Clunk sound from rear- Anyone ever had a bad half shaft?
- Thread starter supraguy@aol
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Backlash2032;1623802 said:
Same here- I CAN shift without getting the clunk, but but the norm is to get some clunk. SO, All us guys on here that have a clunk, and we can't figure it out...
Poodles;1623198 said:
This is one thing I had go wrong with mine that gave me the clunk I was talking about, they are very strange as as Poodles said are not like normal bushings but more like a pivot joint. They were not fun to replace even with a press. That is what was giving me the clunking sound while taking off and braking.
Mine is driveline related. Reverse to 1st, and vise versa. Occasionally accelerating from stop signs as well.
1986.5supra_kid
Rice? No its Corn (E85)
i started a thread on this as well under 7mge, my supra has the same prob, and im thinking bout just dropping the tranny and getting new clutch and checking out all my u joints. my supra has 130xxx and it maybe the original clutch. my clunk comes when i accelerate and let off acceleratior. acts like the rear end is wore out but done what meta- said and it checks out okay. sounds like clutch or driveshaft for me.
Ive had this clunk on three different chassis now (mint condition with 168K, crappy one with 85K and current cherry at 80K) and 3 different rear ends and 2 different transmission and 2 different driveshafts. I've always figured it to be the diffs as they are not very tight in any supra i've been in, they have a lot of lash in my experience.
Hey bro,
I have the same symptoms you describe here, but I am almost sure mine is the differential. My car has about 171 000 miles on it.
This are the symptoms I have experienced:
- When I engage the clutch from a stop i get a clunk and a sound like two metal plates are slapped against each other.
- When I let off the gas or get back on the gas at low speeds, I feel the clunk from behind quite strongly with the same sound described above.
- When slowing to a red light from a high gear (gear 3 or 4 for example) and then letting off the brakes to coast (car is at about 1000 to 1300 rpm)
the car kinda feels like its hopping from the rear end with the same sound as I am coasting, until I push the clutch in and put it in neutral.
-At very high speeds (in 5th gear) when I let off or get on the gas I feel only a slight tug with no noise.
I spent half a day trying to diagnose this problem one day. I jacked up the car from the rear wheels with the front wheels stopped from rolling. My friend drove the car (at low speeds of course) while I was underneath listening for the noises and it was most definitely resonating from the differential casing.
People have always told me that its normal but I've never felt this on any other rear wheel drive car (open or LSD). After extensive research I believe that clutch type LSDs like the mk3's require a lot of fluid changes to prevent these clunking problems. I'm going to try replacing my differential with a JDM torsen unit and see if I have the same problem.
I have the same symptoms you describe here, but I am almost sure mine is the differential. My car has about 171 000 miles on it.
This are the symptoms I have experienced:
- When I engage the clutch from a stop i get a clunk and a sound like two metal plates are slapped against each other.
- When I let off the gas or get back on the gas at low speeds, I feel the clunk from behind quite strongly with the same sound described above.
- When slowing to a red light from a high gear (gear 3 or 4 for example) and then letting off the brakes to coast (car is at about 1000 to 1300 rpm)
the car kinda feels like its hopping from the rear end with the same sound as I am coasting, until I push the clutch in and put it in neutral.
-At very high speeds (in 5th gear) when I let off or get on the gas I feel only a slight tug with no noise.
I spent half a day trying to diagnose this problem one day. I jacked up the car from the rear wheels with the front wheels stopped from rolling. My friend drove the car (at low speeds of course) while I was underneath listening for the noises and it was most definitely resonating from the differential casing.
People have always told me that its normal but I've never felt this on any other rear wheel drive car (open or LSD). After extensive research I believe that clutch type LSDs like the mk3's require a lot of fluid changes to prevent these clunking problems. I'm going to try replacing my differential with a JDM torsen unit and see if I have the same problem.
I'ts not the LSD...
Toyota (as well as most other OEM's) use a crush sleeve to se the preload on the pinion bearings. Crush sleeves suck, and wear out losing preload on the bearing and allowing the pinion to move around. The only thing at that point keeping the pinion nut on is the staked in part. Put enough force through it (oh, like 4 wheel drive low on 4.11 gears and 31" tires) and it shears the teeth off.
Toyota (as well as most other OEM's) use a crush sleeve to se the preload on the pinion bearings. Crush sleeves suck, and wear out losing preload on the bearing and allowing the pinion to move around. The only thing at that point keeping the pinion nut on is the staked in part. Put enough force through it (oh, like 4 wheel drive low on 4.11 gears and 31" tires) and it shears the teeth off.
Thanks for the insight poodles. Is it costly to overhaul my existing differential and replace this crush sleeve? or do you think I should just swap out the lsd (the whole case) with a cheap lower milage one?
Poodles;1630064 said:
Depends if damage has been done or not. Bearings, or worst case gearset damage would make it expensive.
Replacing the crush sleeve with a fixed spacers with shims is the best way to remedy the issue (and has been done for years on trucks where loads are high).
Replacing the crush sleeve with a fixed spacers with shims is the best way to remedy the issue (and has been done for years on trucks where loads are high).
speedmaster;1630082 said:
Beech performance has solid crush sleeve for like $25
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Has anyone solved this problem. I have it since I own the car 8 years ago. Here are the parts I have changed.
1. Both spherical bushings on outer knuckles.
2. Prop shaft.
3. Center bearing
4. Axles changed to is300 x2 left axles and is300 stubs.
5.gt86 torsen t2 carrier
6. New ring and pinion tight backlash.
7. New poly subframe bushings.
8. New a340e transmission mount.
After all these i still have this same clunk. It happens when shifting from r to n to D and vice versa. Happens when suddenly let off the gas. Also when slowing down to a stop and trans shift to 1st.
Is this why Toyota added diff bushings and guibo for mk4?
1. Both spherical bushings on outer knuckles.
2. Prop shaft.
3. Center bearing
4. Axles changed to is300 x2 left axles and is300 stubs.
5.gt86 torsen t2 carrier
6. New ring and pinion tight backlash.
7. New poly subframe bushings.
8. New a340e transmission mount.
After all these i still have this same clunk. It happens when shifting from r to n to D and vice versa. Happens when suddenly let off the gas. Also when slowing down to a stop and trans shift to 1st.
Is this why Toyota added diff bushings and guibo for mk4?
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I did some searching and will be doing the throttle cable adjustment and drop the pan to see how the cable is interacting.
and also an adjustment on the primary regulator valve, I need to turn mine to the softest setting, I think its now also in the middle.
forum.ih8mud.com
Will report if it helped.
and also an adjustment on the primary regulator valve, I need to turn mine to the softest setting, I think its now also in the middle.
Improving Transmission Shifting
IMHO the auto trans is tuned more on the smooth shift side than I prefer. As lift, weight, larger tires, etc, have been added, it has moved more towards a slip shift end of performance.:frown: So, did a bunch of reading, talked to a trans tech buddy and have tried a few tweaks with good results...
forum.ih8mud.com
Will report if it helped.
I adjusted the primary regulator valve to soft by turning counter clockwise. The valve was stuck at first due to it being in its place untouched for 35 years. A little harder push with a minus screwdriver and it went in. I turned it from center to horzontal like in this pic.
So it helped, but only a by a little. My guess it reduced about 5psi of pressure. The transmisssion shifts nicely as before and does not slip so I will be keeping it in this position. Since I dropped the pan and lost 3.3L, I put back 3.3L of Lubegard Complete ATF.
So in short, it didnt really eliminate the problem but it helped reduce it somewhat.
So it helped, but only a by a little. My guess it reduced about 5psi of pressure. The transmisssion shifts nicely as before and does not slip so I will be keeping it in this position. Since I dropped the pan and lost 3.3L, I put back 3.3L of Lubegard Complete ATF.
So in short, it didnt really eliminate the problem but it helped reduce it somewhat.
OK.. I have thought about it more and next area to look at is the slip Yoke splines of the propeller shaft and output shaft in the gearbox. Has anyone notice wear in the splines. The earliest I can look at it is in 3 weeks time. To clarify further, you dont feel the clunk, but you hear it,
I did go under the rear of the car and get my wife to inch forward and reverse to spot loose movement but I cannot spot anything wrong.
I did go under the rear of the car and get my wife to inch forward and reverse to spot loose movement but I cannot spot anything wrong.
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It seems the clunk sound is coming from the backlash. My ring and pinion is new and my diff LSD carrier is from a GT86 so it is much younger than my original 36 year old open diff innards, so I dont think this slop is coming from the diff internals. It feels like its purely ring and pinion backlash. I measured 0.16mm backlash , but I could have measured it wrong. Is it possible that measuring at a wrong angle could give a much lesser reading of 0.16mm, when the actual is lets say..0.4mm ?
I plan to decrease backlash to about 0.1mm and give it a try...
I plan to decrease backlash to about 0.1mm and give it a try...
Hey Alcyon- Good to see you're still here, but sorry that you're still having this issue. Unfortunately, I'm still having this issue as well, but it's now also evident in my 89 Supra. I've replaced both axles, had Piratetip rebuild a new diff for me, replaced all subframe and rear suspension bushings, new driveshaft, new sphericals, new tranny mount, checked all bolts, and STILL a major clunk on accel/ decel. I'm wondering if maybe the tranny splines are causing the clunk, and the sound is transmitting to the rear? I just don't know. I have to replace my clutch soon, and I may opt to have the R154 rebuilt at the same time.
I had this issue several years ago. Since I didn't want to tear into my rear end right away, I employed the KISS principle right off the bat. I noted that the bag that holds the Supra's heavy jack (located in the hatchback void on the driver's side) was free-floating and would clunk against the sides of the compartment during shifting. I braced the jack with a piece of thick packing foam to prevent its movement. It solved the clunking noise and I haven't heard it since. Of course, YMMV, but if you've replaced every component of your rear end and still have the noise, you might give it a try. Also, take a look at anything floating around in the spare tire well.
Good luck!
Good luck!