GrassLakeRon
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B8200HST-DP , RC60-82h Mower Deck, Woods RB6 Rear Blade, Homemade Carry All
New Kubota B series pto shaft, squirrel is optional.
Big U-Joint
- Thread starter D2Cat
- Start date
Well yeah a CV joint is actually a double cardan .... without the rubber boot.
So we are all correct...
However If you walk into a jeep shop or 4WD shop and tell them you need a CV joint for your Jeep XJ front shaft they will laugh you out of the shop.
The commonly used terminology is double cardan joints for driveshafts and CV joints for front axles... especially front wheel drive cars and even VW bugs.
speaking of jeeps, some guys will use a double cardan joint on the back also along with a slip yoke eliminator... that way if you bust the rear shaft out in the woods you can use the front shaft in back.
double joint in back also helps with extreme driveshaft angles on lifted rigs.
gee, all I did when the rear driveshaft broke, was yank it out,lock hubs,go 4WH and drive away....
Go to Google.com and click on the "search by image" button on the right.
Drag image into box or click upload and search for the image file.
Google will return a list of images that match the one uploaded.
North Idaho Wolfman
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If you use google as your browser you can right click on an image and do the same thing.
Donystoy
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LX2610HSDCC, B/H, Loader, plus numerous other attachments. B7200 sold
This is what I have always known a CV joint to be. At least in the automotive industry. Not sure if they would use this style in large industrial applications. Making a rubber boot large enough and strong enough could be an issue. Besides, how much grease would you need.
They used the ball and cage style CV joints on a LOT of different stuff. Automotive especially (front and IRS rear usually). BUT they've started playing with them in high speed drive shafts as well in the last few years. I started to order one for the Mustang but decided against it, as at the time CV joints were still "new" for that application. Sure reduces vibration I'm told.
I play with them at work on a daily basis (Off road vehicles) and see how they typically fail. If they fail, it's gonna be a few major reasons. Boot tore and let dirt/water in (#1 cause) and/or excessive angle combined with load or shock load usually. Either breaks the cage and sends it through the boot eventually OR breaks the axle shaft off in a severe shock load. Those are the most common causes although there are considerably more.
The ball/cage style also tends to generate some heat due to friction and that is also dependent on the angle that the joint is asked to run at. "We" (you?) put a big lift kit on your rig and don't address the CV joint angles and then next thing you know, we're griping because the joints get hot and the boots swell. Some of the aftermarket (non oem) axles will tolerate a little more angle before they show signs of heat, but ideally if you're gonna lift it "that" much, it's better to go to a portal gear lift. Then you have 4, 6, 8, 10" of lift from the portals themselves, plus a gear reduction which significantly reduces the load on the axles transmission etc AND reduces the angle on the CV joints. Expensive to do the portals but worth it if you're gonna be in a lot of soft stuff especially. Also moves the tires outward a little, which gives you room for bigger tires. We did a rzr a while back with 8" portals with a lift, on 55" tires. That was a big dude, I'm 6'7" and it was hard for me to get into it!
I play with them at work on a daily basis (Off road vehicles) and see how they typically fail. If they fail, it's gonna be a few major reasons. Boot tore and let dirt/water in (#1 cause) and/or excessive angle combined with load or shock load usually. Either breaks the cage and sends it through the boot eventually OR breaks the axle shaft off in a severe shock load. Those are the most common causes although there are considerably more.
The ball/cage style also tends to generate some heat due to friction and that is also dependent on the angle that the joint is asked to run at. "We" (you?) put a big lift kit on your rig and don't address the CV joint angles and then next thing you know, we're griping because the joints get hot and the boots swell. Some of the aftermarket (non oem) axles will tolerate a little more angle before they show signs of heat, but ideally if you're gonna lift it "that" much, it's better to go to a portal gear lift. Then you have 4, 6, 8, 10" of lift from the portals themselves, plus a gear reduction which significantly reduces the load on the axles transmission etc AND reduces the angle on the CV joints. Expensive to do the portals but worth it if you're gonna be in a lot of soft stuff especially. Also moves the tires outward a little, which gives you room for bigger tires. We did a rzr a while back with 8" portals with a lift, on 55" tires. That was a big dude, I'm 6'7" and it was hard for me to get into it!
Runs With Scissors
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In my shop, we call that a "Big Ole Double U-Joint"
A Cardigan.......
Double Cardigan.....
Help......I cant get this out of my head.........
A Cardigan.......
Double Cardigan.....
and-going back a number of years when I had to do factory training (was discussed briefly at kubota training but much more in depth with Yamaha training), a double cardan is not a cv joint-it is simply 2 u-joints back to back, which gives the ability to get a little more angle between the driving and driven member. U-joints, even in a double cardan style, still are not constant velocity (CV). As the U joint goes through a rotation, and the drive and driven member are at an angle to each other, the shafts change speed slightly, even with a double cardan. With a CV, they do not change speed.
On a u joint shaft, there is usually 2 joints, and it's best that they're at equal and opposite angles between drive and driven--this cancels out vibration from each end. Double cardan somewhat accomplishes that but not nearly as well as cv which can become important in instances, such as a drive axle used in a vehicle-where the inner u-joint (at the differential) does not change angle nearly as much as the outer joint does; which causes a "surging" feel when one joint is at a different angle from the other. CV joint solves this.
as I said earlier CV joints are finding their way into race cars and a lot of street cars as well. My 22 Mustang has cv joints on the drive shaft. My other mustang (which just sold), I looked at putting a CV style drive shaft in it, but had concerns of strength, heat, cost and speed. At eleveated speeds the grease gets forced out against the boot, makes the boot heavier, which swells it, the joint gets hot, etc. And, it woudl've been about $2000 at the time for a CV shaft, so I just put a Ujoint shaft in it at $675, and had to play with the drive shaft angles to get rid of the vibration (me being picky....). I asked the shaft shop about doing a CV shaft for the race car. They said sure, gonna be about $1400. Then they started asking questions, we got to the shaft speed and they just laughed and said "u joints are your best option". At 9100 RPM the boots would get really sketchy they said.....
On a u joint shaft, there is usually 2 joints, and it's best that they're at equal and opposite angles between drive and driven--this cancels out vibration from each end. Double cardan somewhat accomplishes that but not nearly as well as cv which can become important in instances, such as a drive axle used in a vehicle-where the inner u-joint (at the differential) does not change angle nearly as much as the outer joint does; which causes a "surging" feel when one joint is at a different angle from the other. CV joint solves this.
as I said earlier CV joints are finding their way into race cars and a lot of street cars as well. My 22 Mustang has cv joints on the drive shaft. My other mustang (which just sold), I looked at putting a CV style drive shaft in it, but had concerns of strength, heat, cost and speed. At eleveated speeds the grease gets forced out against the boot, makes the boot heavier, which swells it, the joint gets hot, etc. And, it woudl've been about $2000 at the time for a CV shaft, so I just put a Ujoint shaft in it at $675, and had to play with the drive shaft angles to get rid of the vibration (me being picky....). I asked the shaft shop about doing a CV shaft for the race car. They said sure, gonna be about $1400. Then they started asking questions, we got to the shaft speed and they just laughed and said "u joints are your best option". At 9100 RPM the boots would get really sketchy they said.....