viscous coupling locked up

[ryanc8514]

so i learned today that if i replace my broken cv joints that they could blow again if my viscous coupling is locked up, which probably is because its so old...if it is locked then the cv joints will bind during turns which cause wear and eventually break them...does anyone know anything about this?

[rezdiver]

put the ebrake on, put the transmission in neutral, jack one front wheel off the ground, try and rotate the wheel, it should take some force but should turn. if it doesnt then your VC is bad and locked up.
the Viscous coupling is pretty easy to replace. a bit expensive but you may be able to find a good used one.

[Paul Grant]

I've got them used if you need one. Let me know if I can help you out.
Cheers,
Paul

paulgrant@mac.com

[ryanc8514]

i have tried that but the wheel continues to spin freely because the cv joints are blown...the last time i got stuck in the mud i looked under the truck and saw that my front and rear driveshafts were spinning, i guess im gonna get a 230 transfer case instead of a new viscous coupling since they are expensive, has anyone else had their vc lock up on them?

[Paul Grant]

I also have an LT 230 for sale if you want to go that route.

paulgrant@mac.com

[rezdiver]

well you cant diagnose a gunshot wound with out wiping the blood off first.....
fix your CV's then try the test. and if it works then you dont need a transfercase right.
and if your CV's are that blown then you will have a locked up VC, as your shafts will be spinning at different speeds which is normal to tell the VC to lock up.

[ryanc8514]

so i would just be wasting a set of cvs to test?

[rezdiver]

Hmmm, lets see, a couple of good used CV's from ebay for like a 100 bucks and 1/2 hour a side to put them in and maybe you will blow them( maybe not if your VC is still good), or a few hundred bucks for a Viscous coupling, a few hours to drop it in and you still need the CV's anyways. just dont take too many hard sharp turns and your CV's will be fine.
figure it out this way, the VC is supposed to lock up anyways if you start to slip a tire, so would that mean your CV's are going to break apart everytime your VC is doing what it is supposed to do when you are offroading.

[RageRover]

To really see if you need CV's or not, one would have to take the CV out and inspect it visually and look at the cage, the ball bearings, etc.. If everything checks out, than why waste a CV that ain't bad?

I bet there are other ways of diagnosing a locked up VC in the T-Case. But like Paul said, he has those LT-230's that were put in Disco's, and they typically came with CDL so, that is one project I have in mind if/when my T-Case is getting past its limits, is swap my BW T-Case for the LT-230, change the front shaft, and be done with it.

[onslow]

Originally Posted by ryanc8514

so i would just be wasting a set of cvs to test?

Stick a bar in a front propshaft uj and try to rotate the prop if it moves then the VC is ok (it does take some effort to turn it) if its immovable it must be deemed U/S and i would not advise you to drive the vehicle until replaced you can remove the front prop as a temporary measure to keep you an the road (with CV replaced) but take it steady as all the power will be going to the rear axle.

The CVs are the most likely failure point if the VC has failed it is unlikely to have blown both CV's

If a CV has failed do not drive the vehicle as if the CV fails they can break up and fragments can jam the steering if the become lodged in the cavity between the swivel and its housing this happened to me many years ago fortunatly it was at low speed and no one was hurt.

Cheers ONz

[Nomar]

I've got two RR Classics that I have converted to LT230s, one more to go.

If you offroad this truck, consider putting in some HD CVs and leaving the locked up tcase...

[ryanc8514]

i was considering doing that but i didnt know how well everything would turn out...u think the HD cvs will hold up?

[RageRover]

Hold up to an almost dead T-Case you mean? Possibly, but I wouldn't recommend it. Probably best to replace the T-Case, maybe with the LT-230 like Nomar did on his Classics and what I wanna do, and do the HD CV joints along with it and you'll have a stronger drivetrain. When/If you do the LT-230 swap, you'll have to get a shorter driveshaft, preferably one off of a Disco, so I was told. I dunno if you have to do something about the rear driveshaft, but overall a nice swap, plus the benefit of CDL.

[Sign Guy]

Does anyone have the procedure for swapping out the v/c? I did the bar test and moved the truck not the shaft! Forgot to mention that I don't have any power to the front wheels due to a half shaft being pulled.