Driveline Clunk. I don't like it. (2 Viewers)

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So I have read a lot of threads where it mentions the clunk noise in the driveline and how it is basically normal.
What I have gathered is that this is just collective lash in the system from age. I know a few of you have had their vehicles since new, was there any clunk initially?

What needs to be replaced to restore the driveline to a "clunk-less" setup?
New gears?
New Driveshafts?
T/M rebuild?
Torque converter?

I might as well buy another rig at the rate I'm buying stuff from Jason at CruiserYard. If there are some small tweaks that can be done, I'd like to do that. I'll have to rebuild the front and rear thirds either way to replace the leaking pinion seals, so if I should be getting new gears and lockers, that seems like the time to do it...
 
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You don't like it? hahaha. I don't think any of us do. Driveshafts are a good place to start. Remove your front driveshaft and see what happens. :cheers:
 
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I appreciate your post, Golgo. I've gone through a litany of things to help bring my LC to baseline but I don't really have a frame of reference. Because of that, I don't know how much further I have to go, if it's irrevocably "ridden hard and put away wet" or what. I also don't know what is normal, what is abnormal and what the amount of refinement should be expected (in general). Wish I did.
 
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You have an A440F (3FE). Try the u-joints, grease the hell out of the zerts and check your front drive shaft flange. You will always have a little clunking going on with the truck this is normal.
 
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Grease the drive shaft splines with moly. If you have a 3fe, you might also loosen up the transmission kick down cable. If it is too tight, the drivelines will clunk and bang.
 
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The cable itself will clunk and bang?
I might be exaggerating a little, but the sound is similar to the sound of a hammer hitting an anvil. Not quite so loud, but you get the idea.
I also want to try to re-route the torque converter lockup control wires and get them plugged in again.

The driveshafts feel tight, but I know the dealer had them off, so I'll double check to make sure they are torqued and tight. The U-Joints are nice and tight as are the splines. However, I will re-grease them and make sure they are lubed. The front shaft is "new" with only about 20k on it. The rear seems to be original.

Thanks guys!

I hope to install a bunch of stuff this weekend and possibly get this beast running again.
I'll have an axle from a '96 in the rear thanks to Jason. The front end is leaking birf soup a bit, but I'm going to check the diff fluid and take it for a drive anyway.
I miss it.
I also have a newer front axle housing on its way which will get installed this winter along with a full rebuild of the axle bearings, seals, etc.
I'll post it to my build thread as it progresses.
 

cruiserdan

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The FJ80 is "clunkier" (if that's a word :lol: ) primarily because of the transfer case. The FZJ80 with the viscous coupler is not as prone since the coupler dampens it. Much of the slop comes from worn drive flanges followed by u-joints and slip yokes. Add a bit for diffs with lots of miles and backlash in the tranfer gears and there you have it.

My wife's 95 has had the coupler removed because it was siezed up and hers clunks much more than mine does because of that. I have a "new" used coupler to put back in it if I ever get around to it.
 
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I believe my chunk is from the trans unlocking. I know when its going to happen just before it happens when I let off the gas under certain conditions.
I will try and pay attention and note those conditions when i drive it next..if I remember.


I do get a chunk/tin like noise from the front diff when shifting forwards to reverse. I rebuilt the front diff (for no reason other than I wanted to replace the bearings at 215,000 miles, thought they would of been worn, they weren't) and the pinion seal leaked after that. The new seal leaked so I had to replace the flange (and seal again). Did it without removing the diff so I assume I didn't get the pinion nut correctly where it needed to be for proper gear adjustment. Been that way for about 200,000 miles so I assume there is not a problem.

I am sure some of my clunk has to do with the front diff slop. I will make a note when I remove the front drive shaft in a month or so and see if the noise changes.
 
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I have owned my 91 since new. The clunking started to develop around 40K miles. She now has 260K miles and I can't really say it's any worse. I have spent a good amount of time and effort over the years to try to reduce the amount of driveline play, but it is the nature of the beast. The differential gears are not the cause, but are added to the equation. The front driveline of the FJ80 has way more play than the rear when you add up all the interfaces. Just pull the driveshafts off the pinion of the front and rear and rotate the companion flanges by hand. The front has about twice the amount of rotational slop than the rear. Again, the nature of the beast.
The hammer/anvil sound is the hollow driveshaft tube. As others have already said, make sure the universal joints are in good shape and well greased and don't forget to grease the slip yolks too. The slip yolks should also be inspected for play and it doesn't hurt to separate the shaft and clean out all the old grease and crap that gets compacted in there. Make sure you have matchmarks on both halves to keep them in proper alignment.

Bottom line, deal with it. It's not going away.
 
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Ima leave myself a note so I can easily link this thread the next time this comes up.

clunk

There.

:lol:
 
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I have owned my 91 since new. The clunking started to develop around 40K miles. She now has 260K miles and I can't really say it's any worse. I have spent a good amount of time and effort over the years to try to reduce the amount of driveline play, but it is the nature of the beast. The differential gears are not the cause, but are added to the equation. The front driveline of the FJ80 has way more play than the rear when you add up all the interfaces. Just pull the driveshafts off the pinion of the front and rear and rotate the companion flanges by hand. The front has about twice the amount of rotational slop than the rear. Again, the nature of the beast.
The hammer/anvil sound is the hollow driveshaft tube. As others have already said, make sure the universal joints are in good shape and well greased and don't forget to grease the slip yolks too. The slip yolks should also be inspected for play and it doesn't hurt to separate the shaft and clean out all the old grease and crap that gets compacted in there. Make sure you have matchmarks on both halves to keep them in proper alignment.

Bottom line, deal with it. It's not going away.
I appreciate you sharing this with us. It's not every day we get to hear about the experiences of the first owner over a period of time. Most of these rigs are on theirs second, third or higher, owners and you don't always get good anecdotal information. Definitely puts things in perspective. Thanks.
 
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Thanks guys. From Jon and Dan's posts it seems like it is as bad as it will get and it isn't necessarily bad so I guess I'll live with it.
The U-Joints on the driveshaft seem OK and the drive flanges themselves don't show any sign of shaft slippage, but I'll be able to see the wear better when I get the everything cleaned before re-greasing.

It is too late to matchmark the driveshaft to the t-case. and the axle is from a different vehicle, so I hope it doesn't become an issue. This truck became a lot of work really fast. I wasn't ready for it and I've been dragging my feet. Good thing I'm taking time off work at Toyota to work on my Toyota...
 
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Most of my clunk was eliminated when I went P/T

That would seem to indicate a large portion of it comes from the front end.
I have a rear third in a bucket in the garage. Maybe this weekend i'll check the resonant frequency(I'll hit it with a hammer) for the sounds to see if it is the same. I can do the same thing with the rear driveshaft to see what sound comes off.

Either way, Dan and Jon put me at ease with the clunk.
 

LandCruiserPhil

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That would seem to indicate a large portion of it comes from the front end.
I have a rear third in a bucket in the garage. Maybe this weekend i'll check the resonant frequency(I'll hit it with a hammer) for the sounds to see if it is the same. I can do the same thing with the rear driveshaft to see what sound comes off.

Either way, Dan and Jon put me at ease with the clunk.


If I had to guess I would say the inter diff of the transfer case is where most of it comes from. You eliminate a lot of gears with a spool.
 
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That would seem to indicate a large portion of it comes from the front end.

Not exactly: Also the slop from both ends traveling through the open center diff.

I'll bet just locking the center eliminates most of it.
 

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