When in 4X4 my truck will make loud snapping noise coming from the front end. It only happens when it is under a lot of torque, and it does it either turning or going straight. It is really bad if I use 4X4 to back my camper up on grass. When looking things over tonight the only thing I can see that might be an issue is the transfer case. With the truck in 2wd and turned off I can not rotate the front drive shaft. My buddy's 2000 you can turn his front drive shaft just fine by hand in 2wd. What could be causing this issue?

 

Check the u-joints on the drive shaft and the ones on the front axle. Before blaming the Transfer case. On my wifes 96 4x4 the vacum lines that engage the front axle had a leak, causing it not to fully disengage the front end. the plug for the vac lines on top of the transfer case is where it was leaking on her truck. If i remeber right there is four vac lines that come out of the transfer case abd run down to the front axle. But that was on a 96 dont know if it the same on a 02.

 

Just went thru the same scenario as yourself.

Turns out it was one of the u-joints in the double cardon joint on the front drive shaft. I got the snapping noise as well what sounded like a chain dangling on the road as you drove (a tinkling sound)

Ended up being the front side joint. While I had it out, I replaced all 3 joints as well as the centering bearing in the cardon joint. Good to go for another 100,000 miles.

Jeff

 

2000 had the CAD, Central Axle Disconnect.
2002.5 doesn't, so the front driveshaft is always connected and turning.

I second the verdict that it is the CV joint, the double cardan where it connects to the transfer case.


phox

 

Thanks, for all of the information this helps out a lot. It looks like there are two u-joints in front of the transfer case and one on the axle. Should I replace all three u-joints as well as the CV joint/double cardan. What does the CV joint and double cardan look like? Does anyone have any pics?

 

Double Cardan CV Joint



phox

 

Here's a couple pages with exploded views, rebuild tips.

http://www.rblewis.net/personal/bronco/driveshaft/

http://www.pavementsucks.com/tech/doublecardan.php


phox