Join Date: Jul 2002
Location: Albuquerque, NM
From the thesis
Main Transmission Connector
Beginning with the 1998 model year, a different pin arrangement was used in the main connector on the transmission (the one at the passenger side rear). Even though the connector is the same, and you can plug them in, you cannot put a 1998 and beyond transmission in a 1997 and prior vehicle (or vice versa) without re-arranging all the pins in the connector, the transmission will NOT shift.
Manual Lever Position Sensor (M.L.P.S.)
There also was a change to the sensor on the driver’s side of the transmission that senses where you have put the gear selector. All 1997 and beyond Mark 8’s and all 4R70W’s starting in 1998 went to a totally different sensor. They do not interchange. You must keep the sensor that your car came with if you are thinking of swapping in a newer transmission.
Intermediate One Way Clutch Symptom?
No 1-2 shift or no 3rd and 4th gear. A failing one way clutch will cause a late 1-2 shift that finishes with a big bang, or will allow the engine to run into the rev limiter at WOT.
All AODE and 4R70W’s built before 1998 model year. (Some of the later years, like 1996 and 1997 were better, but not bullet proof).
This design one-way clutch is not suited for this environment.
Install the mechanical diode one-way clutch. This part is almost bullet proof.
As far as friction material goes in the direct clutch, you want to stick with the production material that was introduced in the 1998 model year. This is a higher energy material that can withstand a lot of power and torque. Also, when this material was introduced in production, the steel separator plates in the clutch were made thicker, .067” to .077”. A thicker steel plate will provide more heat sink than a thinner plate. You may be better off just buying a new direct clutch assembly that is already assembled.
This is the little shaft that connects the forward clutch cylinder to the direct clutch cylinder. There have been two different stub shafts made in production. You want to use the current shaft; this went into production starting in 1998. Looking at the groove where the splines on the small end, end, you can identify this shaft. The early shafts used a groove cut in at the end of the splines; the current shafts have a taper rather than a groove. The shaft with the taper is much stronger than the shaft with the groove, the shaft with the groove tends to break at the groove.
I think there is enough here to tell you that unless you fixed your Bird trans with these things, don't do it.