Re: Rockwell t221 gear slop
 

Same here. Couldn't find the rubber replacements and ended up with the urethanes.

Yep. Motor and transmission mounts too. Its a trade off. Strength vs better isolation.

Re: Rockwell t221 gear slop
 

Reviving this old thread, I had my 1962 T221 cover off today when I pulled it to repaint it. I rebuilt it about 1979 or 1980. The gears on the idler shaft on my transfer case are solid and have no movement on the idler shaft. I've never noticed my transfer case to whine or make any noise. I've owned my 1962 GMC K1000 Suburban since 1978.

Re: Rockwell t221 gear slop
 

I sold that truck about 3 years ago, but I do stay in touch with the guy that bought it. He made a gasket for the rear output (it was still leaking after i put it back together) and hasnt touched it since nor has he had any trouble with it.

Re: Rockwell t221 gear slop
 

Pondering what controls the end play of the gears and spacer on the idler shaft, it is probably the bearing cones on each end. The stack height of the two gears plus the spacer is probably the same as bearing shoulder to bearing shoulder on the shaft. Maybe the shaft shoulders are a few thousands shorter than the stack height of the gears and spacer to put them in compression. If the bearing cones do compress the gears, it would be good to shim the spacer to ensure compression.

Hazy recollections from rebuilding my T221 over 40 years ago, but I don't remember if gears on idler shaft were a tight fit on splines or not. May have had to drive or press shaft into the gears during assembly. A tight fit on the shaft was probably built into the manufacturing, and no play of gears on shaft intended. It may have been a more durable unit if both gears and spacer were manufactured as an assembly.