00" Sierra 1500 Z71, Weird "clunk"

[Fastturbo]

I've had this truck for about a year, for the past few months when I step on the gas to take off from a stop, theres a clunk noise from the rear like theres too much play somewhere. The rear diff is fine, what else could this be.

 

 

Thanks,

 

 

Matt

[VR021302]

u-joints is the most likely problem

[Fastturbo]

u-joints is the most likely problem

 

I saw also a slip yoke needing maintenance would produce a similar condition?

 

Just trying to narrow it down.

 

 

Matt

[BuckFeverZ]

u-joints is the most likely problem

 

I saw also a slip yoke needing maintenance would produce a similar condition?

 

Just trying to narrow it down.

 

 

Matt

 

 

You said it.

[MS3DALE]

Slip yoke.

[Fastturbo]

Slip yoke.

 

I'll service that, seems easy enough, thanks!

[MS3DALE]

Slip yoke.

 

I'll service that, seems easy enough, thanks!

 

 

You might have to replace it,There is a bulletin on this issue and replacing it is the correction.

Although you could try greasing the splines first.

[Gryphon]

I had the same issue. Replaced both u-joints just in case with heavy duty units, and greased the splines of the slip yoke with marine grease. Marine grease won't wash off like other greases will and is much more tacky. It's dark blue in color and is purported to be a fix for this issue (besides replacing the slip yoke).

[ukrkoz]

another thing they should have recalled, but hey, that's why they are on a brink now...

 

yes, you can "exercise" rusty slip yoke with GM magic lube with PTFA. problem will come back in about a month or 2. now, keep in mind, because it's binding with transmission output shaft, you'll either screw the shaft bearing, or will have to "exercise" it every time noise comes back.

 

exercising is official GM term for slip yoke and ISS.