Post by aurorabrain on Oct 1, 2008 13:51:48 GMT -6
Due to the increased PM's about installing a Cadillac transmission into your Classic (1995-1999) Aurora I've decided to make some general information statements about them.
All of this information is for 1995-1999 4T80-E Transmissions.
1. A 3.11 gear ratio transmission is ok as long as you can use your original torque converter and differential. When swapping the differential there is a spacer (washer) and thrust bearing on the end of the differential. The spacer is there for final assembly end play adjustment (5 different thickness ranges) and should stay with the transmission it came out of, not to be swapped out with the differential.
2. The wiring harness pinout is identical across these model years, but the internal harness of a '95 will not fit into later transmissions (into the case) due to the seal at the case where the harness comes out of the transmission. This is not an issue unless you are changing out the harness for some reason.
3. The shift cable bracket, and the shift lever (external bolted to transmission) need to stay with your Aurora, the Cadillac ones are different, and they are also different in Auroras (usage is from 95-96 same to 97-99 same). 1995 Park/Neutral safety switches are unique to an Aurora also and needs to stay with the vehicle (put it on your replacement transmission) if it's a 1995 car.
4. Replace the filter in the side cover. This should be done whenever you have the transmission or engine out, it doesn't make it much past 100k miles before starting to plug up with clutch material. If you get a hydraulic whine on a cold start in the winter you should change this filter immediately. I've seen more than 5 transmissions fail after seeing this warning sign.
Finally, if you are having problems doing this swap and you need to ask me a question i have no problem answering PM's but i do get very busy from time to time and it may be a couple days. I respond faster to e-mail because it goes to my cell phone. Anything that anyone would like to add to this post please feel free to do so.
All of this information is for 1995-1999 4T80-E Transmissions.
1. A 3.11 gear ratio transmission is ok as long as you can use your original torque converter and differential. When swapping the differential there is a spacer (washer) and thrust bearing on the end of the differential. The spacer is there for final assembly end play adjustment (5 different thickness ranges) and should stay with the transmission it came out of, not to be swapped out with the differential.
2. The wiring harness pinout is identical across these model years, but the internal harness of a '95 will not fit into later transmissions (into the case) due to the seal at the case where the harness comes out of the transmission. This is not an issue unless you are changing out the harness for some reason.
3. The shift cable bracket, and the shift lever (external bolted to transmission) need to stay with your Aurora, the Cadillac ones are different, and they are also different in Auroras (usage is from 95-96 same to 97-99 same). 1995 Park/Neutral safety switches are unique to an Aurora also and needs to stay with the vehicle (put it on your replacement transmission) if it's a 1995 car.
4. Replace the filter in the side cover. This should be done whenever you have the transmission or engine out, it doesn't make it much past 100k miles before starting to plug up with clutch material. If you get a hydraulic whine on a cold start in the winter you should change this filter immediately. I've seen more than 5 transmissions fail after seeing this warning sign.
Finally, if you are having problems doing this swap and you need to ask me a question i have no problem answering PM's but i do get very busy from time to time and it may be a couple days. I respond faster to e-mail because it goes to my cell phone. Anything that anyone would like to add to this post please feel free to do so.
