87 YJ rear universal joint

[Mint 98 TJ SPORT]

A friend of mine has an 87 YJ with body lift and lift springs, 35" BFG krawlers. It's off road use only, has had it for years and the 35's on it for about two years. In the last six months he has dropped the rear u joint out twice when wheeling bc the clips keep pulling out/ shearing off some of the screws that hold them in. Most of his wheeling is crawling up over the mtn in behind his property so not usually excessive on the gas pedal. The angle on his rear driveshaft doesn't appear much different than my TJ. Looking for some opinions on what might be the cause of this happening?
Thanks

[bill richards]

If the screws are being sheared off, the yoke is definitely binding.
Is it still spring under? If spring over, definitely axle wrap.
Make sure the spring ubolts are tight. The springs could be just weak too. Any broken springs?
An antiwrap bar would likely help.

Bandaids would be, adding a stiffer main leaf to the spring pack which will limit flex. Could try to remove some material in the yokes to allow them a bit more room before binding... at the expense of strength.

Bill

[bill richards]

Also... In the rare case this is an automatic, stand on the break and push the gas to see how much the pinion rotates. Do not put your head in front of a tire! Bad times ahead.

If it's a manual, maybe try to chock the wheels to immobilize them. I'd recommend using the e-brake... but yeah... "Jeep".

Bill

[Enos]

Aug 31, 2016 9:13:26 GMT -4 bill richards said:

I'd recommend using the e-brake... but yeah... "Jeep".

Ha! You've got that right!

[Mint 98 TJ SPORT]

Aug 31, 2016 9:07:28 GMT -4 bill richards said:

If the screws are being sheared off, the yoke is definitely binding.
Is it still spring under? If spring over, definitely axle wrap.
Make sure the spring ubolts are tight. The springs could be just weak too. Any broken springs?
An antiwrap bar would likely help.

Bandaids would be, adding a stiffer main leaf to the spring pack which will limit flex. Could try to remove some material in the yokes to allow them a bit more room before binding... at the expense of strength.

Bill

The jeep is spring under and springs aren't broken but bent, remembered that after I put the original post on...the rear springs are bent - the main leaf is bent just past the end of the leaf pack, as a result of a bit of a harsh drop into a low spot when wheeling.He's been looking for replacement springs but has managed to pick any up. Would the bent springs cause the rear axle issue he is having? If so I'll pass on that he needs to stop procrastinating and replace the bent springs...and Thanks for the time post the info

[bill richards]

Definitely wouldn't help. Would also change the pinion angle.

Bill

[Mint 98 TJ SPORT]

Thanks for the input Bill. I'll pass along that if replacing the bent spring and making sure the spring u bolts are tight doesn't get rid of the problem then maybe the next step would be the antiwrap bar. Thanks again...