A604 tp A543 Transmission Swap
A bit of Introduction
I did quite a bit of internet research before finally deciding to attempt swapping the old A604 A/T for a A543 M/T. The Queen had an annoying shudder at about 40 MPH that I discovered was common to the computer controlled lockup torque converter. Something about the TC clutch slipping. I am certainly not a transmission mechanic, but I figured that just replacing the TC would only be a temporary fix.
The A604 was rebuilt at about 95K miles. It went into "limp mode" one afternoon, and stopped giving my wife any forward gears before she could even get the car back to the house!
When the A604 started acting up again at 130K, I decided that I'd had enough crap out of the thing, and my search for 5 speed bliss took off.
Prowling my favorite boneyards produced nothing but frustration (well, it did give me the idea to replace the Queen's interior).
A chance phone call to a yard in Erie, CO led me to West Side Auto in Ft. Morgan, CO. Not only did they have the coveted A543 tranny, but a very unexpected and welcome bonus.
A mostly complete 1993 Dodge Daytona! Since the LeBaron and Daytone share common mechanicals, I had accidently uncovered a gold mine of useful parts.
After two 145 mile round trips in my truck, I had everything (and I mean everything) necessary to do the swap. A timely offer by a close friend to use some open space in the shop of her family business, and it was time to do the dirty deed.
The Pedal Swap
I read that it is possible to just pull the pivot shaft out of the existing brake pedal mount, and put the new brake and clutch pedals right in. Then I read a few horror stories of what can happen if the springs get out of the self adjusting clutch! Also, it was nice being able to use the existing brake switch, and after discovering that the clutch safety switch is simply jumpered in an A/T car, the clutch switch was also a simple plug in. (no bracket fab required, which is good since I can't fabricate to save my life!)
After removing the trim, kick panels, and instrument cluster.
Steering column dropped to get access to all those damn bolts and nuts.
Old brake pedal mount removed. While I was in there, I removed the cable from the A/T shifter that prevents you from removing your key unless the tranny is in park. Wasn't going to need that thing anymore!
The new pedal assembly in place. I'm not a small guy, so getting some of those fasteners back on was quite annoying.
The Tranny Swap
The Queen up on jackstands. After the wheels, we pulled the ball joints out of the steering knuckles, and then removed the halfshafts (messy!) After the tranny drained for about an hour, it was time to get serious.
Say goodby to the A604. I won't miss it.
One last look to remember it by. Since I decided right off that I wasn't going to hack up my wiring harnesses, all the old sensors on the tranny went with the rest of the trash.
When I said I had everything, I wasn't kidding. I took the K Frame from the Daytona (I did mention that I wasn't good at fab!). We dropped the K Frame as soon as the A604 was gone. It was much easier to reach the steering rack bolts that way.
New K Frame in the car. Shifter cables caused quite a headache (literally, as I managed to get a nice migrane going during all of this!). Apparently the Daytona routes them a bit differently, and in order to get them to clear the exhaust manifold, and not look like a pretzel, I had to trim 6 or so inches off of the insulation wrapped around the cable so I could pull more into the cabin of the car. Having read about the sloppy feel that the stock shifter bushings can give, I had a set of Polybushings plastic bushings in my hands before starting. Very nice. Made the cable install more difficult, but it was worth it in the end.
Flywheel! I went with a stock aftermarket clutch, mostly because I was running low on cash, and like to have a little money in the bank. I can always change later (maybe after I have the tranny rebuilt:D).
The A543 installed. I have not included any photos of me swearing at the tranny for the better part of an hour while trying to get the input shaft to line up with the clutch. We were stupid and used a large floor jack. The tranny thought it would be fun to slide off of the jack every five seconds or so.
After managing to get the tranny on, and with the top 4 bellhousing bolts in, we jacked up the tranny to install the upper tranny mount, and discovered that the A/T bracket won't work with the A543! Never fear, I said everything didn't I. West Side had included all of the mounts and brackets from the Daytona, so a quick swap of the bracket, and the mount came together perfectly.
The front mount and starter were next, and then the bobble strut. Since I swapped the whole K Frame, everything lined right up.
The A/T shifter went next, and with it the cable we had pulled into the cab.
The manual shifter bolted right up. We attached both shifter cables without much trouble. Nice firm feel to the shifter.
My faithful assistant (and wife of 18 years) re-installing the control arms to the ball joints. After that, the brakes went back on. We left the nuts off the ends of the halfshafts so we could center the engine after the wheels were back on the ground.
1 1/8 inches of travel inward on both halfshafts. No adjustment required. The halfshafts were also from the Daytona. They were in great shape, and I knew they would fit. We installed the nuts, and torqued to 170 foot pounds.
That pretty much wrapped up the tranny swap.
From 1993 Daytona Donor Car
A543 5 Speed Transmission
Shifter and Cables
Brake/Clutch pedal assembly
K Frame, including control arms and bushings
PCM (Engine Computer)
Manual Transmission Wiring harness
Dust plate to cover the bottom of the flywheel
Upper transmission mount bracket
I swapped PCM's but it is possible to run with an A/T computer in a car with a M/T. The Daytona's PCM will help the engine idle correctly without the heavier A604 in the car.
By using the M/T harness, I was able to completely remove the TCM and it's harness from the car. We were a little nervous before starting her up the first time, but she fired on the first crank.
It took us the better part of 3 days to do all of this work. We started on a Friday afternoon, and finished Sunday evening. I probobly spent too much at the boneyards, but it was nice knowing that I wouldn't need some esoteric part at 11PM on a Saturday night!
I had read statements from several folks who had done this swap themselves that it was like getting a whole new car. I was not disappointed. I have had 9 Ford vehicles in my life, and only this Mopar. Among my Fords, I have had a 1988 Thunderbird Turbo Coupe, and a 1989 Probe GT. I still miss my turbo Fords, but this little V6 Mopar is a very fun ride, especially with a 5 speed.
Maybe a turbo V6?
I will show/talk your ears off about the interior work we did on the next page (I'm still waiting for one piece before I post pictures). Included will be how we used some of the Daytona's interior (mostly console and shifter boot) as well as some relics from the boneyard. Stick around!