The OFFICIAL clunk/thunk driveshaft thread (1 Viewer)

[2000UZJ]

I got a new one for you guys... this one only happens when the car has come to a complete stop.

Pull up to a stop, wait a few seconds and then get a squelchy klunk in the front left hand corner that i can feel through the break pedal....

Make sure those calipers are torqued down properly. Check CV play also.

 

[Wellcraft19]

Thought I'd add my $10 of grease to this thread as well.

I did lube my universal joints and the slider yokes on the drive shafts yesterday evening.

The universal joints, no issues. The drive shaft to the rear axle took many, many pumps. One could finally start to see the slider to move a bit, and eventually grease to start leaking out. Knew it was under pressure, even though it likely also slowly "settled" over time, I waited a while and then did remove the zerk fitting to relieve pressure, and sure enough, a fair amount of grease squirted back out and a small "chank" (from the frame) when that pressure was relieved (expected).

Front slider yoke was better, grease started leaking out much sooner.

BUT, this really did nothing for the "thunk" in the drive line. With engine off, car in Park, handbrake pulled etc (me under the car), one can still "twist" both front and rear drive axle a little bit. There is noticeable play in the transfer case, and both front and rear differentials, so I guess my little "thunk" stems from there. Not the "external" drive line components.

Anyone else seen this?

 

[Layonnn]

I'm guessing this is similar to the FJC but you are definitely not supposed to over grease the slip yoke on the drive shaft, the drive shaft extends and compresses. If it's full of grease, it has no room to compress. Anyone ever heard this about the 100 DS? This is part of the reason it's taking some people 30+ pumps to start seeing grease come out.

 

[OregonLC]

Mine took about a week for the grease to work into the parts. Now 75% of the time I can't even hear the engagement from D to R.

I never did get grease to purge from the slip yoke. And I pumped something like 30+ stokes with my Lincoln into it. Got the hydraulic action (driveline moved forward). I figure it's probably just hard grease up in the splines. I'll keep injecting once a month or so until it works free.

I also took a surprising number of pumps on the 4 u-joints before grease came out. I continued to pump until the red Amsoil was the only thing coming out. You can wind a heavy shop towel into a rope and floss around all sides to clean the excess.

 

[blkcruiser]

clunk

I've found that instead of going from reverse to drive, I go into N for a second then hit drive and there isn't usually a clunk that way.

 

[tnlandcruiser]

I found the same thing after reading this thread. I thought there was no way I was still moving, parking on the tranny, etc. After reading this thread I did 2 things. 1. Anytime I shifted from D to R or vice versa, I stop in neutral, release and reapply the brake, then move on. 2. When parking. I put it in neutral, set the ebrake, then shift to D. My D/R thump is drastically less noticeable. In addition, since using Moly on the slides the driveline think is also gone. Of course right now I'm tracking other possible tranny issues entirely, but this thread cured both my clunk and my D/R issues.

 

[OregonLC]

When parking. I put it in neutral, set the ebrake, then shift to D.

I'm assuming you mean P and not D, but that's the way you should park any vehicle. Set the e-brake, trans in N, foot off brake, trans in P. That puts zero load on the trans unless the vehicle creeps in which case you need to adjust your e-brake.

That said, this method will cure the 'pop' that can be felt with the parking pawl releases and the tension in the drivetrain is unloaded but it won't necessarily cure the D-R thunk. Grease is the cure for the common thunk.

 

[2000UZJ]

I'm assuming you mean P and not D, but that's the way you should park any vehicle. Set the e-brake, trans in N, foot off brake, trans in P. That puts zero load on the trans unless the vehicle creeps in which case you need to adjust your e-brake.

That said, this method will cure the 'pop' that can be felt with the parking pawl releases and the tension in the drivetrain is unloaded but it won't necessarily cure the D-R thunk. Grease is the cure for the common thunk.

When I was at URE few months ago we all parked on this hill, I was afraid I was going to blow the trans apart if I just put it in park, the e-brake could not hold worth a damn. I found a tree and nosed in on it. Worked great!

 

[Wellcraft19]

Going back to my post above (#162). Suspected the little "thunk" was from the "lack of grease" (as widely debate here on MUD in many threads), but in my case it is play (not necessarily excessive) in the transfer case and the diffs. Hard to say how many degrees, but when grabbing the axle, you can twist it back and forth a little bit.

@Layonnn: Agree with the not "over grease" the slip joint. That's why I also released the extra pressure created by pumping to actually get to see grease come out past the seal.

 

[NMuzj100]

I'm guessing this is similar to the FJC but you are definitely not supposed to over grease the slip yoke on the drive shaft, the drive shaft extends and compresses. If it's full of grease, it has no room to compress. Anyone ever heard this about the 100 DS? This is part of the reason it's taking some people 30+ pumps to start seeing grease come out.

Don't spread misinformation. You are definitely supposed to grease the slip joints (Yoke) on the drive shaft until it purges old grease past the seal.

It's in the FSM, in all driveshaft service manuals and proven by the experience of the board. The manual recommends daily greasing if engaged in river crossings. The drive shafts cannot be "over greased".

The reason people are having to pump so much grease is under-serviced yokes with obstructed seals. The constant action of the slip joint consumes the oils in the grease over time. The rear shaft does have capacity for quite a bit of grease because it is a big unit.

 

[NMuzj100]

drive shaft to the rear axle took many, many pumps. One could finally start to see the slider to move a bit, and eventually grease to start leaking out. Knew it was under pressure,

With regular service the grease may eventually emulsify/dissolve the grime blocking your drive shaft seals so they flow smoothly. If not then you may need to disassemble the shaft and clean the seal.

BUT, this really did nothing for the "thunk" in the drive line. ..., one can still "twist" both front and rear drive axle a little bit. There is noticeable play in the transfer case, and both front and rear differentials, so I guess my little "thunk" stems from there. Not the "external" drive line components.

Anyone else seen this?

Did you use a molt-fortified grease?

Are you sure the play is not in the u-joints ? When twisting do the flange yokes leading into the diffs and transfer move. Substantial play in the transfer or differentials has not been widely reported on the board so yours would be somewhat rare.

If you start really slow does the "thunk" happen prior to or simultaneously with initial motion or later at a little bit of speed? The driveshaft "thunk" caused by the slip joint tends to happen a little after start when forces demanding the joint to slide suddenly overcome the friction between the under-lubricated splines.

There are other problems that will result in noises from the drive train but i think you were smart to try lubing the driveshaft first.

 

[OregonLC]

but in my case it is play (not necessarily excessive) in the transfer case and the diffs. Hard to say how many degrees, but when grabbing the axle, you can twist it back and forth a little bit.

Every driveline ever made has this. Lots of moving parts and when you add up the tolerances between interfaces there's some degree of slop.

@Layonnn: Agree with the not "over grease" the slip joint. That's why I also released the extra pressure created by pumping to actually get to see grease come out past the seal.

How would releasing pressure get grease to come out past the seal. More pressure is required, not less right?

 

[Wellcraft19]

Did you use a molt-fortified grease?

Are you sure the play is not in the u-joints ? When twisting do the flange yokes leading into the diffs and transfer move. Substantial play in the transfer or differentials has not been widely reported on the board so yours would be somewhat rare.

If you start really slow does the "thunk" happen prior to or simultaneously with initial motion or later at a little bit of speed? The driveshaft "thunk" caused by the slip joint tends to happen a little after start when forces demanding the joint to slide suddenly overcome the friction between the under-lubricated splines.

There are other problems that will result in noises from the drive train but i think you were smart to try lubing the driveshaft first.

NMuzj100, thanks for piping in. I think you are the real forum master on this issue (as on many others, greatly appreciate your input and sharing of info):

Yes, used Moly fortified grease, NGLS #2 (from CRC, had at home, Amsoil for next fill of gun).

There is no play in the U-joints, it is in the tranny/diffs. And the (although muted) "thunk" is when engaging "D" (or "R" for that matter). Nothing while driving and shifting gear.

Every driveline ever made has this. Lots of moving parts and when you add up the tolerances between interfaces there's some degree of slop.

How would releasing pressure get grease to come out past the seal. More pressure is required, not less right?

I agree on the "some degree" of slop. Just had not seen it mentioned much around here.

And I had a fair amount of grease pass by the seal on the slip yoke, but it was also was under pressure, so before starting driving, I released it by removing the Zerk, and then added a bit more (a few pumps), only until I saw the slip youke actually move again.

 

[Layonnn]

So ALL toyota driveshaft slip joints should be greased til grease comes out?

I greased my rear shaft and ujoint and the front ujoint at the transfer case. I couldn't get to the front ones cause of the stock skid but will get to it this weekend when i do the oil. But, just from what i have greased so far, i have noticed a significant amount of reduction in the "clunk".

 

[re_guderian]

gauntlet thrown down, pin on the grenade pulled... 5, 4, 3, ...

Are we gonna rehash the 80-series arguments again? Can we please have some physics involved if we do?

 

[RobRed]

Why has this shifted to a transmission thunk thread? I thought this was a driveline thread?

 

[Wellcraft19]

Why has this shifted to a transmission thunk thread? I thought this was a driveline thread?

Because of me. Trying to get rid of the muted "thunk" in the "drive line". Greasing the slip yokes, and the u-joints resulted in no noticeable effect.

So while while under, saw that I could twist drive shaft a bit (and it seems like when twisting the front shaft, the rear one moves (through the center diff) the exact same amount.

Part from that, no issues.

 

[NMuzj100]

gauntlet thrown down, pin on the grenade pulled... 5, 4, 3, ...

Are we gonna rehash the 80-series arguments again? Can we please have some physics involved if we do?

We are way past the 80 series arguments and now dealing with FJ arguments.

Do try and keep up.

 

[re_guderian]

We are way past the 80 series arguments and now dealing with FJ arguments.

Do try and keep up.

my bad... Could we still talk physics though??

 

[lexi4darin]

"Turn and burn Mav"