Re: What if the lockup torque converter clutch is the cause of the main bearing problems?

Posted by Ross On 2016/10/19 20:25:36

I also suspect that many of the main bearing troubles come from the very low lockup speeds that Packard specified. I believe that was some thinking left over from the high torque at low speed engines from the thirties. Those engines had far lower unit bearing loading than the v8s. The customer base seemed to expect direct drive at low speed as suggested by the change in mid 55 to lower the direct engagement speed. The crankshafts don't like it and the trans don't much care for it either. It is not unusual to get torque agony pulling a hill at low speed in direct

On the winding hilly roads around here those low engagement speeds are purely annoying and lead to lots of lugging and then kickdowns. That is why I raise the direct engagement speed quite a lot on all the trannys that I build. My 56 Packup will go direct at 28 at light throttle. With a 3.07 rear, that is still a bit too slow in many instances and I will bump it up a bit more the next time I have the pan off.