with Christo from way back in time when he put together the first sliders for 80's in the days of the lcool forum. Will be interesting to see how things evolve...

cheers,
george.

 

[Tyland Cruiser]

^ thanks for your post and background. I have reached out to Slee and am waiting to hear back with 'the plan'. Will hold judgement till then

I've dealt with Christo from way back in time when he put together the first sliders for 80's in the days of the lcool forum. Will be interesting to see how things evolve...

cheers,
george.

Good luck. I hope you get better results. I left out that Slee's first response was to try to blame me and asked if I had greased the drive shaft after 3k miles, which they claimed was required. I had pointed out the noise when I brought my LC back to Slee at 2k miles for the diff oil change, and they said nothing, nor did they bother to grease the shaft then. Crazy way to treat customers paying top Dollar for what is supposed to be high quality products and workmanship. I have no doubt that Slee legitimately earned its good reputation back in the day. In my experience, they are no longer living up to that reputation.

 

[gonzopancho]

^ thanks for your post and background. I have reached out to Slee and am waiting to hear back with 'the plan'. Will hold judgement till then

I've dealt with Christo from way back in time when he put together the first sliders for 80's in the days of the lcool forum. Will be interesting to see how things evolve...

cheers,
george.

Christo is cool, if a bit standoffish these days. The front off ice guys are hard to deal with. Very aggressive.