"Chirp" when taking off from stop. Something slipping?

[C.Steele]

I have a 2000 Silverado 1500 4x4 with a 4.8L - Automatic trans

When I take off from a stop I sometimes hear a "chirp" like something is slipping or rubbing metal on metal. It sounds like a big sound not small if that makes sense. Kind of a hollow metal rubbing on metal sound. Best I can describe it.

When I pull my boat it does it all the time. When not towing it does it maybe 40-50% of the time. It sounds like it's coming somewhere from the center to the rear. Definitely not the engine or front area.

I have looked underneath and I don't see anything obvious. Does this sound familiar to anyone? Looking for ideas of where to start narrowing things down here. U-Joint? Rear end (please no)? Suspension?

I have no clue where to start looking. Thanks for any advice.
Chris

[777stickman]

Are your rear brakes drum or disk? If drum you may want to look there 1st. U-joints could also be an issue.

[kahjdh]

Prob the slip yoke....

[denco]

My 2001 has done this since new.
Mine also has a clunk from the drveshaft, pop from the muffler and ticking engine.
Love it!

[C.Steele]

Originally Posted by kahjdh

Prob the slip yoke....

I did see a TSB online about the slip yoke producing a "squawk" when taking off from a stop. Maybe that is it.

Is there a way I can check this? Is it possible it just needs lube? Is it something I could do myself?

I know nothing about a slip yoke. Matter of fact I'm not even sure where it is. I think it's at the end of the drive shaft coming from the transfer case? Thanks for any info.

[j cAT]

Originally Posted by C.Steele

I did see a TSB online about the slip yoke producing a "squawk" when taking off from a stop. Maybe that is it.

Is there a way I can check this? Is it possible it just needs lube? Is it something I could do myself?

I know nothing about a slip yoke. Matter of fact I'm not even sure where it is. I think it's at the end of the drive shaft coming from the transfer case? Thanks for any info.

I had this problem of slip yoke sticks and when starting from a stop especially when still cold . this was corrected back in 2003 on my 2000 5.3L 4X4 , when the dealer under warrantee replaced the tracII transfercase fluid.

since that time I replace this fluid and the transmission fluid every 30-40,ooo mi . the clunk has not returned and 10yrs with over 125,ooomi no failures or leaks.

trac II transfercase fluid is "only" at dealerships. If you have some lube jocky do it they can destroy your transfercase with the wrong fluid.

[kahjdh]

I did the flush and it didnt work, had to put the nickel plated yoke on.

[j cAT]

Originally Posted by kahjdh

I did the flush and it didnt work, had to put the nickel plated yoke on.

COULD BE the one that was on there was worn.

my clunking yoke was only at 30,ooomi .....

I knew it was the yoke cause I could spray the drive shaft with wd-40 and it would go away for a few weeks then come back..

[kahjdh]

yea, I bought mine with 94k on it already.

I tested it by taking the driveshaft off and drenching the yoke in auto trac then taking a test drive. Was quiet for a few miles so knew it was it.