Chasing a gear rattle.
 

Hey Folks,

I was hoping someone outthere may have come across something like what I am experiencing after a Hemi conversion. I know we all use different combos of parts so maybe someone has done something close to what I have in my Jeep.

Basically the build performs great, Smooth and powerful around town and back roads.(have not gone off-road yet) Its not until I get to the highway that I have concerns. up around 65 - 80 mph there is a change in the sound of the jeep, Has a bit of a growl. I would say a hum but that is too soft for what I describing. Anyway.. while that is present, it is not the reason I am posting.
My main concern is a chatter that I hear only when I am at highway speeds and in 6th gear during decel... The scenario would be cruising at ~70mph and then having to get off the gas due to a slower vehicle but not need the brake. As the rpms drop pass 2500 I start to hear this gear chatter. Not sure where it is coming from yet. It is not as present when the vehicle is cold and can be hear in 5th gear also as the I drive it longer. I found that during the same scenario but didnt want to keep dropping 6th into that low rpm range. The chatter is nonexistent when I perform the same scenario in 4x4. Completely quiet.

I am planning on removing the front drive shaft to see if anything changes but I am just guessing at this point.

I could use some guidance if anyone has dealt with this before.

Build details are below and a link to a video with the chatter.

Drive Train:
Engine: 5.7L Hemi
Transmision: Getrag 238
T-Case: Atlas II 4.3:1
Drive Shafts: Axle Exchange Drive shafts (double Cardan at the TC)
Front Axle:Dana 30, 4.88 Gears, Eaton E-Locker (sleeves and gussets)
Rear Axle:Dana 44, 4.88 Gears, Eaton TrueTrac
Tires: BFG All-Terrain 37x12.5x17

For your listening pleasure:


Thanks in advance for any help