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Further "clunk" Diagnosis

zedbear

By zedbear
in Ask A GM Technician

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zedbear Enthusiast

zedbear

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(Truck info in sig)

 

Ok, so the dealer told me last month the hard 2-3, 3-2 shifts, and reverse clunk is due to excessive lash in the t-case. However, I've been thinking about this and wonder:

 

Why wouldn't it do this during ALL gear changes, such as when putting it into drive and when shifting 1-2 and 3-4, for example, and not just 2-3. 3-2, and putting into reverse?? It engages into drive perfect and the other shifts feel fine.

 

Someone mentioned in another thread it could be the transmission itself. I think they said the "sun gear". It almost seems like its shifting to 3rd too quickly. it just feels wierd. I saw the TSB regarding some clunks being "normal" but this clunking goes beyond that I think.....

 

Sometimes it also seems like it "falls out of gear" or slips momentarily between 2 and 3, mostly when in traffic. Its only done this a few times that I've noticed but I am wondering if all this is related somehow....

 

Any thoughts?? :lol:

zedbear Enthusiast

zedbear

Posted
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Anyone??....

 

 

Clunk issues aside, it FINALLY snowed enough the other day to verify 4x4 is working. Goes like a bat out of hell from a stop in either AUTO or 4 HI in the snow but it makes a god awfull grinding/rumbling noise, when on the gas especially. Still making rubbing noises when turning in AUTO, even in the snow. But it DOES work at least. I think the sound is coming from the front but it could be from under the truck as well (t-case). Clunking and other sounds may be related or they may be two totally different issues.

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