speed dependent knock?? Not U-joints...

[JStieger]

Lately, I have been trying to chase a speed dependent low pitched knocking sound.

I replaced the u-joints on my front drive shaft about 2 months ago due to similar symptons (except a tick-tick sound) as well as obviously blown seals. So today I decided to catch up on some preventative maintenance and replaced my rear drive shaft joints with aftermarket greasable joints as they were starting to look pretty worn too. This job went well and was pretty straightforward. As part of the job I felt for play in the transfer case slip splines, carrier bearing, drive shaft slip splines, and rear pinion. All felt normal with no clunking or out of plane movement. I then went for a test drive and the low speed, speed dependent knock is still there!

I push in the clutch and it seems that the knocking seems to go away slightly. Hard to say over the engine and road noise though. The sound volume is road speed dependent and the sound only happens on low speed deceleration.

Any ideas? Frankly, I don't know how long it's been there as lately I have been driving with the radio off to hear the singing turbo...

BTW I am glad my new Bilsteins are coming in Monday from Geno's. I noticed today that all my shocks had fluid leaking from them