exploding UJ's

[donkeychomp]

New years eve one of the rear UJ's went bang, so I tootled about with front wheel drive for a short while...then that one went too! Replaced both props with excellent second hand ones now the rear is going again! Running a 413 with the 413 transfer case (I know) and 31" tyres. Is the transfer case causing this problem? Any ideas?

Cheers, Alex.

[Highlander]

Is it SPOA?

prop angles too severe?

[ScottieJ]

Firstly next time you replace them, fit brand new UJs to your existing props, they'll last longer

Secondly how much lift are you running? is it still SPUA or has it been changed to SPOA?

Has the transferbox got the original mounts fitted?

Ujs dont last forever however there are a number of things that can increase wear and cause them to fail prematurely

1. Is there any play in the pinion bearing in the rear diff?
2. Is there any excess movement in the slip yoke on the propshaft?
3. Is the SJ lifted quite high and the Propshafts running at quite a steep angle?
4. (getting a bit more technical) Are all the U-joints in phase i.e. the transfer box output and rear diff flange within 1-2 degrees of each other.

Front diff flange should be at 10 degrees, rear at 5 degrees and the tcase outputs should be at 5 degrees with the tbox higher at the front.

[donkeychomp]

It's got a 3" shackle lift, that's it. I'll be checking the diffs tomorrow.

Thanks for the tips!

[ScottieJ]

If its got 3" shackles then your driveline angles will be out? Wouldn't be surprised if it handles like a boat either no offence inteneded but that's a bit of an excessive shackle lift, I would advise cutting them down, to 90-100mm hole centres maximum. You'll find it drives a lot better.

[twiss]

Yeah shackles are really terrible.
I had 3" ones on mine and it was awful.
Best bet is to get some 2" lift springs or add a leaves...
Then you can cut the shackles down to 1" lift and still be at the same height

[donkeychomp]

After much head scratching and a team of dedicated idiots, sorry, fellow off roaders, it's going to get a Vitara engine. Diffs are fine, and it seems the larger tyres are putting too much stress on the props so more power might be the way. More power is always good in my book. Oh and 'Piglet' handles like a dream, 32mm spacers help!

[ScottieJ]

Sorry but more power is actually just going to make it worse. The only thing that will reduce the strain on the props is lower ratio diffs. However I don't think that is your problem, you could be getting a lot of axle wrap if your springs are tired. If you get someone to watch the rear diff as you pull away does the diff tilt up?

If yes then I would advise getting some new springs and running shorter shackles.

[Henry]

Spend your few hundred quid on engine and all the gubbins on a set of add a leafs from Dave at llama 4x4.


I bet your 3" lift shackles are now pretty much back to standard height. Look at the front of your truck, the front springs will be pushing down at the front, pushing your diff flange (love that word) up, giving you bad angles.



But hey what do i know