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**'68OrangeSunshine** · 04-09-2023, 09:42 PM

My funny noise turned out to be the forward prop shaft disintegrating.

Thought it was out-of-balance new tires on 1.25'' wheel spacers. Changed back to old 15'' rims and 33x12.50x15 knobby tires. Wasn't it.

Checked differential with rear end lifted. Front shaft rotated, too.
OK, so the Transfer case had got shifted to 4-Hi and I ran it on the freewy unawares. Back to 2-Hi. Sounded better.
But still a nagging tink-tink in the front.

A closer look showed a lost retaining clip on the 2nd U-joint on the front shaft was working the bearing cap loose.
I got a fresh U-joint to replace it. When I got the bad U-joint off, I saw some little bearing cup inside the double-cardan had disintegrated over a period of years.
So I had to pull the front prop shaft.

Noise is gone on my now-2WD K/1500 Jimmy.

A new one will run $650 from Jegs.
The front shaft on my '67 K/10 Sub appears to be identical. When I get time off, I can cannibalize that.

04-09-2023, 09:42 PM	#12
'68OrangeSunshine Senior Member Join Date: Feb 2002 Location: Tucson, AZ USA Posts: 7,105	Re: Clunk identification My funny noise turned out to be the forward prop shaft disintegrating. Thought it was out-of-balance new tires on 1.25'' wheel spacers. Changed back to old 15'' rims and 33x12.50x15 knobby tires. Wasn't it. Checked differential with rear end lifted. Front shaft rotated, too. OK, so the Transfer case had got shifted to 4-Hi and I ran it on the freewy unawares. Back to 2-Hi. Sounded better. But still a nagging tink-tink in the front. A closer look showed a lost retaining clip on the 2nd U-joint on the front shaft was working the bearing cap loose. I got a fresh U-joint to replace it. When I got the bad U-joint off, I saw some little bearing cup inside the double-cardan had disintegrated over a period of years. So I had to pull the front prop shaft. Noise is gone on my now-2WD K/1500 Jimmy. A new one will run $650 from Jegs. The front shaft on my '67 K/10 Sub appears to be identical. When I get time off, I can cannibalize that. __________________ Every 25 years I like to rebuild that 292, whether it needs it or not.