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Clearance for Transmission

I’m preparing to remove the automatic transmission from a 98 Mazda Protégé to replace the rear main oil seal. My concern: my jack only goes up to 15.5 inches and the transmission jack (haven’t decided which one to get yet ) will add a few inches so I’m not sure if I will have enough room to roll the tranny out. So does anyone know the diameter/horizontal height of the transmission in this car or how I can find out? Common sense tells me to just go out and measure but I don’t think I could get an accurate measurement without having to remove a bunch of parts first. I would really love to have this all figured out before I start taking things apart.

Why do you want to remove the transmission from under the vehicle? You’re not replacing it.

Just lower the transmission and move it out of the way where it allows you to gain access to the rear main seal.


The manual says to roll it out from under the car but you’re right, all I probably need to do is
just move it over enough to make enough room to pull the old seal and put a new one in. That actually crossed my mind the other day but I trust the manual more than my instincts sometimes.

Off topic but do you happen to know if any of the aftermarket seals are of better quality than the one that came with the car from the factory? Since the OEM seal didn’t last I wonder if
I could find a better quality one but then again after 185k miles probably any brand of seal could/would start to fail.

And have you ever removed a transmission from this particular model or one similar? If you have, can you give some pointers as to whether it’s better to tilt the transmission or to tilt the engine when it comes time to separating it from the block. (I’ve read about people doing it different ways). And should I be prepared to replace torque converter seals, transmission seals etc. My manual doesn’t mention anything about these things.

I want to be thoroughly prepared before beginning this repair just in case I don’t have access to another car for making runs to and from the auto parts store after I’m hours into the job. So any advice or pointers would be much appreciated.

Call parts stores and ask if they sell a resilient rear main seal for your engine.

These special seals reposition the seal on the crankshaft away from normal position of the OEM seal if the crankshaft is worn at that area. These seals were also designed to be able to tolerate if the crankshaft rotated eccentrically instead concentrically.

Depending on clearance, nothing may have to tipped. But if it’s required, I slightly tip the engine and transmission and then remove the transmission.

I’ve removed/installed so many transmissions over the years I can’t recall if I’ve ever did it on a Mazda. After a while they all look the same.


Ok, here’s my plan. I’ll purchase both a resilient seal and an OEM seal before I begin. If the crankshaft doesn’t appear to be worn I’ll just go ahead and install the OEM but If it is worn, then I’ll use the resilient seal. Does this sound like a good plan? Or should I use the resilient seal regardless of the condition of the shaft?

I always installed a resilient rear main seal.

Do you know for sure if the crankshaft is rotating concentrically?


I have no clue how it’s rotating.

I searched online for ‘‘resilient rear main seal’’ but didn’t come up with much. Do you know if it’s referred to by any other names?

Sometimes they’re called offset lip rear main seals.


Here’s the one for your engine.


You might also consider replacing the torque converter seal on the transmission. If you do not, Murphy’s Law says it will start leaking a few weeks later and you will have to tear it all apart again.

Just curious, would mechanics replace the bearing for the transmission input shaft/flywheel-flexplate connection at the same time too? Does the flywheel-flexplate have to be removed as part of replacing the engine rear seal?

Automatics don’t use a pilot bearing. And, yes. The flex plate needs to be removed to access the rear main seal.

I wonder if the factory manual calls for dropping the engine/transaxle as a unit.

@"Rod Knox"‌


Be it a manual or automatic, the transmission can be removed by itself.


Depending on what has to be removed you may also need to hang the engine to support it while the transmission is out.

The engine definitely needs to be supported. No doubt about it. Three of the motor mounts will be removed.
I was planning on supporting the engine with a bottle jack and a 2 X 4 on the engine oil pan.
Not sure if that’s the best way though; especially if the engine/transmission require a ‘‘shift’’ to be separated. Thoughts? Would it be easier to shift if it was supported from above?

@Tester. The manual calls for a special service tool to be put in where the drive shafts plug into the transmission to keep the gears in place while the drive shafts are removed. In all your years of removing transmissions did you ever find it necessary to use these special service tools?

It is much safer and much easier to work with the engine weight supported from above. And yes, it is advisable to install stubs into the differential side gears when both CV axles are out at the same time to prevent the side gears from turning out of position.

Some Fords also require that plugs be inserted into the transmission after removing the half shafts to prevent the side gears from falling out of their positions.

So yes, I have those plugs.


So as long as I’m able to leave at least one of the CV axles in the transmission I shouldn’t need to use the plugs? Because I’m not even sure I can find these plugs and if I get them from Mazda they’ll charge an arm and a leg.

Do either of you guys know where I could find a set of aftermarket diff. plugs? I’ll keep searching online but I haven’t had much luck so far.

And too bad I threw out the drive shaft I recently replaced. I bet I could have used it to make plugs. :frowning:

You can purchase them individually.

You just need to know the diameter of the half shaft.