transfer case noise

I have a 1975 CJ5, staright 6 232, Dana 20 transfer case, Dana 44 rear and Dana 30 front. It's all stock and only 40 thousand original miles. I just put a HEI distributor in her and with a rebuilt carb, K&N air assembly and new exhaust she runs like an absolute dream. My only problem is at high speeds there is a grating/metallic rattling noise at high speeds coming from the trannsfer case. All fluids were drained and refilled in both the tranny and transfer case and everything checked out excellent, it's just an annoying noise. I was told that the u-joint could be worn or need replacing and that would solve the vibration problem. The same guy also told me that if I replaced the u-joint detup with a cv-joint setup it would be even better. Is this true and if so, how difficult/expensive a job is it? You all have been a great resource in the past and i am hoping for some more wisdom in this dept.

 

could be the linkage worn or loose that goes to the transfer case.at higher speeds its not uncommon to pick up some vibrations and loose linkage will start vibrating.it would be a good idea to check all your u-joints also.

 

Make sure the front axle is completely disengaged and the hubs are in the free position?

 

Just an FYI - You image link doesn't work. Here is the correct link. I hope you solve to problem, but you have a really good looking CJ.


http://i113.photobucket.com/albums/n231/joshuatrout/SNC10011.jpg

 

You really shouldn't need the CV joint. Check all your U-joints and slip yokes. If either is bad or dry they do tend to raise cane at different speeds. I just replaced my front slip yoke because it vibrated at speed, if I had my hubs locked in. Lamar gave a good tip about the 4X shifters rattling. You might try grabbing them while your driving to see if this quiets your noise. On the CV joint, it won't be cheap and it will reduce the length of your drive shaft. It doesn't look like you run much lift so I don't see much benefit. By the way, that is a sweet looking Jeep.

 

Thanks for the tip and the compliments on the jeep. I tried your suggestion and yes, moving the 4x shifter does eliminate the noise at speed but as soon as you let it rest slack it returns. i am going to check the yoke and joints and grease where necessary and avoid any expensive non-stock upgrade if possible.

 

Anti-rattle spring?

 

Or stretch a glove over both shifters, that's what I did on an old International 4X4 years ago...