Bad chirp coming from rear end. Easy route was to change fluid-done! Gears looked fresh and solid, but this did not solve the chirping!

Truck info-98 ram 1500 5.9 auto.

No throttle and rolling slowly=chirp! Chirping frequency increases with speed of vehicle. Strong throttle=no chirp as I reach desired speed chirping begins. Let off throttle or increase throttle=no chirp.

Also, fixed infamous death wobble, but now rear death wobble. At higher speeds rear end will jump lanes!

Next infamous dodge thunk when putting in Drive or reverse. Strange part is though when I am in traffic and truck wants to shift from 2nd to 3rd at approximately 18-21mph, I get wicked thunk. From underneath when putting it in gear thunk seams to be from rear of transfer case.

Could all three of these be all tied together? Here is the order of how these three things happened. Noticed thunk, then rear jumping, then chirping. Most annoying is definitely the chirping.

Any help would be awesome

 

Think I would have a look at the u-joints in the rear shaft.

2 or 4 wheel drive?

 

Yeah we do need to know if it's 4x4 or not. Have you inspected or replaced the U-joints, as mentioned?

I used to have a bad chirp, very much a rubber tire type chirp, and I couldn't pinpoint it for the longest time. I even rode in the truck bed while a friend drive me around the neighborhood so I could get an outside perspective on where it was coming from. I never did narrow it down to front or rear.

I suspected U-joints but luckily I made a transfer case switch before randomly replacing parts. What I was doing was putting a 1998 Durango transfer case in my 1998 Ram. I wanted the full time 4x4 capability. Part of the swap was to fully engage the front axle since the transfer case had it's own diff. Once the vacuum actuator was deleted from the front axle, the chirp went away.

I suspect there was a vacuum leak and conflict at the transfer case and based on engine RPM and vacuum, the 4x4 was engaging in and out at both the axle and the transfer case. This likely meant the chirp was from the front, but if the transfer case was going in and out of neutral there may have been some thunks as the rear drive shaft engaged again.

 

Sorry about missing that, it is a 4x4. I have positioned myself next to and under the truck to listen for the chirp. It is definitely the rear end. I was just under the truck and I have zero play on both ends of the driveshaft u-joints. Sounds like from the differential, when I changed the fluid the gears looked great. Could it be the pinion? Strange thing to this is that there is zero play at the driveshaft point.

What could explain the chirping sound disappearing when throttling or letting off the throttle. I did play around today when rolling slowly and the chirp begins. I would pop it in neutral while rolling and I noticed the chirp would go away.

 

You are putting a load on the driveline when accelerating. Apparently, it only chirps under specific conditions. If you can tell which end it is coming from, I would drop the shaft, and check the joints off the truck. One may be binding, instead of being loose.

 

For sh*** and giggles I sprayed my leaf springs with some lithium grease considering I am limited working out of a hotel parking lot! That seem to remove the chirp. If springs are shot I guess that would explain the rear end hop too.
If springs are truly shot could that being causing the shift clunk I seem to be getting while traveling at slow speeds in traffic? The clunk only happens while traveling slow (in traffic) and shifting from 2nd to 3rd at approximately 20 mph.
I do get the notorious clunk when putting in drive and reverse and I have identified that as being on the rear side of the transfer case. The tranny was rebuilt but not the case. Could this be signs of it needing rebuilt? I never had the clunk at anytime until recently when I noticed the chirp.

What leaf springs does anyone recommend?