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Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 11th, 2009, 2:52 am
by ionic1000
Is there a machine shop in your area? They may be able to extend the splines for you. I think that would be the best solution to the argument that wytbishop brought forth.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 11th, 2009, 9:04 am
by Ryan
That would work IF they extended shaft wouldn't extend too far and mess with the rotating parts of the LSD itself. This would = kablooie LSD

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 11th, 2009, 9:35 am
by wytbishop
Can't make the shaft longer, need to cut the splines further down the shaft. Ionic is right.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 11th, 2009, 10:11 pm
by ganue
All great solutions and comments. I looked all over and thought someone would have solved this one by now...can't even find a good yoda post!!!

Here's the right thing to do - find the halfshafts that go with the trans...problem is that the JDM house rips the vin number off all of everythning they sell so I can't trace the car source. It has to be either a JDM MX-6 or a Eunos 30x with the LSD option.

Have an email into a couple places poking around for originals. Anyone good at katakana??

Trying to get the car on the road while I find the "more" correct answer.

A couple thoughts though....

1) wytbishop - thanks for following what is developing into a saga. The production shaft is already cut down to the root where the spline ends and the shaft begins. I am hoping that extending the length of the root diameter is a small change in capacity. We'll find out - remember we are behind a ZE now so the added stress will certainly be there.
2) As far as surface area and spline contact area, it should actually be the same as the original. The shaft will move inboard and there is more spline lentgh available. Also, if you look closely at the shaft, you can see the witness marks of contact with the old trans...certainly not 100% of the available surface...should be a small change if any but with the added torque, could certainly be amplified.
3) No obvious issue with contact to rotating parts. There is (my guess) about 10-15 mm separating the left and right halfshaft ends...

I was able to get one good pic last night....from the right side looking into the trans and the fully engaged lefthand shaft..green stuff is a little water-based paint I tried to verify where the contact area was.....all cleaned up now....

Image

Worst case....a new intermediate shaft....I'm willing to take the bet for now.....

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 14th, 2009, 1:12 am
by ionic1000
I noticed that in that picture the splines do not continue to the end and if it is the same thing on the other side then the option of grinding down to the outer diameter may still be on the table. I think you should measure the splines inside to get a better idea! This might turn out to be the quick fix you were looking for! Man I hope it works because this could help everyone wanting to go to LSD!

Again please forgive me if I'm wrong! :D

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 14th, 2009, 10:04 am
by ganue
I'm actually now leaning toward thinking that the intermediate shaft is bottoming out on the end of the trans splines. In the pic you see a clear end of the splines inboard and the inboard section is cut at the larger diameter of the shaft spline. Now I'm thinking all I need to do is grind off a couple mm of the spline end - they are effectively unused (form a torque carrying point of view) anyway if you look at the wear pattern when it was mated to the K8 trans...

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 14th, 2009, 11:45 am
by wytbishop
You have a caliper. Measure the depth from the end of the internal spline up to the surface of the seal and compare it to the length of the shaft from the seal surface to the end of the shaft.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 15th, 2009, 3:56 am
by projectB10
There is a lot of information on the various forums about this. I give you that its a little difficult to dig out.

This is a useful thread. http://www.mx-3.com/phpBB3/viewtopic.ph ... t=kiwi+mx3" onclick="window.open(this.href);return false;

Kiwi_mx3 or Kiwimx3 (he has two user names) is a guy by the name of Matt. He knows his stuff and still frequents this forum from time to time. He is very helpful if you PM him and shares what he knows (which is a LOT!). He might be able to help you with the work necessary to get a solution your way (converting non LSD axles to fit).

I have installed an ex MX6 LSD equipped transaxle in my Presso (MX3). I purchased it complete with axles but had to use a Mazda Lantis set (different spline count at the hub ends). They are relatively easy to find here in NZ.

I'll post up some pic links for you to have a look at. They show the types of axles you are after. At the very least it will give you a reference point to work to.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 15th, 2009, 4:03 am
by projectB10
Ok another useful thread ex Kiwi_mx3.

http://www.mx-3.com/phpBB3/viewtopic.ph ... t=kiwi+mx3" onclick="window.open(this.href);return false;

My pic upload is taking forever. ............I'll get some pics up when its finished.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 15th, 2009, 5:26 am
by hgallegos915
projectB10 wrote:There is a lot of information on the various forums about this. I give you that its a little difficult to dig out.

This is a useful thread. http://www.mx-3.com/phpBB3/viewtopic.ph ... t=kiwi+mx3" onclick="window.open(this.href);return false;

Kiwi_mx3 or Kiwimx3 (he has two user names) is a guy by the name of Matt. He knows his stuff and still frequents this forum from time to time. He is very helpful if you PM him and shares what he knows (which is a LOT!). He might be able to help you with the work necessary to get a solution your way (converting non LSD axles to fit).

I have installed an ex MX6 LSD equipped transaxle in my Presso (MX3). I purchased it complete with axles but had to use a Mazda Lantis set (different spline count at the hub ends). They are relatively easy to find here in NZ.

I'll post up some pic links for you to have a look at. They show the types of axles you are after. At the very least it will give you a reference point to work to.

any way you can get us some?

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 15th, 2009, 5:30 am
by projectB10
OK here's the update for everyone....not completely done yet but here's the plan:

1) Spline count between the stock and LSD transmission are the same so let's put that to rest - at least for the trans I got.
2) Driver's side halfshaft fits fine. However, I do not believe the circlip is properly seated in the void in the transmission. We'll see how fast, if at all, the trans fluid is lost.
3) Passenger side intermediate shaft, fortunately, is laterally located by the three bolts to the engine block so there is not a circlip in the transmission. The problem is that the chamfer on the outboard side of the spline end bottoms out on the spline in the trans about 3mm short of being able to get the three bolts through the non-rotating bearing mount to the transmission. This point on the shaft is far from the seal surface so, i will be grinding the chamfer to allow about 3mm more of spline interface. This moves the intermediate shaft inboard to allow the bolts to the engine block to line up. Then all should be good.
Spline count at the transaxle end is the same MX6/MX3 in my experience (28).
Drivers side axle will fit just fine BUT the circlip will not seat at all and the axle will pull out and you will have a mess on your hands real quick.
The open diff MX3 intermediate axle will not fit as it too long.
If you can picture an imaginary centre line to the chassis (running front to rear) with the open diff centred on that line …. The LSD equipped transaxle moves the diff centre line off that centre line slightly to the non driver’s side in the (context of your NA left hand drive cars). That means when installing a factory viscous LSD transaxle in a non LSD equipped MX3 you must have the right drivers side and intermediate axles other wise it will not fit (at least that’s my experience).

Thats what Matt is on about in his old post...how to extend or lengthen an open diff axle to fit.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 18th, 2009, 12:15 am
by ganue
OK - I understand the driver's (left for me) side issue and will watch closely.
Pasenger's side (right) issue is resolved. By machining about 2mm from the largest diameter step the the next diameter step, it fit just fine. Bolted in and drove the car tonight and all is good - BUT - didn't stress anything yet...will update when I lose the driver's side...

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 18th, 2009, 4:32 am
by kiwimx3
Edited..

I have yet to comfirm however a little bird told me mazada proceed (marvie) 4x4 stub shafts
might work or any of the MPV's that are 4WD.

I am yet to comfirm this, Im currently using MX6 6 ball CV joints, and axles with a Mazspeed LSD

The stub shaft needs to be locked into the dif, and the axle needs to be able to float through out
the full suspenion travel.

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 20th, 2009, 1:09 am
by ganue
OK - I'll try to be short - I think I have this all figured out. "Some" of you guys are "mostly" correct.

1) The LSD trans I have is probably from a Lantis that sat behind a KFZE during its life in Japan. The gear ratios, it turns out, are the same as the MX-3 based on engine rpm matching in both my cars (one a stock GS-SE and this monster I am creating - the other GS-SE with the ZE and LSD).
2) Right side intermediate and half shaft:
Look carefully at this picture from the MX-6 forum:

Image

Note the intermediate shaft and compare it to my pic earlier. The splines in the LSD transmission are about 3mm toward the center (inboard) of the car on the right side (passenger side in North America) compared to the original transmission. By machining my intermediate shaft to make up the 3mm difference in spacing between the factory MX-3 trans and the LSD it fit like a glove and no leaks. Because I made up the difference with the intermediate shaft, the factory half shaft fit on the right side.
3) Left side half shaft: In earlier posted pictures you can see that the left halfshaft is not in all the way. This is what is preventing the circlip from engaging. An educated assumption is that the left side spline is also inboard by about 3mm which explains the visible spline remaining in the picture AND why the clip is not in place. So far my solution is to find a Lantis left side half shaft. This is my new goal while I gingerly drive the car to avoid the left side popping out and making a BIG mess. Note: this is not my daily driver so it won't get driven extensively until this is fixed.

Post questions - I'm trying to make this thread the definitive answer to the infamous LSD question....

Re: MX6 lsd trans in a GS? CV joints ok?

Posted: June 20th, 2009, 5:10 am
by projectB10
This might help... it a pic of an MX6 LSD CV axle end with a ruler for a rough measurement of length. I understand the sprial grove is important for the lubrication of the diff.
Image