The OFFICIAL clunk/thunk driveshaft thread (9 Viewers)

[lexi4darin]

Ok guys, my first time under the car since ownership (3 weeks now) so it was a long day as I had to inspect everything. Things look pretty healthy in general and I'm very impressed. A little seepage from the t-case but at her age I don't think it's major nor unusual. I'll flush and keep my eye on it.

In the meantime, the zerk lubing was a mixed bag of success...

Front propeller is gorgeous. It took grease at the spiders and yokes just fine. The section of the shaft that gets extended when the truck is raised looked like pure metal with little corrosion. I actually degreased/cleaned (careful not to touch any of the seals) and then lubed. However, the rear shaft was another story. It had took grease just fine at the spiders but the slip yoke was reluctant. After some convincing, it did accept grease for a long while but I never got grease to come out the main seal. There's apparently a rear seal that flowed by the spiders, too easily for my liking, and no matter how much grease I injected I never saw the shaft extend from pressure buildup like the front did.

Any thoughts?

 

[NMuzj100]

no matter how much grease I injected I never saw the shaft extend from pressure buildup like the front did.

Any thoughts?

Keep pumping.

 

[lexi4darin]

NMuzj100-

Well, I thought that but here's why I think there may be another problem...

First, I went thru 6 3oz tubes of grease last night for the whole lube project. By the way, I'm using an NLGI #2 Moly-Graph EP (5%) with Lithium for both all the spiders and slip yokes.

Second, the front propeller flowed grease pretty early, taking only 1.5 tubes to do so. Makes the fact that the rear took more than 3 tubes seem extreme.

Lastly, the rear propeller shaft is flowing out the rear of the shaft by the spiders and not out the main seal. Is this normal? Makes me think that there's a problem in the cavity and grease is flowing to the point of least resistance which happens to be backwards away from the main seal.



Another thing, I've already 80 miles since lubing and I'm noticing the situation isn't resolved. I have about a 90% improvement but not a complete 100% fix. Prior to lubing I was getting the clunk 50% of the time when adjusting the height of the FJ100 and it happened on every complete stop/pull away without fail and 100% of the time.

After lubing, the AHC seems to be smoother (quicker too or placebo?) and definitely isn't making any clunk sounds. The clunk sound is completely gone when I stop the car but does still happen when I pull away from a complete stop. About 2 out of every 5 times I pull away from a stop I get the clunk.


What good will it do if I keep lubing and it pours out the rear of the shaft?

 

[cad0411]

I just installed 4 new U joints. Make sure you pump newg rease though the fittings until it comes out all 4 holes before installing. Even thouhg it didn't seem like they were worn out, it still made a huge diffrence. I have just a little play in the drive shaft (splines) which is now barely noticable. I use Toyota OME joints. These are better than anything else. I would highly recommend using Toyota parts.

 

[cad0411]

From what I have learned, too much grease isn't good. Some of it will get settled on one side of the shaft after a long drive. The grease builds up on the inside of the shaft and will cause a unbalanced situation to occur which will cause vibration. It's not hard to fix, but just a little time consuming.

Ok guys, my first time under the car since ownership (3 weeks now) so it was a long day as I had to inspect everything. Things look pretty healthy in general and I'm very impressed. A little seepage from the t-case but at her age I don't think it's major nor unusual. I'll flush and keep my eye on it.

In the meantime, the zerk lubing was a mixed bag of success...

Front propeller is gorgeous. It took grease at the spiders and yokes just fine. The section of the shaft that gets extended when the truck is raised looked like pure metal with little corrosion. I actually degreased/cleaned (careful not to touch any of the seals) and then lubed. However, the rear shaft was another story. It had took grease just fine at the spiders but the slip yoke was reluctant. After some convincing, it did accept grease for a long while but I never got grease to come out the main seal. There's apparently a rear seal that flowed by the spiders, too easily for my liking, and no matter how much grease I injected I never saw the shaft extend from pressure buildup like the front did.

Any thoughts?

 

[scottm]

I'm curious about this famous thunk, has anyone carefully checked their rear suspension mounts? I've replaced bushings that looked good but were worn out. My 100 and 4R so far don't clunk, but I've read plenty about it on forums, and I don't see how the driveshaft alone can cause this. I can see how pressurizing the driveshaft can help, by pushing the rear suspension back, preventing it from shifting.

 

[SupraTuRD]

Mine has a fairly frequent 'clunk' when I shift from reverse to drive. Is this the same "thud" we're talking about here?

I'll shoot some Amsoil grease in the shafts tomorrow to see if it eliminates the noise.

 

[NMuzj100]

Lastly, the rear propeller shaft is flowing out the rear of the shaft by the spiders and not out the main seal. Is this normal? Makes me think that there's a problem in the cavity and grease is flowing to the point of least resistance which happens to be backwards away from the main seal.

What good will it do if I keep lubing and it pours out the rear of the shaft?

There is a seal in the top of the shaft tube and your appears to be leaking allowing/forcing the grease in the wrong direction. This was reported on the board once before. You could try and stick a finger over the point where it leaks and see if you can temporarily contain the grease and force it to purge over the seal. That is how many shafts with relief holes are lubed. Or you will need to remove the shaft and reseat the seal.

Even properly lubed there may be some clunk or thunk. This is a 3 ton vehicle with a lot of driveline parts each with a bit of play. If the clunk is still bad then you need to look to see if there is another cause like worn bushings ect...

From what I have learned, too much grease isn't good. Some of it will get settled on one side of the shaft after a long drive. The grease builds up on the inside of the shaft and will cause a unbalanced situation to occur which will cause vibration. It's not hard to fix, but just a little time consuming.

The Slide Yoke cannot be lubed without filling to capacity purging old emulsified and contaminated grease through the seal. A more likely problem than grease settling is the evaporation/weeping of the oil from the thickener of the grease leaving behind a solidified non-lubricating paste. This will happen with too little grease at too long an interval.

 

[lexi4darin]

NMuzj100

I like where you taking this; some good ideas. I'm going to try your ideas this weekend or next but I want to leave enough time in the day for possibly taking the shaft apart, if necessary. Also, I'm considering the very good chance that I have bad bushings. I know something is loose (suspension wise) on the rear drivers corner. I'll start with bushing in order of importance to me and not likelihood of "clunk" resolution: sway bars, suspension, steering.

I'll keep updating posts but this may be a while until I get to the bottom of it.

 

[ebod]

OK, it's time to lube my drive shaft again. Last time I used NLGI # 2 grease (no moly) that I picked up at pep boys (for both spiders and slide yoke). This time I want to use moly grease for the slide yokes. Pep Boys doesn't have it. My choices at Amazon are:

(1) Sta-Lube SL333 Molygraph Extreme Pressure multi-purpose lithium grease (with Molybdenum and Graphite) NLGI-2; or
(2) Redline CV-2 Grease with Moly (this is synthetic w/ moly). I'm assuming that the "2" in CV-2 means its equivalent to the "2" in NLGI-2.

Which grease should I go with, 1 vs 2 above? Is it a problem if I mix synthetic and regular? Is synthetic that much better for this type of use (daily driver 99% on street)?

Also, what does "not VOC Compliant" mean, from a performance standpoint? Is it a problem if I use not VOC compliant grease?

Thanks in advance!!

 

[NMuzj100]

Also, what does "not VOC Compliant" mean, from a performance standpoint? Is it a problem if I use not VOC compliant grease?

VOC = volatile organic compounds - stuff that causes smog outside or negatively effects air quality indoors when it evaporates.

Has nothing to do with lubricating performance.

This time I want to use moly grease for the slide yokes. Pep Boys doesn't have it.

Either of those two choices might be good but I can't find the details on them I want. I would lean toward Redline at the price.

At Amazon this Valvoline is good:

EP grease with a moly that meets a Ford chassis lube standard requiring moly : Amazon.com: Valvoline 633: Automotive

At Pepboys or other auto store look at these moly-fortified Valvoline greases-
- Valvoline SynPower Synthetic Grease
- Valvoline DuraBlend Synthetic Blend Grease
- Valvoline Moly-Fortified Multi-Purpose Grease Ford

 

[ebod]

Thank you for the suggestion NMuz. I'll look into the Valvoline you suggested (at least at first pass Amazon seemed to have it in a size that doesn't work with my grease gun, but I'll keep searching around). Is there any problem using a grease that has graphite (in addition to Moly)?

 

[lexi4darin]

ebod, I just used your choice #1. Obviously since it's been in the car for just a few days I can't comment much. But it is the choice I made.

dp

 

[NMuzj100]

And this is the stuff I'll be using next ...

Schaeffer Lubricants | Supreme Moly Grease

A little hard to find when buying less than a case. I was nearly eaten by a guard dog at the truck depot I bought mine at. I'll report back when it's field tested.

 

[bkgee]

Being that this is the "official" clunk thread, I'm surprised no one has brought up rear control arm bushings and axle wrap yet. As in this post https://forum.ih8mud.com/100-series-cruisers/91953-100-series-picture-thread-120.html#post5952428

Working out the hundy clunk should be a lot like working out the clunk in the yota mini trucks, a multi technology approach. Eg, for the minis, the clunk can be decreased or eliminated by paying attention to drum brake adjustment, drive shaft lubing, spring replacement, and/or traction bars.

 

[LCHardriver_02]

What is the published (if not published, then typical) life span on the control arm bushings, anyway?

 

[lexi4darin]

I actually brought bushing up in one of my earlier posts. Either in this thread or the one I created a few days ago. I'm planning on rebuilding the rear driveshaft too as I don't think it's accepting grease properly. I'll post follow ups as that work progresses.

It would be nice if someone could list the bushing in the rear of the vehicle so I can put together a game plan. Originally, I stated ] that I will approach bushings starting with what's more important to me instead of likely to fix the issue: sways, suspension, then steering. I may change my approach to target the clunk.


Am I right for thinking 70-100k is the normal life expectancy of OEM bushings (poly's not included)? No idea if that holds true but when I did my GS430 at 75k it made a noticeable difference. The LX has 135k on it with the original OEM bushings. They're brittle toast.

 

[ebod]

So, anyone have any thoughts as to whether grease with graphite will be bad for the slide yokes (the grease has moly too)?

Note this grease will not go in the spiders.

 

[scottm]

The problem with moly is that it's too slippery for the rolling elements of a roller bearing - they might not roll without enough friction. So graphite, moly, and other friction reducers are only an issue with roller bearings.

 

[NMuzj100]

Being that this is the "official" clunk thread, I'm surprised no one has brought up rear control arm bushings and axle wrap yet. As in this post https://forum.ih8mud.com/100-series-cruisers/91953-100-series-picture-thread-120.html#post5952428

Working out the hundy clunk should be a lot like working out the clunk in the yota mini trucks, a multi technology approach. Eg, for the minis, the clunk can be decreased or eliminated by paying attention to drum brake adjustment, drive shaft lubing, spring replacement, and/or traction bars.

This thread is about the "driveshaft clunk/thunk" which is a fairly simple and very common problem. It is not about every problem that makes a noise.

If generous lubing of the slide yokes with a good grease doesn't substantially improve the problem then you have a different issue.