What happens if CV joints snap?

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Zenmervolt

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Oct 22, 2000
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Originally posted by: jemcam
With a front wheel drive car? I've never experienced it, I'll be honest, but one of the reasons front wheel drive works is because the transaxle equally distributes the power to both wheels. If it's uneven at all, you get torque steer.
Actually, no. Torque steer is a function of the torque creating a gyroscopic effect on the wheels because of the location of the steering pivot axis. It doesn't care about torque distribution too much.

An open differential on a FWD car will still send 100% of the power to the slipping wheel.

ZV
 

jemcam

Diamond Member
Jan 3, 2001
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Originally posted by: iamwiz82
Originally posted by: jemcam
know that on solid axle vehicles, the caliper will hold the axle in place, also

Care to explain that one to me? The caliper is bolted usually with two bolts to a cast iron bracket, which in turn is attached to the axle in the rear. The axle is held in place by 2 trailing arms attached to the frame or unibody rail. In the front, they're held in place by being attached to a bracket and attached to the strut.

Can you give an example? If if the caliper holds the axle in place, what allows the rear axle up and down movement?

Think about it. If I do a brake job on a solid axle car, the rear axle is hanging free when I unbolt the calipers? I don't think so.

You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.

Can you explain why a caliper would NOT hold a broken shaft in?

No, the axles are held in place in the differential, not by the calipers. How do you explain the majority of rear wheel drive cars that have drum brakes? No caliper, what's holding the axle on? If you remove all the brake hardware, you can't pull the axle out.

 

Zenmervolt

Elite member
Oct 22, 2000
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Originally posted by: jemcam
Originally posted by: Zenmervolt
Originally posted by: Scootin159
yeah, that's the halfshaft. Alright, you're right then :). The transaxle is basically the transmission, but it's called a transaxle when it straddles the axle (as in most FWD cars).
Actually, it's only called a transaxle when the differential is integrated into the transmission housing. If the differential is a separate unit, then the car has a transmission.

ZV
Trivia question:

What domestic muscle car in the 1960's had a rear transaxle, yet was a front engine car? (hint: it was a GM)
Pontiac Tempest Slant 4.

ZV
 

iamwiz82

Lifer
Jan 10, 2001
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Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
know that on solid axle vehicles, the caliper will hold the axle in place, also

Care to explain that one to me? The caliper is bolted usually with two bolts to a cast iron bracket, which in turn is attached to the axle in the rear. The axle is held in place by 2 trailing arms attached to the frame or unibody rail. In the front, they're held in place by being attached to a bracket and attached to the strut.

Can you give an example? If if the caliper holds the axle in place, what allows the rear axle up and down movement?

Think about it. If I do a brake job on a solid axle car, the rear axle is hanging free when I unbolt the calipers? I don't think so.

You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.

Can you explain why a caliper would NOT hold a broken shaft in?

No, the axles are held in place in the differential, not by the calipers. How do you explain the majority of rear wheel drive cars that have drum brakes? No caliper, what's holding the axle on? If you remove all the brake hardware, you can't pull the axle out.

A majority of solid axles today are c clip axles.
 

jemcam

Diamond Member
Jan 3, 2001
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Originally posted by: Zenmervolt
Originally posted by: jemcam
With a front wheel drive car? I've never experienced it, I'll be honest, but one of the reasons front wheel drive works is because the transaxle equally distributes the power to both wheels. If it's uneven at all, you get torque steer.
Actually, no. Torque steer is a function of the torque creating a gyroscopic effect on the wheels because of the location of the steering pivot axis. It doesn't care about torque distribution too much.

An open differential on a FWD car will still send 100% of the power to the slipping wheel.

ZV

a gyroscopic effect on the wheels

Where do you learn this crap? You're telling me that if more power is sent to one whell than the other, you won't experience torque steer?

Link to torque steer definition.
 

iamwiz82

Lifer
Jan 10, 2001
30,772
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Originally posted by: jemcam
Originally posted by: Zenmervolt
Originally posted by: jemcam
With a front wheel drive car? I've never experienced it, I'll be honest, but one of the reasons front wheel drive works is because the transaxle equally distributes the power to both wheels. If it's uneven at all, you get torque steer.
Actually, no. Torque steer is a function of the torque creating a gyroscopic effect on the wheels because of the location of the steering pivot axis. It doesn't care about torque distribution too much.

An open differential on a FWD car will still send 100% of the power to the slipping wheel.

ZV

a gyroscopic effect on the wheels

Where do you learn this crap?

a normal transaxle works like a opendifferential, only one wheel gets power. Hence the reason that FWDs can be modified with LSD. If they did(transaxles) always powered each wheel equally, if would be equivilent of a locked diff.
 

jemcam

Diamond Member
Jan 3, 2001
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Originally posted by: iamwiz82
Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
know that on solid axle vehicles, the caliper will hold the axle in place, also

Care to explain that one to me? The caliper is bolted usually with two bolts to a cast iron bracket, which in turn is attached to the axle in the rear. The axle is held in place by 2 trailing arms attached to the frame or unibody rail. In the front, they're held in place by being attached to a bracket and attached to the strut.

Can you give an example? If if the caliper holds the axle in place, what allows the rear axle up and down movement?

Think about it. If I do a brake job on a solid axle car, the rear axle is hanging free when I unbolt the calipers? I don't think so.

You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.

Can you explain why a caliper would NOT hold a broken shaft in?

No, the axles are held in place in the differential, not by the calipers. How do you explain the majority of rear wheel drive cars that have drum brakes? No caliper, what's holding the axle on? If you remove all the brake hardware, you can't pull the axle out.

A majority of solid axles today are c clip axles.


TY!
 

Thegonagle

Diamond Member
Jun 8, 2000
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Originally posted by: jemcam

With a front wheel drive car? I've never experienced it, I'll be honest, but one of the reasons front wheel drive works is because the transaxle equally distributes the power to both wheels. If it's uneven at all, you get torque steer.

Power is distrubuted evenly only if both sides have equal traction.

Whether the differential is in the front, or the rear, it works the same; If one wheel can't put any power to the ground, it will spin while the other does nothing. If one half-axle is disconnected from the wheel due to a failed CV joint, that axle will spin and the other wheel will do nothing.
 

jemcam

Diamond Member
Jan 3, 2001
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Originally posted by: iamwiz82
Originally posted by: jemcam
Originally posted by: Zenmervolt
Originally posted by: jemcam
With a front wheel drive car? I've never experienced it, I'll be honest, but one of the reasons front wheel drive works is because the transaxle equally distributes the power to both wheels. If it's uneven at all, you get torque steer.
Actually, no. Torque steer is a function of the torque creating a gyroscopic effect on the wheels because of the location of the steering pivot axis. It doesn't care about torque distribution too much.

An open differential on a FWD car will still send 100% of the power to the slipping wheel.

ZV

a gyroscopic effect on the wheels

Where do you learn this crap?

a normal transaxle works like a opendifferential, only one wheel gets power. Hence the reason that FWDs can be modified with LSD. If they did(transaxles) always powered each wheel equally, if would be equivilent of a locked diff.

Okay, you've got a point, if it were a locked diff, the tires would wear out in no time when turning. The wheels turn at a different rate when going through a corner.

I stand corrected on this one!

 

iamwiz82

Lifer
Jan 10, 2001
30,772
13
81
Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
know that on solid axle vehicles, the caliper will hold the axle in place, also

Care to explain that one to me? The caliper is bolted usually with two bolts to a cast iron bracket, which in turn is attached to the axle in the rear. The axle is held in place by 2 trailing arms attached to the frame or unibody rail. In the front, they're held in place by being attached to a bracket and attached to the strut.

Can you give an example? If if the caliper holds the axle in place, what allows the rear axle up and down movement?

Think about it. If I do a brake job on a solid axle car, the rear axle is hanging free when I unbolt the calipers? I don't think so.

You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.

Can you explain why a caliper would NOT hold a broken shaft in?

No, the axles are held in place in the differential, not by the calipers. How do you explain the majority of rear wheel drive cars that have drum brakes? No caliper, what's holding the axle on? If you remove all the brake hardware, you can't pull the axle out.

A majority of solid axles today are c clip axles.


TY!

i'm not following you. I said that the brake hardware(caliper) would hold the axle in if it broke in half. I have seen it happen on the trail. I have seen trucks drive out on broken axles without it falling completely out.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Originally posted by: jemcam
Where do you learn this crap? You're telling me that if more power is sent to one whell than the other, you won't experience torque steer?

Link to torque steer definition.
Torque steer is a result of suspension design, not of differential setup. Note that equal length halfshafts (the simplest way to improve torque steer) have nothing to do with whether or not the differential is open or not. Torque steer is NOT a lateral pull on the car, torque steer is the spontaneous change of STEERING ANGLE. Severe torque steer can (and sometimes will) rip the steering wheel out of your hands. The effect on the steering is NOT the by-product, it's the main effect. Wheelspin does not cause the pull on the steering, the torque to the steered wheels (and the resultant gyroscopic effects due to the steering pivot axis not being aligned with the center of the contact patch) causes the pull on the steered wheels. If the front wheels were to pivot about the center of the tire's contact patch, there would not be torque steer.

ZV
 

jemcam

Diamond Member
Jan 3, 2001
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Originally posted by: iamwiz82
Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
Originally posted by: iamwiz82
Originally posted by: jemcam
know that on solid axle vehicles, the caliper will hold the axle in place, also

Care to explain that one to me? The caliper is bolted usually with two bolts to a cast iron bracket, which in turn is attached to the axle in the rear. The axle is held in place by 2 trailing arms attached to the frame or unibody rail. In the front, they're held in place by being attached to a bracket and attached to the strut.

Can you give an example? If if the caliper holds the axle in place, what allows the rear axle up and down movement?

Think about it. If I do a brake job on a solid axle car, the rear axle is hanging free when I unbolt the calipers? I don't think so.

You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.

Can you explain why a caliper would NOT hold a broken shaft in?

No, the axles are held in place in the differential, not by the calipers. How do you explain the majority of rear wheel drive cars that have drum brakes? No caliper, what's holding the axle on? If you remove all the brake hardware, you can't pull the axle out.

A majority of solid axles today are c clip axles.


TY!

i'm not following you. I said that the brake hardware(caliper) would hold the axle in if it broke in half. I have seen it happen on the trail. I have seen trucks drive out on broken axles without it falling completely out.

Nevermind, we were talking about two different subjects. I thought you were talking about the rear axle housing, hence my comment about trailing arms. It didn't make sense to me. My point was first, that the axle HOUSING was not held in place by the calipers (duh) and the brake hardware also is not the primary hardware that holds the axle shaft in place. I've seen plenty of wrecked cars that have had the axle shaft snapped off at the ends of the housing and you have to disassemble the differential to get that broken axle out if you're lucky. You can't just drill a hole on them and take a slide hammer to get them out, you've got to remove the c clips.

 

jemcam

Diamond Member
Jan 3, 2001
3,676
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Originally posted by: Zenmervolt
Originally posted by: jemcam
Where do you learn this crap? You're telling me that if more power is sent to one whell than the other, you won't experience torque steer?

Link to torque steer definition.
Torque steer is a result of suspension design, not of differential setup. Note that equal length halfshafts (the simplest way to improve torque steer) have nothing to do with whether or not the differential is open or not. Torque steer is NOT a lateral pull on the car, torque steer is the spontaneous change of STEERING ANGLE. Severe torque steer can (and sometimes will) rip the steering wheel out of your hands. The effect on the steering is NOT the by-product, it's the main effect. Wheelspin does not cause the pull on the steering, the torque to the steered wheels (and the resultant gyroscopic effects due to the steering pivot axis not being aligned with the center of the contact patch) causes the pull on the steered wheels. If the front wheels were to pivot about the center of the tire's contact patch, there would not be torque steer.

ZV


Look up two posts.
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
44
91
Originally posted by: jemcam
Originally posted by: Zenmervolt
Originally posted by: jemcam
Where do you learn this crap? You're telling me that if more power is sent to one whell than the other, you won't experience torque steer?

Link to torque steer definition.
Torque steer is a result of suspension design, not of differential setup. Note that equal length halfshafts (the simplest way to improve torque steer) have nothing to do with whether or not the differential is open or not. Torque steer is NOT a lateral pull on the car, torque steer is the spontaneous change of STEERING ANGLE. Severe torque steer can (and sometimes will) rip the steering wheel out of your hands. The effect on the steering is NOT the by-product, it's the main effect. Wheelspin does not cause the pull on the steering, the torque to the steered wheels (and the resultant gyroscopic effects due to the steering pivot axis not being aligned with the center of the contact patch) causes the pull on the steered wheels. If the front wheels were to pivot about the center of the tire's contact patch, there would not be torque steer.

ZV
Look up two posts.
Yeah, that wasn't there when I started with my reply. I'm a slow typist. :eek: BTW, was I right on the trivia question with my answer of Pontiac Tempest with the Slant 4?

ZV
 

Ly2n

Senior member
Dec 26, 2001
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If a CV joint breaks power is lost. The car won't move. I know because it happened to me on a trip. The inner CV joint disconnected from the transaxle. All of the power went to the disconnected side, and we couldn't move. A tow truck, about 6 bolts and we were on our way.
 

Evadman

Administrator Emeritus<br>Elite Member
Feb 18, 2001
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Originally posted by: Scootin159
Generally if a CV joint goes the worst problem would be a LOUD clicking sound from the axle, especially on turns. If it were to SNAP (which it really can't do, but I guess it COULD fall apart) it would just leave the wheel freewheeling.
I snapped the outer joint on my tercel. Grenaded is more like it. I decided to try a neutral drop from redline while showing off. Whoops. It was about $100 for another half shaft. Generaly, when a joint starts to go, you will hear a clicking when turning. At that point, it is time to get a new one, and send your old one back as core while it is still rebuildable. You can get a split boot to repair it, but they are a PITA to do. Just get a reman one.
Originally posted by: Garfang
If the CV joint by the wheel does go, that end of the driveshaft could fall out and do damage, depending on the type of inner CV joint used (tripod vs. ball bearing). Most use a tripod style inner joint that allows the shaft to move in and out.
That is true. the innner joint takes up the in and out, and up and down play, while the outer does the turning and the rest of the up and down. because of the turning, outers tend to go first. As for the shaft coming out, it can, but only if the half shaft breaks. if you just grenade the outer one (like I did) then it will stay in the car, contained by the hub system, and usually the outer race (unless you REALLY toasted that joint)
Originally posted by: Garfang
Actually, the car will not go at all, unless there is a limited slip differential (almost no FWD cars have one). Of course, if it did have a LSD, and you tried to drive it, the LSD wouldn't work for long because you would burn it out quick!
Actually, in either case the car will not go at all. in an open diff, the wheel with the least amount of traction will get the power. A LSD (limited slip differential) transmits to both. but most requre a force of some kind to be on both sides. the LSD has to ramp up, and to do that, some force from both wheels is required. If the joint goes, then that wheel is transmitting no force whatsoever to the LSD. A locker is different than an LSD, and physicly locks the axles together, so it is possible to drive with only one half shaft in a locker equiped vehicle.
Originally posted by: iamwiz82
You are right, if the brake job is done on an UNBROKEN axle is completed, it wont come out. But if the caliper was removed on an axle in a solid axle design that was snapped, there would be noting to stop the axle from sliding out. However, the caliper will hold the axle in.
Can you explain why a caliper would NOT hold a broken shaft in?
The axles in some vehicles are held into the diff with a "c" clip. If that C clip breaks, the axle will slide right out of the axle tube. The only thing that would be holding it into the vehicle in that case would be the caliper and rotor. Since the axle tube is usually not large enough to let the axle fall enough for the rotor to come out of the caliper (if the axle snapped at the splines), the axle should stay put. but as above, you will stop without a locker in the diff. If you drive like that (IF you can drive like that) you will distroy the axle, tube, rotor, caliper, and just about everything else :p But the vast majority of the vehicles with those axles are drum brakes. In that case, watch as your axle and wheel pass you on the road.
Originally posted by: Jemcam
Trivia question:
What domestic muscle car in the 1960's had a rear transaxle, yet was a front engine car? (hint: it was a GM)
The polaris. but I didn't think it was ever produced.

<edit>
man, getting the formatting correct when quoting 5 people is a major pain.
 

Evadman

Administrator Emeritus<br>Elite Member
Feb 18, 2001
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Originally posted by: Garfang
I did not write that. Thank you.

I noticed :) I was using your header to cut and paste. Quoting 5 people is a pain :p. You read and replied before I was even done proofreading it. Sorry about that. no offence was meant to you or iamwiz82. My bad.

 

Soybomb

Diamond Member
Jun 30, 2000
9,506
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OMG YOUR CAR WILL EXPLODE!!!

Okay so theres a lot of misinformation in this thread and its gotten off track. Your car will stop moving forward. Most likely with a very loud scary noise. You may get the shaft banging around hitting things but I don't know anyone who'se had that happen and I know alot people with broken joints.
 

Pepsi90919

Lifer
Oct 9, 1999
25,162
1
81
Originally posted by: Stratum9
I drove most of the Alaskan Highway with a bad CV Joint. It completly went about 10 miles outside of White Horse in the Yukon. I knew it happend because I lost most of my braking power, the pedal went to the floor. But I kept driving another 70 miles until I got to Hains Junction because this was one of those many long stretches of road where there is absolutely nothing in sight.

When I stopped at a gas station in Hains Junction -- with the little brakes I had left -- the front wheel well had smoke coming out of it. Luckily the gas station was also a restaurant and motel. The next day there was a garage in town that had the parts I needed to get me back on the road headed towards home in South Central Alaska.

The entire axle had to be replaced because the bearings got so hot it melted everything including the brake lines and such.

BTW: All this happened while pulling a U-haul trailer with the car.

there's no way you could have come to the conclusion that your brakes failed BECAUSE the cv joint let go. that's not the way that works.
 

Thegonagle

Diamond Member
Jun 8, 2000
9,773
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71
Originally posted by: Soybomb
OMG YOUR CAR WILL EXPLODE!!!

Okay so theres a lot of misinformation in this thread and its gotten off track. Your car will stop moving forward. Most likely with a very loud scary noise. You may get the shaft banging around hitting things but I don't know anyone who'se had that happen and I know alot people with broken joints.

Yeah, true. The thing is, it will probably fail completely while you're turning out onto a highway in front of a semi-truck, a compact SUV towing a Winnebago, a cell-phone-soccer-mom in a full size SUV, or some other large vehicle that, for some reason or another, won't stop in time to avoid pancaking you.

So, just get ?em fixed, OK?
 

Pepsi90919

Lifer
Oct 9, 1999
25,162
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81
i'm on my 2nd left and 4th right axle on my honda. the OEM ones went bad, and the remans on the right side all died within 2 weeks :|
 

Zenmervolt

Elite member
Oct 22, 2000
24,514
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91
Originally posted by: Evadman
Originally posted by: Jemcam
Trivia question:
What domestic muscle car in the 1960's had a rear transaxle, yet was a front engine car? (hint: it was a GM)
The polaris. but I didn't think it was ever produced.

<edit>
man, getting the formatting correct when quoting 5 people is a major pain.
Wrong. Polaris was rear-engined. (Essentially a Corvair with Pontiac badging from the photos I've seen of the prototypes.) I'm pretty sure that the car was the four-cylinder Tempest, but I've not been able to confirm.

ZV
 

Thegonagle

Diamond Member
Jun 8, 2000
9,773
0
71
Originally posted by: Pepsi90919
i'm on my 2nd left and 4th right axle on my honda. the OEM ones went bad, and the remans on the right side all died within 2 weeks :|

The OEM ones are good for 90,000 miles. The rebuilts aren't. Best thing for a Honda is to have the dealership replace just the boot as soon as you notice it's torn. Of course, you need to be the type of car-person who looks out for that kind of thing. 3000 mile oil changes are good for this type of thing.
 

Evadman

Administrator Emeritus<br>Elite Member
Feb 18, 2001
30,990
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Originally posted by: Zenmervolt Wrong. Polaris was rear-engined. (Essentially a Corvair with Pontiac badging from the photos I've seen of the prototypes.) I'm pretty sure that the car was the four-cylinder Tempest, but I've not been able to confirm.

ZV

Well, if the engine is in the back, and it is rear wheel drive, does it not have a transaxle? :p. but it was not front engine. After you poted that, I went lookin' around on google, and found that you are correct. the Tempest was front engine, rear transaxle drive.

The Tempest was introduced in 1961... <snip> ...to make the drivetrain tunnel even less intrusive, Pontiac stuck the transmission in the back of the car, in unit with the differential. So, like the Corvair, the Tempest had a transaxle in the rear. The engine remained up front.

From here

<edit>
lol, that site has info on the polaris as well. You know your older cars ZV :)
 
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