Ive been trying to track down a ringing noise in 4th gear @ 2000rpm. The sound is comming from the shifter area. I checked the rear end, no play in the pinion, the oil looks great no metal on the magnet. I checked the transfer case, a little play so I replced the seal with a Marlin seal and re-torqued the nut. The oil looks good. I found some metal flakes like the hardening on the bearings was comming of in the transmission oil. I completely rebuilt the transmission. The rear u-joints are all tight no play at all. I thought maybe my exhaust was setting up harmonics, so I put a c-clamp on the exhaust at different places and nothing. Ive got a header and a fully welded exhaust with a flex joint before the cat. Ive run out of ideas and am thinking maybe just run it till something gives. I also put in a v6 transfer case mount. The truck has 30,000 on a rebuild and 225,000 total miles. Im running 4.88 gears with a truetrac in the rear. The only thing that has not been rebuilt is the transfer case, but it works great and the oil looks like honey. I know u-joints are cheap so I guess thats next. Maybe the stiffer transfer case mount is the culprit. Anybody feel free to chime in with suggestions. Thanks in advance for any ideas, and before I forget its a 89 22rec shortbed.

 

Nodody

 

Possible that it is harmonics somewhere else other than the exhaust. Does putting the clutch in make it go away, is it speed relate?

 

No, engaging the clutch or disengaging it makes no difference, and its not really speed related. It is in 4th gear only @ 2000rpm to 2500rpm. It is really strange, I feel like Im chasing my tail. Thaanks for the input.