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-   -   4x4 hard clunk in front when turning (https://67-72chevytrucks.com/vboard/showthread.php?t=594750)

namdlo 08-29-2013 11:05 PM

4x4 hard clunk in front when turning
 
I have a 74 Blazer with the 203 transfer case. When in 4 wheel drive I get a heavy clunk in the front end, right side, when turning left or right. Without the front driveshaft in no clunk. What is this?

chengny 08-29-2013 11:47 PM

Re: 4x4 hard clunk in front when turning
 
The steering can't be put hard over on dry pavement while in 4WD.

It is the case that when you are in 4WD, and on a turn, the front axle must spin at the same speed for both sides, however when turning, the outside wheel on the turn has to roll more than the inner wheel on the turn. This is what causes the "hop and skip" feeling, because the axle is turning, or at least trying to turn the same speed left and right, however the wheel on the outside has to turn more, so the hop and skip.

With the front drive shaft disconnected/disengaged the front tires are able to rotate at different speeds.

namdlo 08-29-2013 11:58 PM

Re: 4x4 hard clunk in front when turning
 
Is thee something wrong in the case or is that normal? Would the lock out hubs kit solve this?

chengny 08-30-2013 12:54 AM

Re: 4x4 hard clunk in front when turning
 
No it's normal - also begs the question; why even have 4WD engaged when on dry pavement.

If you happen to be in 4WD and will be using it again soon try to make wide turns (keeps the wheel speeds about equal and lessens the dragging of the outer tire). Even if you have to make a tight turn it won't immediately cause any severe damage - just don't do it alot.

motornut 08-30-2013 07:50 AM

Re: 4x4 hard clunk in front when turning
 
hows the front u joints?

KrazyRay 08-30-2013 09:59 AM

Re: 4x4 hard clunk in front when turning
 
You could have a worn out rubber mount on your crossmember allowing the t case to sag lower on the crossmember. This will cause the driveline to knock against the crossmember.

Ski-me 08-30-2013 11:05 AM

Re: 4x4 hard clunk in front when turning
 
Quote:

Originally Posted by motornut (Post 6245384)
hows the front u joints?

This is what I'm thinking too. Axle shaft u-joints (not the driveline u-joints.....although that wouldn't hurt either).


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