CV Joint bolts...
#1
Burning Brakes
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CV Joint bolts...
hey, in my driveline rebiuld adventure i replaced the CV joints. Everything is cool, except that tonight when i was driving home, i heard a knocking and pinging noise coming from the rear, i found that my CV joint bolts on one side were coming loose! and knocking againts parts. I think i remember torquing them, but i guess not accurately. Does anybody have the correct torque spec, and is it a good idea to put some Loc Tight on the bolts also?
#2
Drifting
Some people safety wire them. I just check mine every so often. I found it helps to torque them while the wheels are on the ground. THEY WILL BACK OUT AND CAUSE THE AXEL TO FALL OFF! Ask me how I know.
Crawl under there and tighten em up a bit and you should be OK. Just check them every now and then (oil changes are a good time to go over it).
Crawl under there and tighten em up a bit and you should be OK. Just check them every now and then (oil changes are a good time to go over it).
#3
Race Car
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Damn -- that's scary. It must be the rotational motion that causes it. Good thing you noticed!
According to Haynes - driveaxle bolt, 30 ft-lbs which isn't a whole lot...
Does anybody have the correct torque spec
#4
Rennlist Member
in relation to this problem, since it sounds you already got your answer im going to steal the thread.. i took out the bolts that hold the rear axle halfshaft to the transmission. how do i pull the shft off the transmission? all i can seem to get off is the dust cap which shows bearings or such.
thanks
thanks
#5
Three Wheelin'
Yep 30 ft-lbs has been recommended on here and is what I torqued mine to yesterday in replacing my axles.
The axle with CVs on it should literally fall off of the transmission once you get it unbolted. There is only a very small lip that it sits in where the bolts secure it to the tranny. The bolts only have threads on about 1/3 of the end so they don't have to be taken all the way out, but pull them out so that the heads hit the rubber boot and that should be plenty. Be careful on the passenger side as in your car there is probably nothing keeping it from falling all the way to the ground. On my turbo the tranny cooler line gets in its way.
With the two socket wrenches I had, I would not have torqued them enough laying under a low car on jackstands if I hadn't bought that little torque wrench. I just got the $20 0-75 one at Sears with the 3/8" drive. that worked very well and 30 is almost in the center of the range, so that should be where this wrench is at least fairly accurate. I gave mine a bit over 30 just to be on the safe side though. Was fine and still tight after about 30 miles of driving on 3 occasions (2 very short and one to town to pick up some Chinese!) and the car go to warm up completely then and I was able to boost a few times.
Good luck!
The axle with CVs on it should literally fall off of the transmission once you get it unbolted. There is only a very small lip that it sits in where the bolts secure it to the tranny. The bolts only have threads on about 1/3 of the end so they don't have to be taken all the way out, but pull them out so that the heads hit the rubber boot and that should be plenty. Be careful on the passenger side as in your car there is probably nothing keeping it from falling all the way to the ground. On my turbo the tranny cooler line gets in its way.
With the two socket wrenches I had, I would not have torqued them enough laying under a low car on jackstands if I hadn't bought that little torque wrench. I just got the $20 0-75 one at Sears with the 3/8" drive. that worked very well and 30 is almost in the center of the range, so that should be where this wrench is at least fairly accurate. I gave mine a bit over 30 just to be on the safe side though. Was fine and still tight after about 30 miles of driving on 3 occasions (2 very short and one to town to pick up some Chinese!) and the car go to warm up completely then and I was able to boost a few times.
Good luck!
#6
Three Wheelin'
Oh, I saw this yesterday....might help.
http://www.clarks-garage.com/shop-manual/susp-11.htm
Note...on the left side of the CV axle in this drawing you see a spline piece sticking out from the CV axle. It does NOT come out with the axle...don't expect it to. Just FYI
Enjoy!
http://www.clarks-garage.com/shop-manual/susp-11.htm
Note...on the left side of the CV axle in this drawing you see a spline piece sticking out from the CV axle. It does NOT come out with the axle...don't expect it to. Just FYI
Enjoy!
#7
Rennlist Member
well it doesnt seem to just fall off. i took the bolts out (2 of which were loose and looked like they could have broken, but it looks like it wouldve been al the way past where the shaft is held on.. i dont know what to do now, the shaft doesn't move. are bearings goign to come flying out under the dust cap when i pull it?
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#9
Use blue loctite in the bolts and have them drilled and safety wired.
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#10
Three Wheelin'
I'll chime in here cause i've played with these bolts a few times. Some will also tell you that you should not re-use the bolts you take out, i believe these bolts are in some way stretched upon torquing. Someone else can verify this for me...
What i usually do, and i haven't had any problems yet, is to torque them to whatever it says 30ft-lbs, then i go drive the car for a little bit. Once i get back i recheck the torque spec on each bolt.
Also as an aside - I did break the head off one of these bolts one time, and i absolutely needed to drive the car from Philly to MA. So i did, kept it under 70mph with a wrench in the passengers seat. I checked them at rest stops and not one had loosened up. Luckily i got my hands on some spares the next day.
Good Luck!
Erich
What i usually do, and i haven't had any problems yet, is to torque them to whatever it says 30ft-lbs, then i go drive the car for a little bit. Once i get back i recheck the torque spec on each bolt.
Also as an aside - I did break the head off one of these bolts one time, and i absolutely needed to drive the car from Philly to MA. So i did, kept it under 70mph with a wrench in the passengers seat. I checked them at rest stops and not one had loosened up. Luckily i got my hands on some spares the next day.
Good Luck!
Erich
#11
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Originally posted by ErichCS
I'll chime in here cause i've played with these bolts a few times. Some will also tell you that you should not re-use the bolts you take out, i believe these bolts are in some way stretched upon torquing. Someone else can verify this for me...
I'll chime in here cause i've played with these bolts a few times. Some will also tell you that you should not re-use the bolts you take out, i believe these bolts are in some way stretched upon torquing. Someone else can verify this for me...
#12
Three Wheelin'
You really shouldn't need to mess with the dustcap at all, most of that entire metal piece will come off that the dustcap is over. It's only there to allow the axle to move in the CV up and down and keep the grease in there so it doesn't escape.
Try removing all of the bolts on both sides (at the wheel as well if you are taking this off to rebuild/regrease or replace) of that CV axle and that should give it the movement range it needs to come off. If nothing else, totally remove all of the bolts from both sides and the use a block of wood against the axle and peck on it with a hammer in case it's stuck a bit. It may be that it just doesn't have enough freedom to come loose with the bolts still in at the wheel side or that over time the grease dried out and those two pieces of metal have kind of been glued together by dried out grease.
Mine were removed last year by a mechanic who installed my 87 suspension parts, so mine weren't that long in place being on there after the last removal this time.
My axles came with all brand new ones, but I kept the old ones just in case I lost one.
I actually ruined a Lisle triple-square tool in the process of the first one. The bolt heads are perfect but the bit is all twisted at the end....too dang hard to hold it in there, but better that than the bolt head getting messed up!
Try removing all of the bolts on both sides (at the wheel as well if you are taking this off to rebuild/regrease or replace) of that CV axle and that should give it the movement range it needs to come off. If nothing else, totally remove all of the bolts from both sides and the use a block of wood against the axle and peck on it with a hammer in case it's stuck a bit. It may be that it just doesn't have enough freedom to come loose with the bolts still in at the wheel side or that over time the grease dried out and those two pieces of metal have kind of been glued together by dried out grease.
Mine were removed last year by a mechanic who installed my 87 suspension parts, so mine weren't that long in place being on there after the last removal this time.
My axles came with all brand new ones, but I kept the old ones just in case I lost one.
I actually ruined a Lisle triple-square tool in the process of the first one. The bolt heads are perfect but the bit is all twisted at the end....too dang hard to hold it in there, but better that than the bolt head getting messed up!
#14
Race Director
"i believe these bolts are in some way stretched upon torquing. Someone else can verify this for me..."
Yes, the bolts stretch when you tighten them. That's to generate tension to provide clamping force to hold the CV to the flange. It's this clamping force that generates the friction that holds the parts together and transmits power. If the bolts are loose, they'be be loaded in shear and will get snapped pretty easily. But the bolts aren't stretched to the yield point of the metal, if they were, there would be no clamping force at all; the metal will no longer be elastic, but enters a plastic phase when stressed beyond their yield point.
Some tips for re-installing the bolts:
- clean off both mating surfaces fully, no grease, no oil, clean with acetone to remove traces
- clean off the threads in the flanges as best you can with acetone on Q-tips
- clean out the holes in the CV-joints, bigger Q-tips may be needed
- clean off the threads on the bolts and use blue Loctite
- insert bolts and tighten in several passes in criss-cross pattern like lug-nuts
- use a torque-wrench, 30-lb•ft will feel like you're gonna snap them, but that's correct
I've found it's even more secure to get slightly longer bolts and use a lock-washer. Also drilling them for safety wire wouldn't be a bad idea either. If the bolts come loose and break on the A-arm side, you'll be fine because they're captured. But if they come off on the tranny side, you're in trouble. The flailing axle will take out your exhaust on the left side and take out your gas-tank and pump on the right.
Yes, the bolts stretch when you tighten them. That's to generate tension to provide clamping force to hold the CV to the flange. It's this clamping force that generates the friction that holds the parts together and transmits power. If the bolts are loose, they'be be loaded in shear and will get snapped pretty easily. But the bolts aren't stretched to the yield point of the metal, if they were, there would be no clamping force at all; the metal will no longer be elastic, but enters a plastic phase when stressed beyond their yield point.
Some tips for re-installing the bolts:
- clean off both mating surfaces fully, no grease, no oil, clean with acetone to remove traces
- clean off the threads in the flanges as best you can with acetone on Q-tips
- clean out the holes in the CV-joints, bigger Q-tips may be needed
- clean off the threads on the bolts and use blue Loctite
- insert bolts and tighten in several passes in criss-cross pattern like lug-nuts
- use a torque-wrench, 30-lb•ft will feel like you're gonna snap them, but that's correct
I've found it's even more secure to get slightly longer bolts and use a lock-washer. Also drilling them for safety wire wouldn't be a bad idea either. If the bolts come loose and break on the A-arm side, you'll be fine because they're captured. But if they come off on the tranny side, you're in trouble. The flailing axle will take out your exhaust on the left side and take out your gas-tank and pump on the right.