I am just finishing up my SM465 conversion on my 60, and have run into a potential show-stopper. I finally got the 465, adapter and 4sp transfer case installed tonight and fired it up (without driveshafts) to see if all was well.

Well, all is not well: I have this low-pitched knock when I am in 4th gear... Doesn't happen in any of the other gears (Including reverse). I can't imagine what could be knocking... It sounds like its at engine rpm which makes sense as it would be the 1:1 gears.

Has anyone had this problem before? Any suggestions?

Thanks!

I know my 10-spline 465/205 has a worn coupler sleeve that makes noise during coasting and decel... it's a LOUD rattling noise.. doesn't do it under load though.

I dunno if this will help, since your setup is different than mine after the tranny.

After talking to a couple folks, it may be the fact that the 465 was unloaded... I will put the driveshafts on this Monday evening and
take it out for a before I pass judgement on my install...