The Stovebolt Site Forums The Parking Lot Big Bolts Aux Trans anyone recognized this??? ID-ed Aux Trans

Was vaguely aware of the possible U-Joint problem.

AS yet no final decision has been made about whether or not to use a enclosed drive-line u-joint/trunnion or a straight spline coupler.

Will not be using a U-joint with needle bearings in any case that was the first thing out the door.

Found spline couplings a W.W. Granger 1-3/8" 10 spline by 3 inches long $89.00 ugh.

The spline on the output shaft of the SM420 is also 1-3/8" 10 spline...but the splines are not cut square, the sides of the splines are at an angle.

Also if we do not use a enclosed drive-line yoke the the coupling will be floating...no way to bolt it on to output shaft of the SM420 to stop it from floating. Sure wish I could find an old GM manual. that covered these things.

All your info is of great help...please keep it coming.

Also I actually took out my measuring tape today and measured the location of the Aux Box shift lever in relation too the Main Box shift lever. Exactly (almost) 12 inches to the rear and to the left 6 inches. The hole for the shifter will be in the trans floor plate...just need my trusty hole saw.