Dave - aside from the leak you have at the diff., have you changed the fluid lately and put in some new posi additive ??
Earlier this year I had so many noises in my '73, I thought I had to change out everything from the door handles back. Bearings, clutches, gears, bushings, you name it. The car not only had the tight turn crunchies, it squeaked and had some funny noises going in a straight line and even over bumps.
Before opening that expensive can of worms, I ran the car up to temp and sucked out as much fluid as I could, then replaced it with two bottles of GM posi additive and topped it off with new 90w. That was followed up by a dozen figure eights in a nearby parking lot, a 10 mile drive on the highway and another dozen figure eights and it has been quiet as a mouse ever since. I was amazed and I can't believe I'm even tempting fate by typing this.
Might be worth a try.
And +1 on not going over the 3:55's. That's what I have with a close ratio 4 speed. Lots of RPM's going down the highway @ 65 MPH. Maintaining 70 for any length of time pushes my comfort level a bit with a 43 year old SB.
|UPDATED|10/29/2015 11:21:29 AM (AZT)|/UPDATED|
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John Sigmund
valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member
Duct tape is the new Black !!