Author Topic: NP205 Question  (Read 2576 times)

Offline Militiaman55

  • Newbie
  • Posts: 46
  • 74 K10 Cheyenne
NP205 Question
« on: November 26, 2016, 01:29:24 AM »
Hello All!

74 K10, 350/TH350/NP205.  D44 front, 12 bolt rear

I've noticed some noise coming from what I suspect is my front output shaft bearings while running in 4WD. I believe this because I can leave the hubs and axles locked up and run it in 2WD with zero nose. Or does that mean something else is wrong?  When in 4WD, It simply sounds like a smooth grinding coming from the front. Aside from that, it works in high and low like normal.

If the bearings are the issue, my question is, can I get to everything i need from the outside of the case to replace the bearing(s), or do I need to remove the case from the truck in order to open and fix the issue?

Thanks for any help,

Rob

Offline Captain Swampy

  • Junior Member
  • ***
  • Posts: 504
  • Wisconsin
Re: NP205 Question
« Reply #1 on: November 26, 2016, 01:15:57 PM »
I would remove the front drive shaft. You can then check the u-joints in it, the pinion of the axle, and the output shaft. Check them for play and rotate them to see how they feel. You could also take a ride with unlocked hubs in 4wd with the driveshaft out and see if it still makes the noise. I haven't had a 205 apart, so I can't help with that. Take a look in the tech section.
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


http://forum.73-87chevytrucks.com/smforum/index.php?topic=32209.0

Offline Militiaman55

  • Newbie
  • Posts: 46
  • 74 K10 Cheyenne
Re: NP205 Question
« Reply #2 on: November 26, 2016, 09:23:14 PM »
Thanks for the great suggestions to help me figure out where the issue is.

I appreciate it!

Rob

Offline 75gmck25

  • Frequent Member
  • **
  • Posts: 423
  • 1975 GMC K25 Camper Special, 350/TH350/NP203
Re: NP205 Question
« Reply #3 on: January 15, 2017, 09:43:56 PM »
If you have a 74 K10, 350/TH350/NP205 combination, I don't think is was not one of the factory configurations in 1974.  With the 350/TH350 in 1974 it should have an NP203.  If someone swapped out the transfer case, did they get all the other correct parts to go along with it?

Bruce

Offline roundhouse

  • Senior Member
  • ****
  • Posts: 1474
  • Newbie
Re: NP205 Question
« Reply #4 on: January 15, 2017, 10:42:55 PM »
Yep
Pull the front shaft and check it good
Then you can spin the pinion
And spin the axle shafts
And spin the t case output shaft

It could be the t case but probably the CV joints in the driveshaft or maybe the U joints at the wheel end of the axle shafts


Sent from my iPhone using Tapatalk

Offline Militiaman55

  • Newbie
  • Posts: 46
  • 74 K10 Cheyenne
Re: NP205 Question
« Reply #5 on: May 15, 2017, 11:21:49 PM »
Thanks for the info gents! 

I haven't had time to pull the shaft and do ant investigating yet, but the shaft is all brand new and freshly balanced, including the CV joints.  I was happy to pull the heavily worn, floppy one off, and replace it with an extended one.  When the truck was lifted 6" the original was left in place.

One thing I have noticed is when I'm all locked in 4 wheel drive and the front axel isn't working hard, its quiet as it should be.  When the front is pulling/working hard, like when I'm going through a deep sand wash or up a steep hill, that's when the noise is most prevalent.

The 205 was put in my the previous owner and it appears like all the necessary components are there.

Rob.