Georgia trans rebuild
I had the privilege of working on a local Georgia Crown Vic recently, A very clean 2002 black LX sport with 82K on the odometer. The owner of the car says he found the transmission dipstick not seated in the filler tube (raised about 2") about 4-5 months ago and after that the transmission started shuttering, then eventually stopped going in any forward gear. Fortunately, he stopped driving the car and trailered it to me. The transmission came out of the car with out incident, other than 3 of the 4 exhaust flange bolts breaking.
Once I got the transmission apart, I found the intermediate and direct clutches were delaminating, the forward clutches were burned and the OD band was burned and starting to pit.
The friction material peeled off the clutch discs like wet paper, I have never seen anything like it.
Intermediate clutch
Clutch Delamination - AKA wet paper
Direct clutches
OD Band
there was some evidence of water in the fluid and the case, most of the water I found was in the pan and the extension housing.
I also found evidence the output speed sensor had contacted the ring gear on the output shaft, damaging the sensor.
The direct clutch piston showed some signs wear on the inner face where the seal rides, there was also some machine markings that did not polish out, I replaced the piston with a good used piston.
The valve body was completely disassembled and cleaned. The seperator plate also showed signs of water intrusion (mild rust build up). I cleaned and drilled the seperator plate according to Jerry's specifications (Jmod) and installed updated Sonnax shift valves.
The stock pressure regulator valve showed moderate wear.
Knowing that owner of this car will soon be doing the MZT and having Lonnie tune the car, I chose to drill the #2 hole (controls 1-2 shift) in the separator plate with a #39 drill bit (measures .0995") and install the Lt blue upper and Purple lower 1-2 accumulator springs. The rest of the holes in the separator plate, I drilled with a 7/64" drill (.1094") The shift is more responsive now, but not harsh. Personally, I think it could be more crisp, but it should improve once the tune from BOC is installed.
I did some lubrication modifications while putting it back together. The Stator has 3 feed holes for the Intermediate one way roller clutch, Intermediate clutch and reverse clutch. those 3 holes were enlarged to 3/32" or .093". I also made the feed holes on the direct drum snout larger, these holes were increased to 1/16". Enlarging these holes improves lubrication to the sun gear and related bushings, which have a high failure rate under heavy use.
Going back together, the transmission got new rubber seals and gaskets, new high energy direct and intermediate clutches, new forward clutches, new reverse clutches and new OD band. I removed the wave plate in the forward clutch and increased it to 6 clutches. This will improve the torque capacity of the transmission. I also installed a spiral snap ring on the mechanical diode intermediate one way clutch. The intermediate one way clutch and the reverse drum see very high RPM in 3rd gear and the OEM snap ring is notorious for getting flung off at this high RPM. The new spiral ring has an outer retainer that you crimp or stake when its assembled, so the spiral ring isn't going anywhere, even at high RPM.
Everything assembled correctly, the end clearance was with in specifications and all the clutches passed an air test, with the Air test plate installed.
The transmission installed with out any serious problems. I filled it with 14 qts of Mercon V and went for a test drive. All 4 gears engaged properly but I immediately noticed there was no lock up. 10 miles later the CEL light came on and OD Light started flashing, a quick scan of the codes revealed codes p0741, p1740 and p1744, which confirmed the TCC solenoid wasn't working. I let the car cool for an hour, dropped the pan and swapped the TCC solenoid with a spare, refilled with fluid and test drove again, confirming Lock up was working.
I delivered the car to the owner on Tuesday. He is currently working with Lonnie to get the car tuned, then he will installing a Marauder air box assembly, Zip tube and 75mm throttle body.
Once I got the transmission apart, I found the intermediate and direct clutches were delaminating, the forward clutches were burned and the OD band was burned and starting to pit.
The friction material peeled off the clutch discs like wet paper, I have never seen anything like it.
Intermediate clutch
Clutch Delamination - AKA wet paper
Direct clutches
OD Band
there was some evidence of water in the fluid and the case, most of the water I found was in the pan and the extension housing.
I also found evidence the output speed sensor had contacted the ring gear on the output shaft, damaging the sensor.
The direct clutch piston showed some signs wear on the inner face where the seal rides, there was also some machine markings that did not polish out, I replaced the piston with a good used piston.
The valve body was completely disassembled and cleaned. The seperator plate also showed signs of water intrusion (mild rust build up). I cleaned and drilled the seperator plate according to Jerry's specifications (Jmod) and installed updated Sonnax shift valves.
The stock pressure regulator valve showed moderate wear.
Knowing that owner of this car will soon be doing the MZT and having Lonnie tune the car, I chose to drill the #2 hole (controls 1-2 shift) in the separator plate with a #39 drill bit (measures .0995") and install the Lt blue upper and Purple lower 1-2 accumulator springs. The rest of the holes in the separator plate, I drilled with a 7/64" drill (.1094") The shift is more responsive now, but not harsh. Personally, I think it could be more crisp, but it should improve once the tune from BOC is installed.
I did some lubrication modifications while putting it back together. The Stator has 3 feed holes for the Intermediate one way roller clutch, Intermediate clutch and reverse clutch. those 3 holes were enlarged to 3/32" or .093". I also made the feed holes on the direct drum snout larger, these holes were increased to 1/16". Enlarging these holes improves lubrication to the sun gear and related bushings, which have a high failure rate under heavy use.
Going back together, the transmission got new rubber seals and gaskets, new high energy direct and intermediate clutches, new forward clutches, new reverse clutches and new OD band. I removed the wave plate in the forward clutch and increased it to 6 clutches. This will improve the torque capacity of the transmission. I also installed a spiral snap ring on the mechanical diode intermediate one way clutch. The intermediate one way clutch and the reverse drum see very high RPM in 3rd gear and the OEM snap ring is notorious for getting flung off at this high RPM. The new spiral ring has an outer retainer that you crimp or stake when its assembled, so the spiral ring isn't going anywhere, even at high RPM.
Everything assembled correctly, the end clearance was with in specifications and all the clutches passed an air test, with the Air test plate installed.
The transmission installed with out any serious problems. I filled it with 14 qts of Mercon V and went for a test drive. All 4 gears engaged properly but I immediately noticed there was no lock up. 10 miles later the CEL light came on and OD Light started flashing, a quick scan of the codes revealed codes p0741, p1740 and p1744, which confirmed the TCC solenoid wasn't working. I let the car cool for an hour, dropped the pan and swapped the TCC solenoid with a spare, refilled with fluid and test drove again, confirming Lock up was working.
I delivered the car to the owner on Tuesday. He is currently working with Lonnie to get the car tuned, then he will installing a Marauder air box assembly, Zip tube and 75mm throttle body.
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