G-series 5sp Transmission: Complete Teardown & Rebuild w/LSD & 5th Gear Swap

bullshark524

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2000 mazda protege es soon to be 2000 mazda protege klze
let me just start by stating that this is not my thread i got it from imazda but since you need to registar to see it i am posting it here
G-series 5sp Transmission: Complete Teardown & Rebuild w/LSD & 5th Gear Swap
Photos by: Intruder, Mazdaracer, SgtRauksauff
Special Thanks go out to Intruder and CleanAWD for their invaluable help!! and to SgtRauksauff for his photos, that we used to disassemble the transmission and make this tutorial!



This How-To will guide through a complete transmission teardown and rebuild using a 1995 Ford Probe GT G-Series transmission, an MX6/626 5th Gear and an OEM [MSP] Mazdaspeed Protg LSD. This is not a how-to on rebuilding a broken transmission, this how-to assumes you have a good working transmission to start with.

This LSD will fit all G-series transmissions (MX3, MX6, 626, Probe GT, Protg/MP3/MSP/P5, EGT, ZX2) the differential spline count is 28.

FSM style PDF file for teardown and rebuild, with more indepth info on *rebuilding* the trans. Thanks to Focus for the link.
http://www.mazdaspd.com/resources/Transmission_Rebuild.pdf

and incase that link ever disappears, this is a permanent link on the iMazda server
http://www.imazda.com/mazdaracer/V6/LSD/Transmission_Rebuild.pdf


Contents
Segment #1: Teardown
Segment #2: LSD and 5th Gear Parts
Segment #3: Rebuild
Segment #4: Notes and Tips
Segment #5: Tools/Materials Needed




Segment #1: Teardown


Once you have your transmission removed from the car and on your bench, we can begin. [BE SURE TO DRAIN ALL THE FLUID BEFOREHAND] Have a good size area to work with and lay out plastic bags, cardboard and/or shop towels for laying out the parts and for any fluid spills. Also a good idea of to have extra shop towels handy. It also pays to be able to walk on both sides of the workbench, saves from moving the transmission around.

NOTE: If you have left the slave cylinder and hardline attached, be sure to block off the hardline to avoid fluid spraying out!!

Click on the thumbnails for the full size pic

First we start by removing the 10mm bolts holding the 5th gear pan and removing any leftover CV ends that may have been difficult during transmission removal.
1
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2
Once the gear cover has been removed, you will now have access to 5th gear and the primary and secondary shaft locknuts. Unstake the locknuts and remove. (this may require an airgun)
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3
Once you remove the locknuts, remove the top 2 gears, pay close attention to the order of the parts when removing them. The gears lift up and off the shafts with ease. It is a good idea when removing your parts, to lay them out on your bench in the order they came off and in groups of where they came off of.
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4
Now to remove the fork arm. First, with a punch, remove the pin sleeve locking the arm to the shaft. Then lift the fork arm off the shaft. Again, paying close attention to the order of the parts.

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5
Once the fork arm is removed, you can now remove the 5th gears. They just slide up and off the shafts.

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6
Now we move to the outer casing. Remove these two 12mm bolts. One is holding the reverse gear shaft, the other holds the secondary shaft. Then remove the 14mm bolt, this is holding a small spring and ball bearing for the reverse gear lever. Using a magnetic pickup tool, remove the spring, then remove the ball bearing. The remove the (x15) 15mm case bolts and lift the top section of the case off. You may need to wiggle it around to free the primary and secondary shafts.

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7
With the top case removed, you should have nice clean internal parts.
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8
Now that the internals are exposed, we can start to systematically remove them. We start with the reverse gear. NOTE: the bolt attched to it, is the same bolt removed from the outer case a few steps earlier. In order to keep the parts together, we threaded the bolt into it to make sure it went back in the same place.
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9
Now we move to the 5th gear/Reverse shifting rod. Remove the 10mm bolt locking the rod to it’s base.
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10
Then remove the rod, by wiggling it up and out, then remove the base. Having your parts laid out neatly will go along way to a much easier rebuild.

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11
Now we move to the internal shift lever. First thing, is to remove the locking pin. Press on the outside of the internal cylinder with your finger to release pressure on the pin and it’ll slide out nice and easy. The screwdriver slot on it is only used to help re-align the locking pin hole during reassembly.
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12
Then reach in with your finger, under the fork and behind the diff gear ring and push the cylinder out from the backside.
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13
You can now remove the lever. It rests on 2 spherical pivot points. Once removed, re-insert the cylinder and place it on your workbench in the same orientation it was in. Don’t lose the locking pin.

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14
Now comes the dirtiest part of the job...the magnetic drain plug ring. Remove the drain plug bolt, then just grab the magnetic ring and pull out.
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15
Now we move to the fork arm shifter pivot base. This part can be a bit tricky. It really pays to have a pick tool set handy. There is a spring and ball bearing inside the little cylinder. There is an access hole in the top where you can see the spring coils. You need the very fine tipped pick tool here, as you need to grab the coil behind the last coil you see through the access hole. Otherwise, the spring will not compress enough to allow the ball to retract and let the shifter pivot base loose. You'll need to hold the spring back as you remove the fork arm from it's socket in the case. Take extra care, because if that spring releases, you could be in for a long search for the ball bearing!!! Once you have the fork arm removed, using your magnetic tool, remove the ball and spring and set them aside on your workbench.

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16
Your transmission will now look like this with the fork arm removed.

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Now we can remove the secondary shaft. Lift and tilt the differential, then tilt and pull up on the secondary shaft to remove it. Pay close attention to any washers or rings and keep them in the proper order.

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Now remove the differential by simply lifting it out.

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It has been discussed and shown, that a small portion of the internal case must be ground down in order for the LSD to fit and spin freely. This info comes from the 4cyl BP Protege and Escort GT transmissions, as well as the MX3 GS but as you can see in the first 2 pics, this ProbeGT transmission already has that spot ground down from the factory, so this mod was not needed. The 3rd pic shows where the BP 4cyl transmissions have been grinded for the LSD.

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This concludes segment #1.
Good Job!! :bigthumbup:








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Segment #2: LSD and 5th Gear Parts

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When purchasing the LSD, you'll want to also get some new parts to go along with it. This is where being a member of MMS (Mazdaspeed Motorsports) comes in handy....the parts are not only cheaper, but you are able to order them all online. Shipping has always been incredibally fast.

It has also been discussed and documented about the earlier versions of the LSD having a weak point. The rivets used to hold the ring gear to the differential case. The ring gear breaks away from the differential case, rendering the LSD useless. Later and current versions have been upgraded with stronger rivets, but since this trasmission will see 99% of it's use on the track racing, and see close to 200whp, the ring gear and pin have been welded in place.

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Part 1: LSD Parts Needed


[MSP] Mazdaspeed Protege LSD
Differential & Ring Gear
[strike]GS01-27-190A[/strike]
NEW PART NUMBER - GSY1-27-190
QTY = 1

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23
Primary Shaft Lock Nut
F520-17-628
QTY=1

Secondary Shaft Lock Nut
[strike]F521-17-628A[/strike]
NEW PART NUMBER: G501-17-629A
QTY=1

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24
Speedo Drive Gear
G501-17-341A
QTY=1

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The speedo drive gear will need to be be modified to fit the case and allow the carrier bearing to seat properly. The gear tabs are offset and it must be installed properly. When looking at the gear, the tabs sit flush to the carrier bearings seat. You'll notice on one side of the gear, there are 6 small square notches on the face, But on the otherside, there are 2 larger square notches. The side with the 2 larger square notches faces up. These notches are there to allow the bearing removal tool access under the carrier bearing to pry it off.

More details and pics can be seen in Segment #3: Rebuild


25
Carrier Bearings
G5R0-27-350B
QTY=2

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The carrier bearings need to be pressed onto the differential. For those who do not have a hydraulic press, the services of a machine shop will be needed. Make sure you hang out and show them the correct placement of the speedo drive gear, otherwise, once pressed on, the bearing will not spin freely and a new drive gear and bearing will need to be purchased as they will be destroyed when removing them.


Part 2: 5th Gear Parts Needed

Only 2 parts are needed for the 5th gear swap. The 2 gears themsleves. This is a direct swap and could even be done with the transmission still in the car.

Mazda MX6 or 626 Sourced 5th gear Swap
5th Gear #1
(Primary Shaft gear)
[strike]G560-17-611A[/strike]
NEW PART NUMBER - G560-17-611C
QTY: 1
26
5th Gear #2
(Secondary Shaft gear)
G514-17-308
QTY: 1

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Segment #3: Rebuild

27
Installing the speedo drive gear and carrier bearings. The drive gear tabs will need to be filed/grinded to allow the carrier bearing to seat properly and flush. The Mazdaspeed Protege does not use a speedo gear ring. It gets it's readings from the ABS sensor(s), so the LSD is not machined to accept the speedo gear ring needed for non-ABS cars.

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28
GOOD
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BAD
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30
Once you have your speedo drive gear and carrier bearings installed on the differential, it's time to re-assemble the transmission. Start by removing the old carriers the old bearings ran in. This may require a special pull tool. Be carefull not to damage the transmission case, remember it's aluminum!
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31
Now you can drop the LSD into place. Make sure to add some assembly lube to the carriers and the bearings.

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Now, by lifting and tilting the LSD, slide the secondary shaft into it's carrier.





33
Now re-install the internal shift lever, remembering it's proper orientaion, place it on the spherical pivot balls, re-install the cylinder and locking pin.

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34
Now re-install the spring and ball. The spring goes in first, then the ball. It may be easier to remove the base from the fork arm and use it to hold the spring and ball while you install the fork arm. To remove the base, use a punch to remove the sleeve pin and slide the rod out.

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35
Now install the fork arm back into the base and re-install the sleeve pin

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36
Re-install the 5th gear/Reverse rod and thread in the 10mm bolt

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37
Re-install the reverse gear. Remove the bolt once it's installed. It will be installed from the outside through the case. The small fluid pipe was removed after the teardown and cleaned out. So go ahead and re-install it now.

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38
Don't forget to re-install the magnetic drain ring!! Clean it off thuroughly and just drop it in.

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Once it's all together, you'll need to fiddle with the shifter (on the outside of the case, where the actual shifter linkage attaches to) and using a screwdriver or similar tool for leverage, shift through the gears ensuring all gears are shifting smooth. You may need to install and remove the outter case a few times, as without the case, the shafts can move around and simulate bad or notchy shifting.
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Once you are satisfied the gears all shift smoothly, it's time to reinstall the outter case for good. Before doing so, use a razorblade to scrape away any excess old gasket sealent or material. Then using a 3M scotchbrite pad, give it a final cleanup.

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40
With the outter case re-installed, it's time to thread in the 12mm bolts we removed earlier and thread in all the large 15mm bolts that hold the case together. Don't forget to re-install the spring and ball into the case for the reverse lever!! [14mm bolt] The ball goes in first, then the spring.

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41
Now comes the 5th gear swap part...simply slide the new gears over the shaft and re-install the fork arm and sleeve pin. Pay very close attention to the syncros. It's very important that they are seated properly. If you look closely, they are notched in such a way, that they only fit in one way....the right way ;)

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42
Thread on the new locking nuts and tighten them. [27mm and 32mm] Hold off on staking the nuts untill you are fully satisfied the trasmission is in good working order and you have not forgotten any parts or to apply lube to the bearings and carriers.

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43
Using the same method to clean the mating surfaces of the case, scrape away all the old gasket/silicone from the case and 5th gear cover pan surfaces and do a final clean with a 3M scotchbrite pad. Apply some Ultra-Grey silicone to the mating surfaces and install all the bolts.

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44
Re-install the cover pan bolts and tighten.

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Segment #3 is now complete
Good Job!!:bigthumbup:

Now go and enjoy your new LSD and 5th gear!!


Segment #4: Notes and Tips


Axles
4cyl Applications [BG and EC chassis]
MX3 GS, MX6, 626, ProbeGT all use the same differential side spline counts on the axles (28)
If using this in a BG or EC chassis, you cannot use the MX6/626 or ProbeGT axles, they are too long, the MX3 GS axles should be used. The hub spline count is the same for the EC and BG chassis cars (26) and Alternatively, you can source a set of KIA Sephia axles from a BP equipped car, as well as the KIA Intermediate Shaft. These are also 28/26 spline counts.

V6 Applications [BG and EC chassis]
Again, must use the MX3 GS or KIA Sephia axles, but can use any Intermediate shaft from the above listed K-series V6 cars. They all share the same 28/26 spline counts.


Gear Ratios
MX3 GS | ProbeGT
Both share the same shorter gearing as the BP 4cyl G-series cars.

MX6 | 626
Both share taller gearing, similar to the F-series trans. These are also the cars to source 5th gear for the swap.


Internals
This info was sourced from this Probetalk thread. As well as info from Gro_Harlem who has done the ZX2 internal parts swap.

For a stronger transmission, look for a 1997+ Ford Escort w/SPI DOHC and the 1998+ Ford ZX2 w/zetec DOHC. These cars also use a G-series trans. The case cannot interchange, neither can the differential, but all the internals can be swapped over. It's been said the Escort/ZX2 trans weak point is the spider gears in the differential, since you will use your current differential or the MSP LSD, that eliminates the problem. The main reason for this swap, are different gear ratios, stronger gears and syncros.

It's also noted that the Ford Escape used a G-series trans. Unknown as to what years or if it was the FWD and/or AWD models.



Reference Threads:
OEM LSD for G-series Trasmissions
Gear Ratio / Speed Calculator
WorkLog: 2.5L KL V6 Swap & Race Build Up [BG Chassis]
G-series vs. F-series Visual Comparrison
Transmission Question



Tips:
Clear a large area on your workbench or floor. Spread out some cardboard and lay down some shop towels. It'll help to have a large area to set down the parts, especially if you cannot walk around the workbench and have to move the transmission around alot.

It really helps to have a friend lend a hand.

Plan ahead. Make sure to have all the parts and tools ON HAND and have the bearings pre-pressed on if you do not have a press before starting.

Take your time, the transmission has many intricate parts, don't force anything or pry on the gears.

Have an FSM or repair manual on hand.

Don't take apart more than is needed to install the LSD and 5th Gears. Unless you need an overhaul, don't mess with it.

Lay out all the parts you remove on shop towels neatly and in the order they came out. This not only helps to re-install them later, but keeps the parts clean and free from possible damage. If you leave the parts out for an extended period of time, cover them up with shop towels or plastic garbage bags. Use plastic baggies with labels for the bolts and other hardware.

If you do not have a friend with a hydraulic press, make sure you chose your machine shop carefully and make sure they know 100% the correct placement of the speedo drive gear. Watch them do it!! Don't take it to Joe Grande!! It'll save you the headache of buying new parts and getting held up on completing the job.

Segement #5: Tools & Materials Needed


Tools:
Ratchit and socket set [10mm, 12mm, 14mm, 15mm, 27mm, 32mm]
Air/Electric Impact Gun
Pick Tool Set
Magnetic tip Pickup Tool
Punch Tool
Hydraulic Press
Screwdriver or similar tool (Just needs to be able to slip through the shifter rod sleeve to act as the shifter for testing)
Bearing Carrier Remover/Puller Tool

Materials:
Ultra-Grey Silicone Gasket Sealant
Assembly Lube/Bearing Grease
Razor Blades
3M Scotchbrite Pad
Garbage bags/Plastic/Cardboard
Shop Towels
Gloves
 
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thanks for pointing out that they went down. i have them saved on my computer and i will put them in later today
 
Awesome!
Now all I have to do is cut and paste into the text... in the appropriate place... :-/
 
Awesome!
Now all I have to do is cut and paste into the text... in the appropriate place... :-/

now you know why its taking me so long. it is annoying so i've been procrastinating

anyway i just finished organising the pictures. unfortunatley i still have 3 pictures unaccounted so i need to find out where they belong. and then i have to upload them to photobucket. if you go to the link you will see that i started to upload some of the steps.
 
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