The 'Old Slip Yoke Thud Issue'--I'm new to Site

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Red99

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Hi guys. I'm new to the site. I recently picked up a '99 Tahoe 2WD that has the infamous slip yoke thud when applying or letting off brakes.

I know that a lot has been said about this issue already, and some say just replace the yoke with a nickel-plated one, but to me, that shouldn't be the only fix.

It seems to me that GM evidently had a faulty design in this yoke that had too much endplay. That seems to be the real issue at hand. If it were a question of the splines wearing out (hence the recommendation to go to nickel-plated version of yoke), then the yoke would be stripping out and spinning freely if the splines were getting worn.

Since that doesn't seem to be what is happening, then it seems like what is really happening is there is a sliding motion that is happening when the driveline loads & unloads-- which explains why some of the fixes like the racquet ball one tend to work-- they take up the space that is in there, so there is effectively no endplay or 'slop' in there.

My question is this-- assuming that the issue is in fact the amount of endplay in there, then has anyone measured the exact amount that is needed to be (essentially) shimmed? If it's basically a standard length by which GM made these units too long, then an equivalent-thickness 'shim' should fix the problem.

I was thinking about using a rubber or Teflon disc in mine.

Any thoughts on my theory, or any other ideas for a fix that have actually worked long-term?

Thanks for any input!
 

SunlitComet

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the slip yoke must be able to slide freely on and off the output shaft. It is the slip yoke not being able to slide freely on the shaft which causes the issue. Get the nickel one and be done with it.
 
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Red99

Red99

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Thanks for the response, but I must be unclear on what's going on with a transmission output shaft. Does it really move back and forth as it engages the yoke? I was under the impression that it spins, but doesn't move in and out of the trans. as it engages.

That said, if the nickel-plated version really solves the problem, I guess I'll just have to get one.
 

SunlitComet

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Tranny shaft spins only. yoke is spun by tranny shaft but yoke slides on the tranny shaft as the rear diffy moves up and down during suspension travel and from torque on the axles. The clunk you get is the yoke getting stuck and not being able to slide freely and then suddenly breaking free under pressure and hearing the suspension and drivetrain shock(noise, not part) as a result. Hope that helps.
 

Justinj360

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On a side note (that I think could possibly benefit a lot of people), what would I ask for if I were to go to my dealer? I'm worried about getting that stare from the parts guy as he tries to wrap his mind around what I'm talking about. Is there a more official name for this yoke of maybe a part number or something? Thanks.
 

SunlitComet

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On a side note (that I think could possibly benefit a lot of people), what would I ask for if I were to go to my dealer? I'm worried about getting that stare from the parts guy as he tries to wrap his mind around what I'm talking about. Is there a more official name for this yoke of maybe a part number or something? Thanks.


read thread and buy from fort wayne site i listed on post 36.

http://www.tahoeyukonforum.com/forum/showthread.php?t=38275
 

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