Direct Springs:
We are always asked as to the correct placement and quantity of the direct springs in the 4+3 overdrive. The factory setting used a load of 1250 lbs. This load was achieved by removing or adding springs. The problem was that sometimes you will have an odd amount which leads to uneven loading of the piston. Doug Nash also did not make it a point to evenly space springs, which of course resulted in more uneven pressure. If you look at the below image you will see how we like to place the springs. We evenly space them around the threaded access plugs. We remove the center spring where the "X" is.

spring image

That means we have 18 outer and 15 inner springs. We found that this method gives good holding power as well as even load on the piston and bearings. An important point overlooked by most rebuilders is that when the overdrive slips and burns up, the heat generated usually collapses the springs and yields a weaker pressure. We stock new springs.

GM Outer Spring No. Is: 14081182
GM Inner Spring No. Is: 14081183

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