Hi all,

While out trying a muddy hill at full throttle, I somehow managed to break my CV shaft in an odd way. :eek:

http://users.superford.org/ylobronc/mudmore/may02/cvshaft.jpg
http://users.superford.org/ylobronc/mudmore/may02/shaft.jpg

I didn't max out the angle on it or hit it on anything, just broke at 4-5K rpms in 2nd gear and low range.

Any of you experience this kind of breakage before? I'm wondering what caused it and what I can do to prevent it from happening again. I don't think I need to go to a 1350 CV just yet as I've never had any problems with the joints themselves. It's a high-angle CV shaft that's 1-1/2 yrs old built by AZ Drivelines and was retubed a couple inches longer about 8 months ago by a local driveline company.

in the pic, the cv looks fine, looks liek the ears on teh shaft went bye bye jiMMy

Without seeing the whole think did you loose a weight? In 2nd gear and low range given 5k rpm....the driveshaft isn't spinning that fast...my guess is axle wrap....or spring twitch causing excessive torque in the driveline...mine did something similiar....

Originally posted by coyote
Without seeing the whole think did you loose a weight? In 2nd gear and low range given 5k rpm....the driveshaft isn't spinning that fast...my guess is axle wrap....or spring twitch causing excessive torque in the driveline...mine did something similiar....

Axle wrap wont cause the cv to break.. unless you pointed the pinion straight down.. which is impossible going forward... Ive seen breaks like that before.. and my guess would be.. fatigue... it happens.. or the snap ring broke.. allowing the cap of the ujoint to walk out.. and in turn wipe out the yoke at the same time..but then again the trunion isnt beat up.. so i doubt that.. so my guess is fatigue..

It looks to me like the CV end bound up because of axle wrap or bouncing or whatever, possibly from a previous wheeling trip. The most common u-joint and CV joint breakage is by far binding.

It could have also been caused by the slipjoint running out of travel and smacking the CV into submission and it finally gave out.

Squash

I know the CV didn't bind and the slip didn't bottom out, I have checked both things when installed for the first time, both max angle and travel from full axle droop to full compression.

What has me suspect is the smooth surface on the top of the shaft and the left of the CV in the first pic, maybe a faulty weld?

Originally posted by ImKuNfusED


Axle wrap wont cause the cv to break.. unless you pointed the pinion straight down.. which is impossible going forward... Ive seen breaks like that before.. and my guess would be.. fatigue... it happens.. or the snap ring broke.. allowing the cap of the ujoint to walk out.. and in turn wipe out the yoke at the same time..but then again the trunion isnt beat up.. so i doubt that.. so my guess is fatigue..

Think again! When you get axle wrap, energy is absorbed when the spring bends. When it "unwraps" the torque applied to the shaft is multiplied.

Just looks like you broke the ears. Shit happens. It's not like it was really old. You'll have to have a new shaft made anyways so why not go 1350?

Originally posted by Dustball
What has me suspect is the smooth surface on the top of the shaft and the left of the CV in the first pic, maybe a faulty weld?

That was my first thought when I saw the pics. If ya got all the pieces you should be able to see the depth of the weld, if they did not get a good deep burn in it would definately fatigue and grenade.