clunking when in 4 wheel lock? What is causing it???

[ratchetmaster]

I have a 78 chevy PU and when I put it into 4 wheel drive, it makes a clunking noise . . . clunk clunk clunk . . . mostly when I turn. IT sounds like it is coming from the front right side. the clunk noise is almost like a "poping" noise.
One person said it was the T-case (203) and another person said it was the joint between the axle and the hub??

all ideas welcome.
thanks
tim

 

[85mudblazin]

check your front driveshaft and make sure it isnt binding, if its ok check out the axle u-joints and iff they look good then pop the cover and see if every thing is ok in there.

 

[AkMudr]

If it clunks mostly when you turn, I'd say its an inner axle ujoint..

Spicer Part # 5-760.

 

[ratchetmaster]

thanks for the reply

I put a new joint on the front of the front drive shaft but it has the wierd coupler on the t-case side . . . it didn't move very smoothly when I wiggled it before I put it in . . . could that be the binding you are asking about? How is that fixed??
Thanks

 

[75-K5]

I hope you aren't driving it on dry hard pavement while in LOCK. That is bad news bears.

 

[AkMudr]

Honestly if its a front driveshaft and its somethin wrong with the "CV" oart of the front shaft.... yer better off takin it to a driveshaft shop and lettin them rebuild it.

That what I always did. Not that I didnt trust my work but its just easier that way.

 

[ratchetmaster]

I hope you aren't driving it on dry hard pavement while in LOCK. That is bad news bears.

Well . . . I hate to admit it, but that is exactly what I did . . .

this is my first 4X4 and as you have now guessed, I don't know what the heck I am doing here . . . lol

soo . . . I don't want to do that, right?? there are 4 settings on my t-case shifter . . . L, L lock H and H lock. It is a full time 4X4 so when is it actually in 4 wheel drive? All the time?? What exactly does "lock" mean and do??

on the drive line topic, that wierd ujoint coupler by the t-case is something I definitely will not mess with . . . but regular u-joints are simple enough.

 

[sleeper_dave]

when you put it in lock the front axle and rear axle spin at the same speed. When you turn, the front axle has to move faster. Since it can't, it binds, then the tires slip or something breaks. Don't ever use lock on dry pavement.

It's in 4x4 all the time, but when it's not in lock in theory one stuck tire could keep you from moving.

when i had my '78 i got a 4x2 conversion kit and manual locking hubs so that it was only in 4x4 when i put it in lock. That saves wear on the front end and saves gas.

 

[ratchetmaster]

well, silly me . . .

I sure hope i didn't damage anything . . . I didn't drive it much like that, just up the block and back.

What might I have damaged if it is damaged??

It only makes the noise when in lock on dry pavement so maybe their isn't anything wrong . . . just it telling me that "I" am doing something wrong!!!

Thanks for the help.
Tim

 

[sleeper_dave]

if you broke something you'd know it.

my guess as to the first thing to go would be the chain in the transfer case. I had one stretch and start jumping teeth on me.