what does a failing u-joint sound like?
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so i broke my DS trans yoke at the track a while back, i ordered a new yoke from PST and i just installed it yesterday.
i took the car for a test drive, and i'm getting a rhythmic clunking sound from the drivetrain. ka-klunk... ka-klunk... happens at all speeds, and increases in frequency accordingly. i lifted the rear wheels off the ground and ran the car like that in both fwd and reverse... you can still hear it, but its a lot quieter, you gotta be listening for it. clearly louder when driving on the street.
i have a moser 12 bolt /w tru-trac, and i only put down like 350 to the wheels, so i doubt i f'd up my rear when the DS yoke broke.
i wonder if the yoke they sent me is too long
i coulda swore that when i installed this DS the first time, i could slide the trans yoke in quite a bit so i could manuever the back end into the rear end yoke. this time, i pushed the trans yoke in as far as it would go, and i still had to use a screwdriver to pry the rear DS u-joint onto the rear end yoke.... maybe it was just cuz i had jackstands on the rear end when i was doing the install (instead of the frame), so there was just less room
. but if the DS Trans yoke was too long, and that was causing a weird inbalance, wouldnt the clunking be the same if the rear was jacked up or if i was running on the street?
i took the car for a test drive, and i'm getting a rhythmic clunking sound from the drivetrain. ka-klunk... ka-klunk... happens at all speeds, and increases in frequency accordingly. i lifted the rear wheels off the ground and ran the car like that in both fwd and reverse... you can still hear it, but its a lot quieter, you gotta be listening for it. clearly louder when driving on the street.
i have a moser 12 bolt /w tru-trac, and i only put down like 350 to the wheels, so i doubt i f'd up my rear when the DS yoke broke.
i wonder if the yoke they sent me is too long
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the clunk would be the yoke bottoming out on the output shaft. and it would be louder on the street b/c there is always suspension travel going on while it is bottoming out. a failing u joint makes a chirping type noise. i would take that yoke out and measure it to see if it is the same length as a stock one.
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yeah i dunno what the deal is here but if i broke a driveshaft i wouldn't have installed a new one without new U joints also, but thats just me. I say compare old to new to see if there is any differences and go from there.
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ok, i just pulled out the DS. i compared it to a 3rd gen DS (which i'm pretty sure is the same length as an LS1 DS), and they were both approx 46.75-47" from the center of the rear u-joint cap to the tip of the trans yoke.
i then got under the car, and measured from the end of the trans housing to the rear end yoke (which is the center of where the u-joint cap sits), and that was approx 44.0". i did this measurement with the front tires on the ground, and the rear end on jackstands.
so that would mean the DS is sticking into the transmission 2.75-3" (plus the length of the output shaft that sticks out of the trans). i looked at the tip of the DS trans yoke, and it does not appear to be dinged up
if i measure the two parts separate, i see that the aftermarket DS is .5" shorter, but the yoke is .5" longer:
PST DS - 41"
PST Yoke - 6"
3rd gen DS - 41.5"
3rd gen yoke - 5.5"
i have a moser 12-bolt... this thread here seems to support my measurements, and also that the 12-bolt takes the same length as stock https://ls1tech.com/forums/gears-axl...riveshaft.html
i then got under the car, and measured from the end of the trans housing to the rear end yoke (which is the center of where the u-joint cap sits), and that was approx 44.0". i did this measurement with the front tires on the ground, and the rear end on jackstands.
so that would mean the DS is sticking into the transmission 2.75-3" (plus the length of the output shaft that sticks out of the trans). i looked at the tip of the DS trans yoke, and it does not appear to be dinged up
if i measure the two parts separate, i see that the aftermarket DS is .5" shorter, but the yoke is .5" longer:
PST DS - 41"
PST Yoke - 6"
3rd gen DS - 41.5"
3rd gen yoke - 5.5"
i have a moser 12-bolt... this thread here seems to support my measurements, and also that the 12-bolt takes the same length as stock https://ls1tech.com/forums/gears-axl...riveshaft.html
Last edited by slayer_taunu; 07-25-2009 at 02:16 PM.
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you mean install it 180 degrees? i would, but i didnt mark it before i pulled it out... 50/50 chance on that ![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
in my OP, i stated that the DS was hard to install because it felt like i dindt have much room to move it in and out and had to pry it over the rear yoke. when i just installed it, it came out very easy, like normal. must have just been the way the suspension was loaded, not giving me enough play room.
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in my OP, i stated that the DS was hard to install because it felt like i dindt have much room to move it in and out and had to pry it over the rear yoke. when i just installed it, it came out very easy, like normal. must have just been the way the suspension was loaded, not giving me enough play room.
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it shouldnt be too long... its the same length as stock.
would taking the driveshaft to a driveshaft shop and put on the balancing machine reveal if the u-joints are clunking or not? or does it not put enough load on it to reveal stuff like that?
would taking the driveshaft to a driveshaft shop and put on the balancing machine reveal if the u-joints are clunking or not? or does it not put enough load on it to reveal stuff like that?
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ok, i went to driveshaft king. really nice guys to work with there. the guy drops everything to look at my driveshaft. he tugs on all the ujoints, the yoke, pops he caps off to inspect them... he throws it on a lathe to watch it spin... says there's nothing wrong with it and doesnt suggest that i even waste my time getting it balanced.
so that leaves me with the rear end... f'ing great.
so that leaves me with the rear end... f'ing great.
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popped the cover off... guess what i found ![Sad](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_sad.gif)
anyone know how much it costs to get new gears installed (parts & labor)?
and is it safe to drive the car with broken teeth just to go 40 or so miles to the shop to get new gears installed?
![](http://i60.photobucket.com/albums/h34/slayer_taunu/car%20repairs%20and%20installs/broken%20driveshaft%202/IMG_1288.jpg)
![](http://i60.photobucket.com/albums/h34/slayer_taunu/car%20repairs%20and%20installs/broken%20driveshaft%202/IMG_1303.jpg)
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anyone know how much it costs to get new gears installed (parts & labor)?
and is it safe to drive the car with broken teeth just to go 40 or so miles to the shop to get new gears installed?
![](http://i60.photobucket.com/albums/h34/slayer_taunu/car%20repairs%20and%20installs/broken%20driveshaft%202/IMG_1288.jpg)
![](http://i60.photobucket.com/albums/h34/slayer_taunu/car%20repairs%20and%20installs/broken%20driveshaft%202/IMG_1303.jpg)
![](http://i60.photobucket.com/albums/h34/slayer_taunu/car%20repairs%20and%20installs/broken%20driveshaft%202/IMG_1292.jpg)
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yeah, i just had the same thing happen to my car but I built the rearend myself. It is really easy to take out if you want me to go step by step with you and I could get you pictures as well because I just took mine out last night, takes about two to three hours to take it out and put it back in if you are mechanically inclined.
if you decide not to do it yourself, just make sure you have the mechanic use the correct gear oil (it should say it in your driver's manual, I don't know off the top of my head) and also go to like advance auto parts and they have this stuff in a little white and black tooth paste looking thing -- i believe its called "trans x" and its gear oil additive so it won't slip definetly worth the 7-8 dollars though
if you decide not to do it yourself, just make sure you have the mechanic use the correct gear oil (it should say it in your driver's manual, I don't know off the top of my head) and also go to like advance auto parts and they have this stuff in a little white and black tooth paste looking thing -- i believe its called "trans x" and its gear oil additive so it won't slip definetly worth the 7-8 dollars though
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oh one more thing, the hardest part is getting the pinion out that sits on the other side of your driveshaft (from the transmission), its a 36mm nut and you will need another person to hold the yoke or whatever you want to call it (the thing that holds your u-joint/driveshaft) with a pair of decently sized channel locks to get that thing out, again its not that bad. Since I'm fairly bored and trying to kill time I'll go ahead and break down what you have to do and get you some pictures tomorrow evening, I know most of this stuff off the top of my head.
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read the last thing I wrote before doing this --
Jack up the back of the car, make sure it is fairly secure and make sure it is as high as you can get it on Jack Stands. Put a peice of wood infront of the front tire.
-Removing the rearend + gearing.
Put the car in Neutral.
Spin Driveshaft so you can see the two 11mm bolts holding the driveshaft to the yoke of the rearend, then put the car in park.
Remove two 11mm bolts that hold the U-Joint in place, do the samething to the other side.
*DO NOT REMOVE YOUR DRIVESHAFT, push the driveshaft in to the transmission 2-3 inches and use a pry bar or something similuar to hold the driveshaft in place (I used a pry bar and put it over the exhuast piping and the other thing hanging and it worked perfectly you have to push it up though a few inches). The reason for this is if you leak transmission fluid and do not fill it up properly it will a) **** up the transmission and b) it also makes a huge mess.
Once done, remove both rear wheels.
Remove rear brake callipurs from brackets and find a way to secure them (use a small but high enough box, do not leave tension on the brake lines!).
Take the Rear Rotors off.
Remove yoke out of rear end, friend holding channel locks around the very tip of the yoke very tightly, use a 36mm 1/2 drive ratchet + extension and start using those muscles.
Now, looking where you took off your pumpkin looking in to the differential -- on both sides of the differential carrier case (the weird looking thing in the middle) remove the 4 alan key looking bolts that are on both ends. After this is done, have a friend put one of the rotors back on and push the rear axle this will push it further in to the differential carrier ( make sure you spin the rotor so you can see the inside of the carrier, there is a small hole or box on one side and a bigger one on the other), after this is done take a long flat head screw driver and remove the C-CLIP at the end of the axle. Do not lose that C-Clip, they are a bitch to find. After this is done, to the same thing on the other side and remove the axles.
Now, the differential carrier case should just come right out (the thing your broken ring gear is attached to). Another thing, there will be two bearings and races (one on each side of the carrier) the bearings are pressed on the carrier case, the races are loose and there will also be two spacers that go outside of the races (one on each side) DO NOT LOSE OR BREAK THESE PARTS!! If you have to Shim your differential it will be a pain in the *** and you will never get it right (I mean you will but its a lot more headaches and a lot more trial and error. You will have to angle it a little bit so it can get past the rear sway bar. Now, get a rag and wipe the hell out of your differential (you want to get ALL the medal chunks out).
Once out, remove the gear from the carrier. Remember, these bolts are posi so you will have to turn the ratchet clock-wise to loosen these bolts. They should be 17mm, when installing you will turn the ratchet counter clock-wise to tighten the new ring gear on to the differential carrier case.
Now all thats left is the pinion, where you took the nut off that was a 36mm, get a socket that you DO NOT NEED as well as a long 3/8ths extension and put it on the end of the pinion (thats what the 36mm nut went around) and tap it with a hammer. Doing this will prevent you from damaging the threads and it should just pop out, it will take some hitting because a bearing is pressed on to it toward the back of the gear. One more thing, there is a little black spacer maybe an inch long and its a pretty wide little thing, DO NOT LOSE THIS AND MAKE SURE TO PUT IT BACK ON WHEN REINSTALLING. Remove pinion gear, inspect for damage and clean all the differential (yes, including the back -- metal chunks will be there as well.
Install is reverse of taking it out. As far as setting the back-lash and things like that, I know how to do it but I'm not sure how I would explain how to do it. Google it or if anyone could tell you on here.
Honestly though, if you like cars and stuff its definetly worth it and if you like working on cars, go for it. It's pretty cool, fairly simple... Looks like a lot but its really not. Just make sure you get a fan or something so you don't die from heat exhaustion. Good luck.
One more thing, if you have automatic a4 v8 make sure you get 3.23's -- i put 4:10s in mine and was topping out at about 70-80 mph at like 5 rpms ... not worth it and I wouldn't do 3.73s either. Another bad thing is it will throw off your speedo as well. I went back to 3.23s. While you are at it, I'd try to sell your differential carrier case on these forums or something and spend about 700 +/- on an EATON limited Slip Differential Carrier and some Richmond Gearing on like jegs or something. Just be sure to get the series 3 carrier and the series 3, 323 gearing. Will make the car a lot more fun. If not, just use stock differential carrier and go to advance 180/190 dollars to get motive gear, 3.23 gearing -- they will have to special order it -- will take a day or two. Remember, you will need a bearing and race pressed on the pinion before reinstalling it, I would inspect and reuse if the one on the old pinion looks good, if not I would not reuse. I would also replace the wheel bearings out while you have the rear axles out of the car. They are about 5-6 dollars for each and 3 dollars for automotive grease because the first time I did the differential on my car, a few weeks later the wheel bearings went out and its ashame to do the same ******* job twice. Hahah, good luck again.
Jack up the back of the car, make sure it is fairly secure and make sure it is as high as you can get it on Jack Stands. Put a peice of wood infront of the front tire.
-Removing the rearend + gearing.
Put the car in Neutral.
Spin Driveshaft so you can see the two 11mm bolts holding the driveshaft to the yoke of the rearend, then put the car in park.
Remove two 11mm bolts that hold the U-Joint in place, do the samething to the other side.
*DO NOT REMOVE YOUR DRIVESHAFT, push the driveshaft in to the transmission 2-3 inches and use a pry bar or something similuar to hold the driveshaft in place (I used a pry bar and put it over the exhuast piping and the other thing hanging and it worked perfectly you have to push it up though a few inches). The reason for this is if you leak transmission fluid and do not fill it up properly it will a) **** up the transmission and b) it also makes a huge mess.
Once done, remove both rear wheels.
Remove rear brake callipurs from brackets and find a way to secure them (use a small but high enough box, do not leave tension on the brake lines!).
Take the Rear Rotors off.
Remove yoke out of rear end, friend holding channel locks around the very tip of the yoke very tightly, use a 36mm 1/2 drive ratchet + extension and start using those muscles.
Now, looking where you took off your pumpkin looking in to the differential -- on both sides of the differential carrier case (the weird looking thing in the middle) remove the 4 alan key looking bolts that are on both ends. After this is done, have a friend put one of the rotors back on and push the rear axle this will push it further in to the differential carrier ( make sure you spin the rotor so you can see the inside of the carrier, there is a small hole or box on one side and a bigger one on the other), after this is done take a long flat head screw driver and remove the C-CLIP at the end of the axle. Do not lose that C-Clip, they are a bitch to find. After this is done, to the same thing on the other side and remove the axles.
Now, the differential carrier case should just come right out (the thing your broken ring gear is attached to). Another thing, there will be two bearings and races (one on each side of the carrier) the bearings are pressed on the carrier case, the races are loose and there will also be two spacers that go outside of the races (one on each side) DO NOT LOSE OR BREAK THESE PARTS!! If you have to Shim your differential it will be a pain in the *** and you will never get it right (I mean you will but its a lot more headaches and a lot more trial and error. You will have to angle it a little bit so it can get past the rear sway bar. Now, get a rag and wipe the hell out of your differential (you want to get ALL the medal chunks out).
Once out, remove the gear from the carrier. Remember, these bolts are posi so you will have to turn the ratchet clock-wise to loosen these bolts. They should be 17mm, when installing you will turn the ratchet counter clock-wise to tighten the new ring gear on to the differential carrier case.
Now all thats left is the pinion, where you took the nut off that was a 36mm, get a socket that you DO NOT NEED as well as a long 3/8ths extension and put it on the end of the pinion (thats what the 36mm nut went around) and tap it with a hammer. Doing this will prevent you from damaging the threads and it should just pop out, it will take some hitting because a bearing is pressed on to it toward the back of the gear. One more thing, there is a little black spacer maybe an inch long and its a pretty wide little thing, DO NOT LOSE THIS AND MAKE SURE TO PUT IT BACK ON WHEN REINSTALLING. Remove pinion gear, inspect for damage and clean all the differential (yes, including the back -- metal chunks will be there as well.
Install is reverse of taking it out. As far as setting the back-lash and things like that, I know how to do it but I'm not sure how I would explain how to do it. Google it or if anyone could tell you on here.
Honestly though, if you like cars and stuff its definetly worth it and if you like working on cars, go for it. It's pretty cool, fairly simple... Looks like a lot but its really not. Just make sure you get a fan or something so you don't die from heat exhaustion. Good luck.
One more thing, if you have automatic a4 v8 make sure you get 3.23's -- i put 4:10s in mine and was topping out at about 70-80 mph at like 5 rpms ... not worth it and I wouldn't do 3.73s either. Another bad thing is it will throw off your speedo as well. I went back to 3.23s. While you are at it, I'd try to sell your differential carrier case on these forums or something and spend about 700 +/- on an EATON limited Slip Differential Carrier and some Richmond Gearing on like jegs or something. Just be sure to get the series 3 carrier and the series 3, 323 gearing. Will make the car a lot more fun. If not, just use stock differential carrier and go to advance 180/190 dollars to get motive gear, 3.23 gearing -- they will have to special order it -- will take a day or two. Remember, you will need a bearing and race pressed on the pinion before reinstalling it, I would inspect and reuse if the one on the old pinion looks good, if not I would not reuse. I would also replace the wheel bearings out while you have the rear axles out of the car. They are about 5-6 dollars for each and 3 dollars for automotive grease because the first time I did the differential on my car, a few weeks later the wheel bearings went out and its ashame to do the same ******* job twice. Hahah, good luck again.
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******* AWESOME! This is the exact sound I am hearing with my car. I'm kinda of nervous about taking it anywhere but because I don't know really want to tell them it sounds like, but now that I see this...damn I think I might have something to go on. Thanks for the post.
Let me know how much it cost to get it fixed.
Pork
Let me know how much it cost to get it fixed.
Pork
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got it all fixed last night.
price will vary by the installer obviously, but my guy originally told me $450-500 depending on part cost. but also keep in mind that i have a moser 12-bolt, not a factory 10-bolt, so there might be a part/labor difference there too. my installer said that generally 12-bolts take a little longer to do.
price will vary by the installer obviously, but my guy originally told me $450-500 depending on part cost. but also keep in mind that i have a moser 12-bolt, not a factory 10-bolt, so there might be a part/labor difference there too. my installer said that generally 12-bolts take a little longer to do.
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there shouldn't be any difference in price for labor and it shouldn't take any longer to time wise to do it over a 10 bolt. They are the same style rearend but just have 2 extra bolts. Most shops in my area get about $250 labor. That's what I would charge if I did it and you supplied all the parts.
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How can you tell backlash from a picture???
To think, all this time I been using a dial indicator to check backlash, and I never really needed it. All I needed was just to look at it the gears.
.
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