Clanks/Clicks on hard acceleration

[mhariush]

My 2008 957 150k miles, has developed a clicking, almost ratcheting sound on hard acceleration, mostly from slow or stand still, like getting out of a light fast, but also sometimes when hitting the accelerator hard when in motion.

It almost sounds a little like a CV axel mixed with a ratchet strap getting tightened and I can feel it in the car. But since it's only on acceleration and not in turns I don't think it's the axels. It seems like its something in the transfer case area? Maybe the stepper motor?

Any thoughts on where to start here? If it's the transfer case that sounds expensive-ish, and maybe not worth going down that road? I also now have a stuck thermostat or something causing a check engine and a non working temp gauge.

[Steve108]

Have you already experienced the driveshaft carrier bearing failure? I'd describe that as more of a thumping, but otherwise acceleration is when and t-case is about where you hear it. You definitely have enough miles for that to go if it hasn't already.

[mhariush]

yes, I've had the drive shaft fail twice, once on a 955 and once on this 957. And that is def more of a thump sound yes.

This is more clicking sound.

how often do these transfer cases go bad? is it worth getting a used one and swap in?

the car also has a coolant error, no temp gauge and it appears the thermostat is stuck open. I have replaced both the temp sensors and they worked for a brief moment.

It seems like the transmission might need to be removed to access the thermostat housing on this V6 engine.

It could also use some new struts at the front.

And I just replaced the driver side window motor.

Maybe it's just too many things happening right now?