Just pump grease in, until first extend of slip yoke noted.
Vehicle should be on ground, in neutral stance. Which puts slip yokes, in neutral position.
The OFFICIAL clunk/thunk driveshaft thread
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Vehicle should be on ground, in neutral stance. Which puts slip yokes, in neutral position.
TEQAdventure
SILVER Star
I replaced the front driveshaft and it reduced the clunk a good bit. Still have it but it’s better. I swear mine is because I have too mush backlash at the diff. I can roll my vehicle several inches when in park. I am not sure how to fix that though.
I had a ton of backlash as well, esp at the rear diff. Did not measure but I'd say at least 10* of +/- rotation at the flange with no movement at the tires with the rear in the air. I went forward with my project anyway b/c I already had the DS in hand. There must be a pretty tolerant/open drive-line lash spec, because the new DS's eliminated the clunking (among other things).
I'm debating whether I want to pursue the clunk as far as the driveshafts. I've done:
- hub flanges
- CVs
- greased drive shafts
- front diff bushings
I feel like it's gotta be diff gearing backlash, driveshafts, or maybe motor mounts? I've spent a lot of money so far so I'm kind of close to the eff it stage haha.
- hub flanges
- CVs
- greased drive shafts
- front diff bushings
I feel like it's gotta be diff gearing backlash, driveshafts, or maybe motor mounts? I've spent a lot of money so far so I'm kind of close to the eff it stage haha.
How bad is it? Do the slip joints on your drive shaft take grease / do you see movement in the driveshaft when greasing it up / does it pass grease around the seal?
I feel your pain the clunk is really annoying. CV and hub flanges sorted me out, after I threw a bunch of other parts at it, like replacing front diff bushing that definetly weren't even bad in the first place....but this thread tells a long sad story of how many parts people throw at the clunk trying to fix it and nothing ever works.
I say send it, its not hurting anything...Try to go easy on the gas pedal when coasting ...roll a bit between P-R-N-D shift to try and soften that clunk as well...otherwise you may be destined to keep chasing problems / fixing parts
TEQAdventure
SILVER Star
I don’t have the R to D clunk at all, just driveline from coast to accel. It is really freaking annoying. It seems loudest most violent from front driveshaft, but they both do it. To validate I pulled the front driveshaft and used the CDL and it was gone. With the new driveshaft it is back but somewhat muted. I do notice it is worse around corners, so maybe a motor or trans mount compounding it. When the front driveshaft was out totally it was clear that was the main culprit. I am just not sure how to address since I now have a brand new OEM driveshaft. I have two 100 series (98 and 03), had the 98 for 7 years and it has never done this. The 2003 I bought has done it for years according to previous owner. Only difference I can tell is the amount of backlash in the axles.
I haven’t gone through all 36 pages of this thread but I’d throw out there the front differential bushings. I had some clunks when shifting into drive, I would also hear it when coasting and then applying throttle. Replaced two of three and it has gone away. Just my two. Clunks will make you lose sleep. Good luck.
To be fair, some of us threw every part imaginable at it and it did work. I haven't had clunk in years now.
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The endless thread. I've been chasing my thunk for quite a while. For reference my LX has 217,000 miles, I'm the original owner, and most everything is OEM. I've been living with the thunk for quite some time. It didn't bother me all that much until I began to obsess over it and refused to give up until I solved the riddle. Along the way I replaced my front differential bushings, upper rear differential control arms, and rear drive shaft entirely. When I replaced the driveshaft I used Stay-Lube moly-graphite grease for the splines and Stay-Lube Red for the u-joints. At that point the thunk was reduced but not gone. My thunk was related to releasing the brakes after a stop. With the new front differential bushings the thunk was less pronounced but still present. After some reading I learned that Stay-Lube moly-graphite grease is only about 0.5% moly. AI said that that's not enough moly. I finally decided to drop the front of the rear driveshaft and clean out the Stay-Lube and replace it with Loctite LB 8012 Moly Paste which is 65% moly! Thunk GONE. I used to use Honda 60% moly on my motorcycle splines but sadly they changed the formulation and now it's no longer recommended for use with splines. Like the Loctite LB 8012. Unfortunately this Loctite formulation isn't amenable to using a grease gun. And, it's not cheap. For now, I just loaded up the splines with it. The paste is too thick to go in though a Zerk fitting. So, to "inject" this paste you must either separate the joint and apply the lube or remove the Zerk and inject the paste using a syringe without a needle. I haven't done this yet but it seems doable. When injecting I will push the paste into the joint until I see it seep past the seal. I'll then exercise the suspension to expel excess grease as needed to allow normal spline movement and finally replace the Zerk to seal it up. Thoughts?
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215k on my 05 LX currently, and 100% as you describe. Yes I've read the entire thread at least 3 times.
I greased my original driveshaft splines using regular red grease because I didn't know any better. The clunk improved a bit but slowly came back. Old worn out u-joints and horrible aftermarket replacements pushed me into replacing the driveshaft with OEM. I had also read that the new driveshafts had a new coating on the spines (maybe Teflon) to reduce stiction. That said, the thunk would go away and stay away. I'd bet money that the high moly content pastes will solve the issue for the long term. Why Lexus/Toyota don't recommend it? Probably because they can't just use their grease guns to lube them. I'm going to try using a 60ml Luer Lock syringe using a blunt injection needle through the Zerk threaded hole. A whole pack of various sizes of blunt needles is about $6 on Amz.
BamaOverland
SILVER Star
ok, I hear you here... I have always VERY CAUTIOUSLY greased the slip joint... Is this my problem? the internet seems split and i've read that OVER GREASING can damaged the drive train. have i been wrong? I have the thunk and ive replaced everything (bushings, flanges, etc, etc).
Not 100% but I thought I remember someone on T4R saying screw it and just pumped a bunch in and it got better. Never tried myself, slight brake clunk currently. CV+flanges got rid of all the P-D-P play I used to have.
I'm an "overgreaser" (pump until grease comes past the seal) and have never had any trouble.
The first time I did it, the grease reservoir must have been dry; it took almost an entire tube of grease to do both shafts.
I too don't want to over grease as it might cause a hydro-lock condition that can be very destructive. #1 priority is to get 60-65% moly on those splines. #2 is to put some reserve moly in the void with the spines. Just using the brush in the can of Loctite paste I was able to generously slather both the male and female splines to a very satisfactory level. I'm still debating injecting more in the void but, for now, have decided to just drive and be listening/feeling for any indication of the need for more lubrication. I don't mind experimenting on my stuff to learn what's best. If and when I inject paste through the Zerk hole I'll be cautious and leave the Zerk off while I drive the car for maybe 10's of miles and exercise the AHC suspension from high to low and back, to ensure that the splines aren't liquid locked, before putting the Zerk back in place. If I can go 30K miles without any thunk/clunk then I'll just simply drop the front U-joints, of each drive shaft, and pull the splines apart to relubricate then while I lube the front wheel bearings on schedule.
I agree with pumping until the seal oozes. Anything less and you just don't know. I spend 20 years maintaining spines on motorcycle shafts. Those that didn't use 60% moly often found out that the case-hardening of the splines would fail and they'd open the drive shaft and see nothing but brown, iron, dust and failed splines. Those that always used the Honda 60% moly didn't have issues unless there were other contributing factors such as a plugged oil passage into that same area.
Hey! Can you explain this more? It ended up fixing your D to R clunk? You adjusted the kick down cable near the throttle body in engine bay?
Can you post more on the exact blunt needle you will use for the 60ml Luer Lock syringe if i can manage to get my hands on the 60% moly in Canada for the slip yokes? Greasing the slip yoke (up to 5% moly) and the u joints with their grease has never reduced my R to D etc clunk nor has new oem cvs and hub flanges. Did three days ago again and clunk still there. I want to try your method and see before i possibly take them all off and get done by hand opening them up. Haven't bought new drive shafts rear and front yet. Put in new U-joints 30k miles ago on original shafts.
I don't have any stop and go clunk on my 99 LX470 with 302,000 miles. I do hear clunk from original sway bar end links on back, pry tested all rear suspension and they are clicking/ clunking. Have all toyota parts for those and rear upper and lower control arms and even pan hard bar on my shelf. Brand new for past year. Current ones are all original but when i and my mechanic pal did the pry bar tests and looked at bushings in rear parts, they all looked still in good shape (302,000 miles a lot highway driven) except for sway bar links with play in them and their bushings look bad.
I read someone else fixed their shifting clunk on 99 LX by adjusting their acceleration kick down cable. Interesting. My last commenton here is a question to that person.
@WanderingWarrior, your last comment made me go really deep into a rabbit hole looking for that 60% moly grease, thanks for that!
I believe that this thread is so complicated that made everyone paranoid about clunky stuff in our cruisers.
There’s MANY places where clunks can come from on this car, from drive half shafts (CVs) to bushings and driveshafts from transfer case to axles.
If we’re talking about the shafts going from the axle housing to the wheels (CV axles), then we know that there might be play in splines and repair is replacement of axle/ flange. I did it and it worked!
If bushings, then there’s a solution as well by replacing 1 or all bushings in the whole suspension and axle holding system, how deep you want to go?
I replaced all 3 front axle support points bushings, and feels like butter being squeezed on warm bread.
If inside the axle house (gears) then you know what it means, a pretty expensive job that most people don’t know how to tackle, but doable if you want your LC to keep chugging.
If we’re talking about the drive shafts (“s” as 2 of them in our rigs) usually displayed as a slight bump 1/2 a second after you reach a full stop, or a bump between the moment you release your brake pedal and reach the accelerator pedal, then we’re dealing with the slip joints in those shafts, which are splined as well, need grease to operate properly, and the type of grease needed can spark an endless debate.
(See Ford’s forums for examples).
I managed to, mostly, keep it quiet by injecting grease in there every oil change.
Took me a few tries to get old grease through the seal, but eventually it did come out and now I know it’s flowing. I use whatever grease is in the gun that day.
I cleaned the seal slide area (the shinier part that the seal moves through) with emery cloth several times until old grease came out, never used too much pressure, just enough to make it flow.
I pump a few times every oil change, some grease comes out, I’m good to move on.
I used Moly grease, same as red lithium, and yellow stuff, no matter, same results, the “clunk” lets me know that I’m due for an oil change.
Edited to add that I drove a 2021 LC back in 2021, and it Also Clunked between gears! So it isn’t a problem, it’s just how a multi-linked 4x4 system on a very heavy truck works, it has so many points of contact between your gear lever to the wheels that it’s pretty much impossible to soften them all, specially when said vehicle is 25yo!
So @WanderingWarrior , I’m not following that rabbit today! Even though it’s an interesting chemical that I might get just to play with it a bit and form yet Another theory.
Maybe I’ll use it in an F150 to blow their minds in their really confusing forums!
I believe that this thread is so complicated that made everyone paranoid about clunky stuff in our cruisers.
There’s MANY places where clunks can come from on this car, from drive half shafts (CVs) to bushings and driveshafts from transfer case to axles.
If we’re talking about the shafts going from the axle housing to the wheels (CV axles), then we know that there might be play in splines and repair is replacement of axle/ flange. I did it and it worked!
If bushings, then there’s a solution as well by replacing 1 or all bushings in the whole suspension and axle holding system, how deep you want to go?
I replaced all 3 front axle support points bushings, and feels like butter being squeezed on warm bread.
If inside the axle house (gears) then you know what it means, a pretty expensive job that most people don’t know how to tackle, but doable if you want your LC to keep chugging.
If we’re talking about the drive shafts (“s” as 2 of them in our rigs) usually displayed as a slight bump 1/2 a second after you reach a full stop, or a bump between the moment you release your brake pedal and reach the accelerator pedal, then we’re dealing with the slip joints in those shafts, which are splined as well, need grease to operate properly, and the type of grease needed can spark an endless debate.
(See Ford’s forums for examples).
I managed to, mostly, keep it quiet by injecting grease in there every oil change.
Took me a few tries to get old grease through the seal, but eventually it did come out and now I know it’s flowing. I use whatever grease is in the gun that day.
I cleaned the seal slide area (the shinier part that the seal moves through) with emery cloth several times until old grease came out, never used too much pressure, just enough to make it flow.
I pump a few times every oil change, some grease comes out, I’m good to move on.
I used Moly grease, same as red lithium, and yellow stuff, no matter, same results, the “clunk” lets me know that I’m due for an oil change.
Edited to add that I drove a 2021 LC back in 2021, and it Also Clunked between gears! So it isn’t a problem, it’s just how a multi-linked 4x4 system on a very heavy truck works, it has so many points of contact between your gear lever to the wheels that it’s pretty much impossible to soften them all, specially when said vehicle is 25yo!
So @WanderingWarrior , I’m not following that rabbit today! Even though it’s an interesting chemical that I might get just to play with it a bit and form yet Another theory.
Maybe I’ll use it in an F150 to blow their minds in their really confusing forums!
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I used to get a mild-to-moderate clunk every 3000-4000 miles after greasing the slip yokes.
Then I replaced motor mounts, trans mount, diff mount, front halfshafts, hub splines, wheel bearings, etc.
Now the "clunk" that I get that reminds me to grease the slip yokes is close to unnoticeable.
Then I replaced motor mounts, trans mount, diff mount, front halfshafts, hub splines, wheel bearings, etc.
Now the "clunk" that I get that reminds me to grease the slip yokes is close to unnoticeable.