M50D 5'th/Rev upgrade kit

[DangerRanger]

Just rebuilt a Mazda 5-speed and put the 5'th/rev update kit in it(30 teeth vs. 36 teeth). The kit came with new shifting fork, gears, and all. My question is, what is the proper way to adjust the position of the pivot on the 5'th/rev lever? I figure it's just an eyeball thing, but the trouble is the truck is mobile and everything is good except it won't stay in overdrive. DOH!! Oh yeah, I was supposed to adjust that earlier. Does anyone have an easy way to get this close enough to work. I just don't want to wear anything out prematurely

 

[Taragon]

The 5th/Rev shift collar has a dot on it that you are supposed to see as you are assembling the trans.

If that dot doesnt face rearward, nothing you do will help it.

If you are trying to adjust something, you screwed up the dot position. Re-do the entire install, but you can use the same parts, you just need to simply flip that syncro hub

 

[DangerRanger]

Now where were you at a couple of days ago, huh????

Well, sh*t.....I don't know for sure about the dot. I remember on the OD of the slider there was a beveled edge on one side and the other side had a machined groove in it. Kinda looked like the groove gave it clearance for something. I believe I put the bevel towards the front. correct?

Since I've got the 35's, not staying in overdrive isn't a big deal, but will this hurt anything else? Reverse works fine. I really don't want to do this again yet.

 

[Taragon]

If reverse works perfectly, and it FEELS like it goes into OD, but kicks out the second you let off the clutch, the dot is backwards.

I learned the hard way too man....dont feel bad!

 

[Mutant Pony]

Oh yeah, I remember that. I was tring to figure out what you meant by adjusting it. I have never installed this upgrade kit and was wondering if it came with something different. I have installed the slider bacwards before and caught it before I finished the assembly. That really sucks now that it is put together, you have to tear it all back down again.

 

[DangerRanger]

Oh yeah, I remember that. I was tring to figure out what you meant by adjusting it.


The adjustment is for the pivot position of the 5'th/rev shift fork. There just ain't quite enough there to correct a mis-assembled part.
This freaking thing seems like it gets heavier every time I take it out!!

 

[fixizin]

Danger, where'd you get the rebuild kit?

Also, do I understand you now have a "taller" 5th gear?

What are the ratios of this kit?

Thanks in advance.

 

[AllanD]

No the ratio of the update parts are the same what is different is the number of synchro "dog" teeth that engage the synchro collar.

The early 36tooth setups were relatively gfragile and prone to having the teeth on the collar "blur over".

the 30-tooth parts were a "correction" to that problem.

BTW, if you ever "upgrade" a transmission with those later parts and it won't go into reverse it's because the kit didn't oinclude a new stub shaft for the reverse idler gear.

there is a clearance notch on the newer part that eliminated interference between
the later synchro collar and the thrust face on the idler shaft.

with a steady hand and a freshly dressed 6" grinding wheel on your bench grinder
you can correct this issue, but I recommend you have several early shafts on hand so you can practice....

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[fixizin]

AllanD(ude)! Thanks for the detailed feedback and cautionary tales borne of hard knocks! Your descriptions are very detailed and I know exactly what you mean just from looking at those rebuild pics.

I have one of the '99 M5ODs made pre-11/99 that has the issue with the 3rd gear brass blocking ring. IIRC this was covered in a TSBulletin numbered either 123-xxx or 321-xxx... the mofos at FoMo felt no obligation to fix this under warranty.

One day I will either fix this myself or swap out the whole thing for a reputable rebuild. If I do it myself, I'm certainly going to upgrade more than one blocking ring while I have it torn down.

And even if I punt, and let someone else do the dirty, it's still a huge advantage to be able to talk nitty-gritty internals... don't want to be one of the sheeple majority whose eyes glaze over when the tranny shop guys BS about the Flugelbinder valve, and then get stuck with the inflated invoice... lol.

PS: Do you have sources for these upgrade/rebuild kits? The oft-mentioned 'Southern Gear' seems to have folded up shop.