The little tranny that could...
This tranny has served me well over the years, including putting up with abuse it takes to make a Mark VIII run a 13.4 second ET in the quarter mile. Well the time for all good things must come to an end, and this way it is under my terms. I spent part of the weekend with the car at a shop getting the tranny replaced.
I went with a race-prepped tranny built for whatever I may decide to throw at it in the future.
It started with a late model case and J-modded valve body with all the 'good stuff' inside including the rear bushing lube mod and the extra large capacity cast aluminum pan.
The 3800 stall converter remains and I included a SpeedCal device to be able to accurately program the speedo for the 4.30 gears.
Nothing comes with this car without pain however. After a late arrival, and another customer in front of me it was nearly 2 AM when we were done and we decided to put the new hard lines for the cooler off 'til another day.
The speedcal was a PITA to install. Built for mustangs, the wiring was short and had to be spliced longer since the only logical installation for the black box was in the console. With the 18 tooth speedo gear we calculated the settings for the tranny output shaft, gears and tires only to find them off by about 9%. I've since changed it and now have it within 3-4% by GPS. Another round of calculations should put that near spot on for the gears and tires I currently have.
The 4 hour plus drive home in the wee hours also showed the converter isn't locking up, so I've got some troubleshooting to do there. At first it wasn't so apparent, but once I started in the hills towards home it became quite obvious. Even still, 190* was the warmest the tranny temp gauge ever registered in the hilly terrain.
The harness needed re-pinned for the new setup, so if I'm lucky it may just be a loose pin in the bulkhead connector? Worse case I was assured would be a defective 'new' TCC solenoid. Wouldn't be the first I suppose.
I may break out my recently acquired 'break-out' box and see what it tells me.
All in all though, I'm pleased and I'm sure once I get the lock-up working, it will be a good choice to have made. The old tranny showed some unusual findings in the autopsy, but no readily apparent serious malfunctions. The pan and fluid was spotless and some of the old '93 era internal parts were almost instant Smithsonian conversation pieces. Not bad for 138,000 miles and hundreds of track passes - considering this was supposedly the worst of the 4R70W trannies ever. Just goes to show what proper maintenance can do.
