Talk:Ultradrive

Latest comment: 7 years ago by PolychromePlatypus in topic Autostick
Personal observation: limp home feature edit

The transmission failed on our 1990 Plymouth Grand Voyager (10 years old with 95000 miles on the clock). The engine would spin free at some point during acceleration when the transmission changed up. The transmission would lock down to 2nd gear. We travelled the 100 miles back to our accommodation then, ss it was to cost about $2500 to fix in Frisco, CO (and an extra weeks accommodation) we drove the 1000 miles to Irvine CA... in 2nd! It cost $1000 to overhaul in Santa Ana. There were shattered components in the transmission case.

The point? - The limp home feature meant our family of six was not marooned at the base of the Rockies that afternoon, and we were able to get all of us and our baggage to Irvine to start an undergraduate exchange. Not the intended use of the Limp-back feature, but it worked!

ACB - NZ

Problems edit

The most common problem until 2001 was in the final drive section referred to in Chrysler manuals as the transfer case. A pin in the differential loosens and works out of the rotating shaft. This brings it into contact with the transmission's case causing it to cut a furrow into the case and fill the transmission pan and filters with aluminum shavings. Eventually the pin is completely out, and the differential ceases to transmit power. Typical repair includes the pin itself and replacing the transmission case and torque converter and flushing the cooler(2). The final drive differential ring and spider gears and bearings are frequently damaged. A retainer for the pin was available in the aftermarket became standard production in 2001 and made available through the factory to retrofit transmissions that had not experienced a failure and is ordinarily added to earlier transmissions when opened for service other than routine fluid refill.[1]the following patent application would seem to be untimely[2]

References

  1. ^ "Caravan differential pin leaving home".
  2. ^ "Automatic Transmission Device US 20160069448 A1".

Autostick edit

 The autostick section is specific to the floor mounted gear selector on the 1993 model year vehicles, and doesn't correctly describe TCU RPM limits, a forced shift to 1st gear after stopping after which the driver may select a higher gear to launch in (i.e. begin forward motion), that selecting the 4th (overdrive) gear resumes automatic gear selection until another gear is selected, and that when a gear is selected by autostick the transmission torque converter is locked until another gear is selected.  — Preceding unsigned comment added by PolychromePlatypus (talkcontribs) 18:10, 17 February 2017 (UTC)Reply