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Atx To Mtx Swap Instructions

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Full write-up of 4cyl ATX to MTX swap

Note: I did this about a year ago (8/2007), but never posted it. After a year and over 60k miles, car is doing great.

Get parts:

You will need from salvage yard:



Shifter and Rods

Right side intermediate shaft, the bearing hanger is different (shorter) on the MTX cars

Mounts, get all of the mounts attached to the transmission, INCLUDING THE FRAME SIDE!

Brake master cylinder (you really only need the reservoir)

Clutch master cylinder

Clutch hydraulic lines

Clutch pedal assembly

Brake pedal assembly (optional)

Body Harness side of all connectors

Get all of the hardware too.

I paid $350 for all of the above including the old clutch (that I canned)

From the parts store:

Clutch Set (Clutch disc, pressure plate, throwout bearing, pilot bearing)

Left (drivers side) axle

Pint of brake fluid

3 quarts 75W-90 gear lube

Exhaust flange gasket

$207.05 for the above.

Before you put your car on jack stands, loosen the axle nuts, and break the axles free in the hubs. 626's have a tendency to have the axle stub freeze in the hub. Use your BA hammer to shock them loose. It's a lot easier to break all of this loose while the car is on the ground. If you have custom wheels you may not be able to access the nut and axle. Use your spare.

When I did this I pulled the engine too. It makes the whole job MUCH easier.

Remove hood.

Remove battery cables from battery, remove battery.

Drain radiator into a clean container, set aside. Cut rubber lines to transmission cooler, you won't be using them anyway. Unplug radiator fans. Remove radiator.

Loosen belt tensioner for power steering/airconditioner.

Remove power steering lines routed across valve cover.

Remove power steering pump. DO NOT REMOVE LINES FROM PUMP. Tie it out of the way.

Remove air conditioner compressor, tie up so it doesn't hang from hoses.

Remove airbox and MAF connector.

Unplug all electrical connectors from top of engine, this includes injectors, and all sensors. Don't worry about the alternator and starter connections, you'll get them later from underneath.

Remove heater hoses from engine.

Remove power brake vacuum line and any other vacuum lines that run between the engine and body.

Remove fuel lines from engine fuel rails. Mark them so you put them back in the right spot.

Remove throttle cable from throttle.

Put car on jack stands.

Start at the bottom and work your way up.

First drain all of the stinky, burnt fluid out of the transmission, there is a drain plug at the back of the transmission case, pull it out and let fly. Let it drain while you do the next step.

Remove wheels

Remove plastic splash shields from both sides.

Remove clip holding brake hose to strut, remove brake calipers, wire them up so they don't dangle from the hose (bad). Don't wire them to the springs.

Break loose tie rod ends. Don't bugger up the threads.

Remove sway bar end link on one side. (This makes it much easier to get spindle out)

Remove clamp bolt on lower ball joints, Break loose lower ball joints. (Don't bugger up the boot)

Remove 4 nuts holding strut to body, remove strut and spindle assembly. (This would be a great time to replace your struts and ball joints) Set the struts aside.

Put the drain plug back in the transmission. Dispose of the fluid in a responsible manner.

Remove the left/right crossmember from underneath the steering rack.

Remove the front/rear crossmember from underneath the transmission. You will remove the front and bottom motor mounts in this step.

Take a pry bar and pop the left axle loose from the transmission. Pull the axle out and set aside, you'll need it for the core charge if you bought a remanufactured left axle.

Remove the three bolts holding the right axle intermediate shaft bearing to the block.

Pry the right axle out of the transmission, remove the entire axle assembly as a unit.

Remove the through-bolt on the rear engine mount. If your car is like mine, you will have to break loose a power steering fluid line from the steering rack to get the bolt out. Dumb design.

Now the engine and trans are only supported by the end motor mounts.

Remove the starter electrical connections. Leave starter in place.

Remove the plug on the back of the alternator.

Remove the main power connection to the alternator (12mm nut). Leave alternator in place.

Remove the connector to the oil pressure sender.

The speed sensor connector is jammed underneath the rear motor mount. Wait to pull it off when you have the engine lifted up and half out.

Remove exhaust downpipe from manifold.

Attach engine hoist using factory lifting eyes, if you have a motor tilter, use it.

Take a slight strain on the engine engine with the hoist.

Remove right side motor mount nuts, remove frame side of mount completely. It WILL get in the way.

Remove transmission side motor mount from transmission.

Lower engine slightly.

Remove transmission side frame mount (four bolts)

Lift engine from car, be sure to be careful, look for any still connected cables and hoses. When you have it up far enough to unbolt the speed sensor from the rear of the trans, remove it with the connector still attached. Separate connector from sensor.

Pull engine out, set down safely.

Remove trans to engine block bolts (There is one hidden underneath the front motor mount)

Remove trans, throw downwind. (It's worth about $20.00 at the scrapyard)

Remove converter nuts through starter hole. Remove converter, don't drop on feet. Discard.

Remove flexplate from crankshaft. Discard.

If you are getting close to your scheduled replacement of the timing belt, DO IT NOW! It's a breeze with the engine out.

Same for changing the oil.

Take a break. Clean yourself up, you need to be clean for the next step.

Remove drivers seat.

Remove console. It's a bit of a trick, three screws per side, two in the storage compartment. Pull off the trim around the shifter, there are a couple there, pull off the console front and there will be four under the radio.

Remove shifter.

The ignition lock cable can be forced off its ball with a screwdriver.

The shifter cable is a bit tougher, pull the clip off of the mount to give you some slack then pop it off of the shifter.

Remove the four bolts holding the shifter to the floor.

If you will never put another automatic in the car, use a cutoff wheel or boltcutter to cut shifter cable at firewall and pull out from both ends. Seal hole in grommet with silicone. Don't worry about the ignition lock cable, just leave it alone.



Brake: This is actually the most difficult part of the whole swap. If you want to go completely factory, you will need to replace the brake pedal assembly with one from a manual trans car. This is a SERIOUS pain. I looked at it, looked at the auto brake pedal assy, then back at the manual assy, and decided to break out the jigsaw. Trim both sides of the pedal to fit the pedal rubber. Round off the corners and no one will be the wiser. Took about 5 minutes to do.

Clutch: Look under the dash, on the firewall where the clutch pedal bolts up there is a plastic plug, take a rod and an hammer and pop it a couple of times and it will come out. Put your clutch pedal in the hole and attach the clutch master cylinder to the other side. Note, There is a welded stud under the dash that attaches to the top of the pedal assembly, don't leave it out. Have fun putting the nut on the master cylinder stud that is inside of the car. What a pain.

Get back under the car.

Pull the two rubber exhaust hangers off of their metal hanger rods. Let the exhaust hang. Take your shifter and rods and put them through the shifter hole in the car. You may have to massage the heat shield to get them in. Put a couple of nuts loosely on the shifter inside the car. Do not tighten. Get back under the car and rehang the exhaust. If it gives you trouble, put some water (or spit) in the hanger holes and they should slide right back on. I wouldn't use oil or WD40, it may degrade the rubber.

Press out old pilot bearing from center of flywheel and install new bearing.

Attach flywheel to crankshaft using the bolts from donor car. Torque to 71-75 foot lbs. I use blue loctite on these.

Put clutch disc between pressure plate and flywheel. Be sure to have disc in correctly. Observe markings on disc.

If no marking, the raised spring side goes AWAY from the flywheel.

Loosely attach pressure plate, use lineup tool to center disc with pilot bearing.

Torque pressure plate to 14-19 foot lbs. I loctite these too.

Put new throwout bearing on clutch fork. Lightly grease transmission splines and tube. Put a dab of grease on fork pivot points.

Put transmission on engine. It's a lot easier with two people but it can be done by yourself if you have to. Jiggle it around a bit if everything doesn't line up at first. DON'T FORCE IT. If you do, it will probably push the inner race out of the pilot bearing and you have to take it all back apart again. The bearing is a standard bearing found at any bearing supply house, you don't have to buy it from a parts store for 3X the price.

Torque engine to trans bolts to 66-85 foot lbs.

The smaller bolts are to be torqued to 14-18 foot lbs.

Put the front engine mount on the transmission.

Remove rear engine mount on frame and replace with manual transmission mount.

Put on left side frame mount.

Lift engine and put it back in, Attach right motor mount, put left motor mount on transmission once in car, put through-bolt in mount and remove hoist. Engine is now supported on both ends.

Attach line between clutch master cylinder and clutch slave cylinder. See alternate solution before doing this step. Using a turkey baster or similar, remove fluid from brake master cylinder. Take screw holding reservoir to cylinder body out and remove reservoir. Put some rags underneath to catch any remaining fluid. Put on reservoir from donor car and attach hose to clutch master cylinder. Put some fluid in the brake cylinder. If you are lucky you won't have to bleed the brakes. Get a friend to help you bleed the clutch. It shouldn't take long, just be sure not to run the brake master cylinder dry.


My junkyard master cylinder reservoir was a POS. It was brittle and broke before I could even pull it off the master cylinder body. Reman master cylinders do not come with this reservoir, so you are stuck with buying it from the dealer. ($$$) Solution, go to a salvage yard and get a Ford Ranger clutch master cylinder remote reservoir. Mount it to the firewall and plumb it to your clutch master cylinder. Shouldn't cost you over $5.00 Advantage is that you don't have to screw with the brakes at all. Just fill it up and bleed the clutch as before. If I were to do this again, I wouldn't even buy any of the brake parts (pedal assy, master cylinder).

Reassembly is reverse of disassembly with the following exceptions.

Don't tighten the shifter in the hole until the motor in mounted on all of the mounts, and the shifter rods are attached.

Use a new gasket on the exhaust flange.

Be sure to fill transmission with oil before installing the airbox, but after the axles are installed. Before installing axles, be sure to put a dab of grease on the seals so there won't be a problem later.


Transmission range connector

B/L to Green (F) - will enable car to start

Yellow/Red to Red/Yellow - reverse lights


Y/R - R/Y


LG/B - B/Y (Ovdc)

Tie LG/B to Green (F) for start

Tie Y/R to Y/R and R/y to R/Y for reverse lights


I couldn't get the check engine light to go out, it would keep throwing codes after about 50 miles. The easiest solution was to buy a used computer from a manual trans car. I should have done it from the beginning, instead of screwing around trying to trick the ATX computer. Plugged right up, cleared all codes, passed emissions. Paid 60 bucks for the new computer.



2001 LX

bunch of other stuff

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Wonderful! :biggrin: I want to do this to a 626 someday. I see so many atx for sale that have bad atxs. Quick question, do you have any pictures? This is invaluable. Thanks for posting!

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I could have really used this a few months ago!! I say sticky.

I dig the Ranger Brake Reservoir swap. I just switched out the whole unit, booster and all, as to not break the reservoir.

On my '97 I4, the MAFs are different pinouts, and the coil is external on the ATX, and internal on the MTX, so if you switch computers on the 93-97, you need to switch the harness and MAF too. Don't forget the switches for the brake and clutch as well.

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yeah thanks man i did the swap myself and i have pics of everything i just got 2 figure out how to post em all it says the file size is to large or maybe thats what she said lol img-312874-1-laugh.gif

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Use photobucket.com for your image uploading. It's free all you have to do is register an account and use bbcode. They even provide you the bbcode for each image. It's what I use for all of my images. Easy and works great but their site can be really slow sometimes but who cares it's free.

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You can get an after market tach and use the directions to hook it and test to see if it works, if it does then return the tach. If not keep and use it till you figure out the issue.

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everything works except for the speedometer

You can get an after market tach and use the directions to hook it and test to see if it works, if it does then return the tach. If not keep and use it till you figure out the issue.

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oh dur, sorry didn't read it correctly.

Your year has a speed sensor built into the ABS. It's different between auto and manual. I think that might be the issue. :)

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What car did you pull the the transmission from? I have the same year/model and want to do this but Im unsure what car would have a mtx that would easily fit

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Do you think these same parts will be needed for the 97 lx model? I'm not putting in another automatic car is at the shop right now. I don't have the brains nor tools to pull this off myself lol. But luckily I have a performance auto shop in town

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Sounds like electronics wise, wiring harness, MAF, ECU, speed sensor and perhaps the TB are different from ATX to MTX?  I've read that the TPS is different as well so its easier to just swap entire TB's between the ATX and MTX car.


I am very interested in this swap as my 16y/o son just bought a '96 with 170k that runs great and has cold a/c looks good, quite clean but reverse just died.  Luckily he only paid $250 for it and I have a shop and lift and am thinking about making a more permanent solution to the weak transmissions in these cars.

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