Re: Twin Ultramatic Shifting

Posted by Owen_Dyneto On 2008/5/23 8:35:22

HH56 is right on target, a combination of a steady diet of "D" driving (more or less the equivalent of starting in "L" and manually shifting to "H" on the older Ultramatics), the higher torque of the V8, and a heavy foot is what lead to the less-than-sterling reputation of the Twin Ultramatic in the first place and is just about guaranteed to lead to continued rebuilds.

I almost never use the "D" position in my 56 Caribbean and try to always ease up on the accelerator as it approaches the shift point. I don't know the prior history of the transmission but it has 89,000 miles on it (probably had a rebuild somewhere in its past) and performs well with no problems. At one time I used Dexron/Mercon but abandoned it years ago in favor of Type F which is closer in formulation to the original Type A. The changeover from Dexron to Type F eliminated the occasional clutch groan which has not reappeared since then.