transmission shifting issue

[jhettel]

Just rebuild my three speed transmission in my 1997 Caravan. It was a real task but went pretty well. The car runs fine but it does not shift into third gear until about 50 mph. That is a bit late. It is probably an adjustment in the control valve assembly as everything else was fine. Any ideas on how to bring the 2-3 shift back down to where it should be. Also, there is a slight shudder in reverse, could this be the band to tight. I torqued and backed off to the specs called for in the rebuild manual. I did drive the van 80 miles today so the transmission is fine, just shifts at the wrong time.

[chad millett]

If you rebuilt your own transmission than you are more informed than most. I couldn't answer your question but im sure the info is somewhere here on the net.
How much knowledge is needed to do this yourself. Are there a a lot of specialty tools needed? Can an average mechanic do this by simply following the instructions provided?

[jhettel]

I think that any knowledgeable mechanic could rebuild a transmission if they had the time and tools.

First off I used Alldata which was fine but they had no torque values. I emailed them for torque values for the transmission and they sent me to their torque value chart which had torque values for the fluid pan and one other value. I then emailed them again and was told that they had no other torque values available. How can they give detailed instructions on repair procedures and then neglect to include torque values. This is a serious issue with Alldata and I am not sure I will renew with them because of it.

After I had finished the transmission I decided to get a shift kit for better shifting. I was directed to a transmission supply house in St. Louis and there purchased the rebuild booklet for the transmission. Before attempting to rebuild a transmission get the proper book online or at a transmission supply house. Hayned and the other booklets do not include transmission repair as they once did.

Special tools can be gotten around somewhat. You will need two types of snap ring tools. One that opens the snap ring for removal, and one that closes the snap ring for removal. These you will definitely need. I used c clamps for spring compressors on the pistons. You will also need feeler gauges and a torque wrench, and more than likely an inch pound torque wrench. I bought my inch pound torque wrench at Harbor Freight for $20. Snap ring pliars were on sale for $1.99.

My book called for trans gel for the gaskets and seals. I used petroleum jelly which was in such a small amound that I don't see what its use could hurt. Some of the seals on the pistons are a bit tricky. I also took pictures of the teardown for later reference, and to answer any questions at a later date.

I took pictures of the control valve disassembly. Took pictures of all the springs and where they were located. I made a big error here because when I went to assemble the control valve I could not tell the springs apart by the pictures and got four mixed up. I finally went to a junk yard, pulled a control valve assembly and sorted them out that way.

Weather did not comply with my needs. Rain and cold weather prolonged the removal and installation of the transmission to four days each way. That was due in part because I worked under the car and lighting was terrible.

If you are knowledgeable in mechanice the procedure is really pretty simple, but you must have the book for reference and torque values.

[KManiac]

Delayed upshift on the 3-speed is a throttle pressure issue. You should have a rod or a cable between the throttle body and the transmission. As you open the throttle, the throttle valve on the transmission is suppose to move with it, causing a variation in line pressure with the position of the throttle. This is why upshifts are delayed with "wide open throttle" and immediate with your foot off the gas.

When the throttle valve rod/cable is too tight, the transmission senses a wider open throttle and delays upshifts. When it is too loose, it senses a closed throttle and upshift quickly. Check and adjust of your throttle valve rod/cable to correct this issue.