I went snowmobiling the other day and now have popping going on inside my front end when in 4wd and there is pressure on the drivetrain. I believe it is the CAD as I have already jacked up both sides, checked all 5 U joints and turned the driveshaft (Pinion feels tight and driveshaft turns with ease). All U joints look good and have no slop in them. The transfer case has very little slop as well. The only thing left is the CAD. I think the diaphragm inside the actuator has gone bad because I can suck on the side that pulls the CAD over onto the disconnected side and it holds the vacuum. If I suck on the other line, it does not hold vacuum. Is there anything else I'm missing?

Good thought, but no. The fork could not have still been moving after trying to get it to hold vacuum that long 

Ok replaced the actuator today... It was bad because it wouldn't hold vacuum on one side and the new one held it on both sides, but the popping noise has not gone away. My 4wd is working as it should - front and rear tires are pulling even when it does pop. Does anyone have any other thoughts? I'm thinking driver side U joint??

you still thinking  the noise is  'ringing'  from the   cad  housing?         If  so,     I'd  suspect the  passenger side  first.      Noise  will   bing down  those  shafts  and  come out   any ol place too.      But  to  come  clear  from the   drivers  side,  through the  differential,   and  resonating   out the  cad  housing  is   pushing it  a  little  far...    nothing is  impossible though!

 

 

Does  it  change  (noise)    any at all  if   turning  sharp,  or  driving  straight?    How  bout   reverse?  

It still sounds like it's coming from the front passenger side. Did some testing and man it hurts to hear it do it, but it seems like it does it most when there is pressure against the drivetrain (Shifting down for example) It clicks really fast just shifting down and going straight. It also does it when turning on pavement or slippery snow. The truck still does its hopping and "spins" the rear tires so it feels like everything is engaged, just some joint isn't happy.

If its a bad universal you should be able to get in there with a pry bar and find the culprit. Also keep in mind the univerals in the front axle are always turning, so while it is possible its only detectable in 4wheel drive its not likely.

All of the universals looked and felt tight. I wish someone else could hear it. It sounds like a set of small gears are stripping off when going fast. 

All of the universals looked and felt tight. I wish someone else could hear it. It sounds like a set of small gears are stripping off when going fast.

Could it be spider gears? How is oil look

Oil looked beautiful gold when I pulled the CAD. There weren't any flakes that I could see.

lets   narrow  the   sound down!

 

How  'fast'  is  the   individual  'clunks'     tell us   when  driving  say,  25 mph,   is  it   clunk-clunk-clunk,  evenly spaced? 

 

Then you say it sounds  like  a small gear  getting  buzzed off..     which to me  could  be  a high frequency  'rip'..

Weird. 

 

Other systems up front look good? Brakes? Ball joints? 

It is evenly spaced and not sparatic. The faster you drive, the faster the noise.

 

Brakes replaced last summer (About 12K on them) Ball joints replaced this summer (About 5K on them) It's really weird because this started out of the blue on black ice. I used 4 low to move trailers around during the summer, then the first nasty snowstorm while using 4wd and this started. There were not any abnormal loud pops like something broke and is now grinding apart.

 

I plan to do some diagnosing tomorrow by switching the vacuum lines on the CAD. That way when I put it in 4wd the transfer case will be locked in and the diff will turn, but the CAD will be out. If it makes the noise I can eliminate the cad and look at either diff, driveline, or T case. If I have it in 2wd the transfer will be disengaged but the CAD will be engaged. If it makes the noise then it can not be the transfer case. 

FOUND IT!!!!

Ok I was crawling around under it and could not find anything loose. I pulled on everything, pried on everything and still could not figure out what could be doing it. So I said screw it and pulled the front driveshaft out. Behold a U joint is out! Now it wasn't out like most I see where the needles are gone and it clunks, but rather it moves A LOT side to side inside the caps. Anyone ever seen this?? I will be going to a buddies house who has a vice to get the new one installed. I tried to do it in the parking lot by myself with a hammer and sockets, but could not get one of the caps to break loose. I'm hoping this is it!

yep.  been there!

when the needles   got chewed up,     the  resulting  abrasives   inside  the cross  ate up  the  inside of  the  caps, and  some off the ends  of  the cross.     Which  gave the  cross more clearance to   move.   I'll bet  the  end caps  are paper thin now.   Plus  you'll  find  the  ends  of  the cross  tapered, and or  rounded off.

 

Good  find!   lucky you found it before it  ate it's way into the  yoke!

Question: Should I go ahead and put a new centering ball kit in while I have it apart? I feel like it's a good idea - I don't want to tear into this thing again (I'm thinking about replacing the good U joint while I'm in there too)

 

On an unrelated note my brother and I discovered how much pressure a stock 05 intercooler can handle.... a little over 60 psi and it blew the side off!! Makes my repair seem cheap 

might as  well  do it   all  at  once.   Oh  btw,    I  found     a     guy  building   these  front  DS's   with   all genuine   spicer  parts..  and  upgrades  the  crosses  in   the  CV  joint (  larger)   1350 series.

For about   350.   It's  a  custom built,  custom length  for   various  lifted   trucks too.  (or stock length if  that's  what you need)  http://www.ebay.com/itm/250884928842?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

Just  in case  you  find  more  wear an tear in there!    Those  CV's  get  real  pricey  very fast.    Hopefully you  caught yours  before  it  takes more than the  ball kit!

Everything looks good inside! I will bookmark that for future reference though. Thank you. What are everyone's thoughts on the greaseable U joints (It greases through one of the caps not the center) Think it could help the joint live a long and healthy life or will cause problems?

grease zerk on  cap:   handy to grease no doubt.

 

They are  'out in the wind'..  and    they'll  be  sandblasted   in  short order,  they'll  be  eroded,  the  little ball will be gone..  the  grease gun  won't   seal against it..  and       every   piece of   wire, or  baling twine  will  be  magically  attracted to that little bugger...   Maybe  not   in  short order,  but  they  can be problematic over time.

 

My  'yota   is  all set  up with  those,  and   I  love-hate em!     Toyota  puts  a  little   sheetmetal shield  over all their   joints,   so    those  zerks  are  protected.  Just have to  take the shield off..     more time,  but   probably worth it.

Didn't want to leave this thread open ended. I got the u joints put in on Tuesday and the driveline back in last night. Talk about a pita to get the centering ball lined up with the driveline and a 2 new u joint!

I did get the greaseable style and was pleased to see this type of zerk. I don't think I'll have any trouble with it catching debris. (Plus it's protected by the skid plate)

Good to hear!

I know those double cardans can be a total *****... hope you been vaccinated!

the thread ibeen looking for. heres my issues. y2k ctd auto. the 4x4 light comes on but not as quick as it should sometimes. todayivacumed checked both sides of the accuator motor and it would not hold vacuum at all on either side. checked both lines coming in from the tc and both did hold vacuum i think i need the motor kit for a new diaphram ,sound right to you guys?

Edited March 10, 201510 yr by jigdog