IRS Transaxle Rebuild

[Casting Timmy]

I will keep working on this as I have time and learn more, but I thought I would share what I have started. I hope to add a assembly section and hopefully a list of upgrades....the list of upgrades I can hopefully get help from others reading and adding to this. The last couple of sections I need to expand on as well...work is picking up again so I don't know how fast I will always be at updating this.

Please review and let me know what you think

Thanks Tim

Drain gear oil
17mm Hex is required, some prefer Hex wrench and others use socket.
Remove nose cone and hockey stick together
Nuts are ??mm

Remove Carrier Nuts
The press fit of everything holds it on without the nuts and waskers in place. Nuts are 13mm

Remove drive flanges
Remove seal or dig out silicone as some use silicone instead of facotry seal. Use wood and pry bars to pry off flange, wood keeps case from getting damaged. Small homemade tool can also be used, need to show pictures of this.

Remove Diff Cover(s) and Diff
Think if diff will fall out with how the transaxle is mounted when removing side cover, you don't want to drop it…especially on your foot. Cover only can be removed using punch or shaft and hammer by hitting cover tabs on each side alternatively until cover is off. A simpler trick can be using a plastic mallet or something between a metal hammer and the diff output shaft to use the diff to push off the opposite side cover. This will remove the diff and the side cover at the sametime, but you must remove the ring gear side cover first. (Typically the clutch arm side cover.) Second side cover can be removed using tabs, or using hitting on inside of cover thru the case with something that won’t damage side cover.

Remove input shaft
Remove snap ring off input shaft away from coupler, so coupler can slide forward. Unscrew input shaft from main shaft and then coupler can be removed. Remove snap ring off of input shaft to pull forward thru bearing. Don’t loose stud, store in clutch shaft or other safe place

Remove pinion nut or 4 bolts to pinion plate
Pinion nut takes special tool, or some use hammer and chisel to remove nut. 4 bolts sometimes have metal tabs that need to be unbent so bolts can be removed.

Press out pinion shaft to remove gear set from housing
Can use jack bolt set up. Pry bar and wood on both sides of pry bar. Homemade tool. Watch carrier housing to make sure it's coming off even, it's very easy to miss removing a nut on the carrier housing. Reverse gear can fall out depending on how you remove it. Once carrier housing and gear stacks are removed, the reverse gear and shift tab can be removed.
Remove shift fork bolts

Remove shift fork shafts.
1-2 fork can be removed when the shift fork shaft is removed. 3-4 fork will not come free yet and shift into 3rd to remove shift fork shaft. A punch and hammer can be used to drive the shaft out. Be careful to not lose the balls or oval interlocks as they can fall out when the shaft is removed. Should find 3 balls and 2 oval interlock balls.

Tie shafts together for upcoming press removal
Optional step as this makes it easier for some to handle the shafts

Remove snap ring and washer from mainshaft
Press mainshaft out from carrier housing
Set up will be based on press, factory tool or similar set up will be required with most presses. Shift fork for 3-4 will fall out during pressing or can be taken off afterwards

Mainshaft Breakdown (10 Tooth Version)
Put bearing spreader under 3rd and press off everything at once. Becareful during press out not to let mainshaft hit the ground.

Mainshaft Breakdown (9 Tooth Version, 002/113)
Snap ring, need to research and figure this out again. Becareful during press out not to let mainshaft hit the ground.

Pinion Shaft Breakdown
Use U shaped or bridge tool to press down on 4th gear to allow snap ring removal. Slowly release pressure and now bearing race, 4th, and spring can be removed. Remove snap ring on top of third gear. This snap ring will be a special thickness, do not mix with other snap rings. Pull off most of the components by hand now, be careful in stacking them and keeping them in order for analysis

Should have pinion shaft with nut and 1st gear needle bearing and pinion bearing on it.
Remove nut with special tool to remove needle bearing

4 Bolt Pinion Bearing Removal
Use bearing spreader on inner bearing race and press to remove pinion bearing and 1st gear bearing race

002/113 Pinion Bearing Removal
Research this one, is it the same?

Diff Disassembly
Remove Ring gear bolts, this is easiest with an impact. Using a wrench or rachet will need a method to hold the diff from turning. A wood chisel worked around the outside of gear quickly removes gear from diff. A wood chisel worked around the outside of diff housings, quickly splits housings apart. Spider gears, shims, and side gear shafts can now be removed by hand.

Diff cover has two holes for bearing removal.
Need to figure out tool/ method for this. Can two rods be welded to bar stock?

Diff housing has two under cuts to allow bearing removal
Need to figure out tool/ method for this. Can a simple 2 finger puller work? A couple of press plates would also work here

Diff Bearing and Shim Disassembly
Use simple bearing and race kit installation tool to knock out shims and bearing race at the same time.

Carrier Disassembly
Removing detent spring plugs
Removing bearings

Nose Cone Disassembly
Removing shift rod bearings

Case Disassembly
Removing clutch shaft
Removing starter bushing
Removing clutch shaft bearing
Removing Reverse components

[Stuart Maingot]

Good luck.

[mark tucker]

yes 2 finger puller will work so will a 3 finger puller I just did mine. whats with the funkey spring between 3&4 gears? does any body make a GOOD performance book or something for these trans? somethen that shows all the stuff to do and clearances for it to last & take the power we are putting through them nowdays? does the long dvd show all the tricks/ mods or just how to rebuild?
i made a fixture to hold the gear assy for pressing it out of housing out of some 2x6 pine ( I would rather used 2x8 but this is what I had),cut 9" long(3 of them) and one 10.5 long ( back side screwed to one of the sides&the bottom,sides are also screwed&glued with powergrab and it works perfect and has one of the 9" long peices across the bottom so nutten hit's anything hard. I got anil and put it in my mill to make sure it was square&wacked off about .060" to be sure. I already had a fixture for pressing the gears off,kent more , miller,mtc or some other dealer trans tool fixture cant remember,it's real nice to have.
now to figure out just what all i need for this trans.I thought I had some nos parts....but the 2 nos pinion bearings are for the 4 bolt&I need the big nut pinion bearing.also the 5 nos syncros I have seem to be 2 for 3&4 & dont have a clue what the other3 are for too small on the id for 1&2. but the nos slider I have seems to be the right one for 1/2 and I think the nos reverse gear may also be right,Ill need to do some more measuring to be sure. now to find all the stuff I need.

also.... what the hell is this black slimy crap in these vw trans?????the is the 2nd or 3rd Ive opened up that has been like this.and Ive opened atleast 2 or 3 of them in my life (check out diff,r&p&put hd sides on them) .Ive never had any slime like this in any other trans or rear end Ive done in the past 40 years.was it funkey german geralube or what???

also is any body dfl/moly coating any of these gears?r&p? just wondering

[Casting Timmy]

The long DVD doesn't even show the complete stock rebuild. I really wish I knew of a performance book for these transaxle, I will type up some tricks I have found through searching.

I will add a reassembly and inspection section to this eventually. I know I have some things listed in that already. I'm really hoping someone will chime in with tips for a good street box.

I did notice one box unopened had that black crud you talked about super bad. It took forever to clean that stuff off. Actually in opening up a few old ones it seems reverse is very likely to be screwed up.

Ive read that Weddle and erco make real side covers and the rest of the heavy duty ones are the same weaker pieces not much better than stock.

I thought I read once about eliminating the spring to reduce gear movement and make it stronger, so I need to find out if I remember that right or not.

Weddle will super polish your ring and pinion and that is supposed to help out.

[vwracerdave]

The Bentley repair manuals have a complete chapter with pictures and tools to rebuild a stock transaxle.

Gene Berg technical articles book has a chapter with pictures on performance upgrades
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[mark tucker]

Ive got the bently,but not all the $$ for the fancy tools. and since I cant read I need good big pictures.

[Bruce]

[mcmscott]

[Casting Timmy]

Thanks Bruce and Scott for reading that over. I corrected it to input shaft and also updated the shift shaft removal section to include just using a punch and hammer to drive them out. Hopefully that is an acceptable method, but if not I can update that section as well.

I am trying to see if I can add another section late this week, work is slow for me right now and just doing something there to keep my sanity.

Do you have a list of common upgrades or how to modify gear set up for high performance street use? Or do you just follow the Bentley for gear stack tolerances?

I have seen a 300M input shaft listed with Baja guys, does that help in street applications as well? Also how much preload to run with a weddle side cover on a single side case? Do you run more on a dual side cover case or when using stock covers? I didn't know if the Baja preload increase could be used on the street or not.

Thanks for any advice or help
Tim

[mark tucker]

I cant fine my bently I was reading it and the house remodel got to that room and.......crap.( try to do all my reading in the house and keep books cleaner) Ive ordered wider 4mm pinion shaft needle bearing(front end of pinion)for better pinion support.I havent been able to find a wider rear main shaft bearing,but Im still looking.also trying to find smallpinion/first gear shim, Ill probably remachine the nut to axcept more than 1 shim.also gonna put torringtoin needle thrust bearing on 4th gear. these things sure dont have many thrust shims/washers like I fighure they would.it's driven me nuts (not a far drive).wish i had a pair of those aluminum gear carriers/housings.
is any body taking the small shaft housing with the flanged bearing being loose and boring the housing for the bigger shaft& bearing?thus giving the housing another life?is either one worse at getting loose in the housing?
also the dif has 2 scoops on the end is that not enough oil? or does the super diffs need an exhaust hole?

[mark tucker]

another question...or 2 where do I get the needles to hand pack the bearings& are you guys using longer bearings since the plastic cage is no longer there or are you cutting the ends off the cage's for spacers?thats over 5mm of surface not spreading the load or the bearings can move about from end to end that much..or more.

[mark tucker]

bently still mia. , but I did some checken and fitten......the .88 4th from a small main shaft needs some work as does the clutch/syncro thingy to work togeather, dosent look hard. a whittle hear a whittle there...I might send out for welding the 3/4 hubs&whittleing the 4th gear down a bit for clearance.I think I can do the rest. Ive still got to make a jig for pinion depth&compare the cases.I wish that klinkenberg wasent effed up on the end,Ill go with the g388 instead as it looks great. I still havent found anything that cuts this black slime. 3 hours in the dishwasher and ....no dif,still nasty.so it's tooth brush&bbq cleaner&oven cleaner.

[Casting Timmy]

Are you talking about putting early gears on a late main shaft?
https://weddleindustries.com/tech-info

Weddle has a diagram showing how to modify the gears and the clutch hub to make it work. See the early gears on the super beetle mainshaft article.

Long Enterprises is trying to sell the business, but they would have the hand pack needle bearings. I would assume that weddle does as well. Weddle also sells metal caged bearings for the T1, how does that stack up against the hand pack bearings?

I know the hand pack adds a lot more bearing surface, but I think I also read they can shift to an angle and that's bad. So hopefully someone can chim in about the best bearings to use of hand pack vs metal caged vs stock.

Also you don't need the factory tool to set up the ring and pinion. I read once about using grease and looking at the markings on the gears. The late model trans didn't even have the scribe marks for using the factory tool.

[Casting Timmy]

I have some assembly notes, but a lot of typing I need to do and some stuff to research out some more. Hopefully this helps you out.

Diff Internal Set Up
Stock Gears/ Stock Housing
The 10 tooth spider gears/ 15 tooth side gears are stronger than the 11/17 combination
Need to add a lot of information here

Ring Gear Installation
Heat gear or pull on using bolts in slow draw down pattern criss crossing thru bolt pattern?
Need to find out preferred installation method

Diff to Case Set Up
Replace bearings if needed, if case or diff housing or bearings are different preload needs to be determined.
Bearing races can be removed with simple bearing/ seal driver kit.
Pick the appropriate sized seal driver (flat side) to drive out the bearing race and shims.
Pick the appropriate sized race drive when reinstalling the race and shim(s)
Jam wooden dowel in gears thru side if using turning torque method to keep gears from moving
Can do by hand if experienced, or by using torque wrench that can do running torque measurement.
Preload can be measured by fully torquing both side covers and then removing nuts from one cover and using feeler gage to determine preload.
The amount the cover pops off is the preload in the diff. (I assume this method you want the oring not in the side cover during this step.)
Increasing total amount of shims, increase preload and turning torque
Stock side cover or side covers
Turning torque new bearings ??
Turning torque old bearings ??
-OR-
Stock preload ??
Street preload ??
Drag Racing preload ??
Baja car preload
Drag Race and Baja cars can run more as they are torn down more often to check for damage.
Heavy Duty side cover on diff ring side
Stock preload ??
Street preload ??
Drag Racing preload ??
Baja car preload
Drag Race and Baja cars can run more as they are torn down more often to check for damage.

Determine Pinion Shaft Depth / Ring Gear Backlash
If the pinion gear, bearing, or transaxle changed the pinion depth will have to be reset
The pinion shaft must be at least partially built up, see Pinion shaft build up below
The case must be heated so the pinion bearing can be slid in by hand, but be sure not to burn yourself during the heating/ handling process
4 bolt pinion bearing retainer
Cut the heads off two 10mm bolts to use as guide rods
Install and tighten the bolts in a cross pattern slowly increasing torque of all bolts
002/113 pinion bearing
Look for the notch in the bearing housing, that will be located towards the ring gear side cover
once the bearing gets far enough into the case, you can grab it and align it into the cutout of the case.
Install and torque the pinion nut
Pinion Depth Wear Marks
Stock
Street
Drag Race of Baja
Ring Gear Backlash
Stock .006-.010"
Street .006-.010"
Drag Race or Baja .??? (requires frequent tear down and inspection)
Keep total amount of shims the same, just move shims side to side to adjust backlash.

Pinion Shaft Build Up
Press on Pinion Bearing, preheat bearing and support inner race during pressing.
Install 1st gear thrust washer with the best side away from pinion bearing.
Press on 1st Gear needle bearing race.
Caged 1st Gear Needle Bearing
Lube and Install 1st Gear Needle Bearing
Hand Packed Needle Bearings
Hand packed needle bearings should only be done before installing 1st gear.
Torque Pinion Nut to ?? Ftlbs
Stake Pinion nut to splines in 3 spots evenly spaced around the shaft.
Install 1st gear, may have to install hand packed needles at this time.
Install 1st gear end play shim(s)
Install 1-2 clutch gear
Support Clutch gear with bearing spreader and apply pressure in press
Use feeler gage between 1st gear and 1st gear thrust washer
Needs to be .004-.010" with .006-.008" ideal
Change shim(s) as needed to get correct clearance
4 Bolt Pinion Bearing Retainer
Remove 1-2 clutch hub and shim(s) and 1st gear
Install pinion bearing retainer plate, hole in plate over bearing
Besure to lube 1st gear needle bearings and thrust washer lightly
Replace 1st gear and shim(s)
If using hand packed bearings, must sure they are still in place before adding gear
002/113 Pinion Bearing the retaining portion is part of the bearing, so 1st gear will stay in place.
Be sure to lube 1st gear needle bearings and thrust washer lightly
Install 1st gear syncro, be sure it has a minimum clearance of .xxx"
Assemble 1-2 clutch hub and 1-2 slider, the (solid or hollow) keys are used with the (fill out) springs
The springs should not align to each other side to side, be sure to offset the gap between them.
The shift fork grove goes towards second.
1-2 clutch hub and slider can be assembled in a few different rotations to each other.
Lube the thrust faces of the 1-2 clutch hub
Carefully add this assembly on top of the pinion shaft, the hub keys must align in the 1st gear syncro
Add the 2nd gear syncro, be sure to align with keys.
Lube syncro cone and thrust/ bearing surfaces lightly on second gear.
Install 2nd Gear
Lube and install 2-3 needle bearing
Lube surfaces of 3rd gear and add to stack.
Tap lightly down on 3rd to seat the gear stack together.
Install snap ring and make sure it's fully seated into grove.
Check gap between 3rd gear and snap ring, should be .004" or less.
How to adjust?
Doesn't spring push down on the snap ring?
Install spring over shaft
Add loctite to 4th gear splines and inside bearing race.
Press down on 4th with bridge tool a little.
Tap on bearing race using punch to install bearing race.
Press 4th and tap bearing race alternately until snap ring grove is exposed.
Install snap ring in grove fat side up
Install bearing spreader under 4th and press bearing race to seat against snap ring
Verfiy 1-2 slider can shift by moving up and down, return to neutral when done.
Verfiy 1st and 2nd can rotate.

[mark tucker]

yup thats exzactly what I see needs to be done. I didnt see the hand pack bearings there but the mettle cages ones look nice,I think's Ill get those and a pile of shims too. settinbg pinion depth by pattern is nothing new to me,but not all that easy on these trans. Ill mesure both cases & figure the diferance if any then go from there. so far the books I have say to use the std vw depth then add or subtract from the gear spec....but dosent say the std depth.how stupid.

[Casting Timmy]

58.7mm was the design on early ones according to the Bentley from the face of the pinion gear to the centerline. These have the factory listed offset to get them correct to this dimension.

Late model IRS they stopped marking the offset to get the best fit between gears, and changed the measurement to the back (bearing side) of the pinion gear. It says on these to measure before taking them out of the case so they can be put in another case to the same dimension.

It is funny how all the tech books followed the factory on the transaxle rebuild, it's also weird that no one has made a book or manual on how to build a vw transaxle.

I wish I could get my hands on a manual for a south African, Mexican, or brazil beetle as I've seen it mentioned that Brazil had slightly different gearing. Maybe one of these guys actually got a real rebuild manual.

[mark tucker]

ya I know how to go from back of bearing to the machined pad on pinion,but you still need that spec from the machined pad to dif CL or some sort of spec to go into getting it where it should be. if you have a new gear set you have no old case to mesure it from. there is a spec.I will make a jig, mesure both my cases and go from there....but haveing the vw spec would be nice.I found my bently!!!! when I get back from athens in a week Ill start reading ....yes I can read. I hope the bently book has the spec for the late irs stuff(73+) funny thing the my 73 trans has big shaft&my74 didnt. go figure.
hey the mail man just droped some trans stuff at my door!!!!!woohoo.hmm...bugpoop parts???? (we all know Im not a fan of bugpoop parts,)I gotta check these kind a quick.........hey!!! they never disapoint!!!!! the bug poop 3~4 gear spacer is about .008" too small in dia to fit over the pinion!!!!!but the washer is way too big!!!! Just another low quality bugpack pos that isant made right.Good thing I have a sunnen rod hone and the right size mandrels. I hope empi steps the old bug poop stuff up a few steps in quality.that would be nice.

[mark tucker]

from what i see the 3rd gear clearance is set with the 1st gear shims&3rd gear clip.I will use the thinest clip&2 or more shims at the pinion nut/first gear shim location. the shim that was on there were eaten up badly,one real badly.I dont think 1 shim is a good idea there like these had. I got the spacers to replace the springs between 3~4 gears.

[Casting Timmy]

Mainshaft Build Up
Lube and Install 3rd gear needle bearing
Lube and Install 3rd gear
Earlier 3rds can be added to late model 002/113 shaft if gear is machined.
Hub will have to be machined as well, refer to Weddle tech pages for dimensions on both.
Lube and Install 3rd gear syncro
Lube and Install 3-4 clutch gear
This must be installed correctly, check Bentley and update
Are there different versions?, check Bentley and update
Clutch gear has grove on outside that must face 3rd gear
If slider has a grove on outside it must face 4th gear, no all sliders have grove.
Lube Thrust surfaces
002/113 Mainshaft will have a snap ring here….does the Bentley even cover this?
Need to find out set up for 3rd and snap ring specifics if any
Use hammer and partially install 4th gear needle bearing race onto shaft
Press until it kisses into clutch gear
Raise third gear by hand making sure to align syncro into clutch gear
Fully press making sure everything does bind and can still spin freely
Make sure 3rd has end play of .004"-.010"
Lube and install 4th gear needle bearing
Install 4th gear syncro
Lube and install 4th gear
Install 4th gear thrust washer
Make sure 4th has end play of .004"-.010"
Grind 4th to get more clearance if needed
Bring shafts together and install 3-4 shift fork
Rubber band or tie together if desired to make handling easier
Add gear carrier on top of shafts, lightly start mainshaft into mainshaft bearing
Only tap on inner bearing race
All shift shafts installed might be easier before adding gear sets
This will require partially removing the 1-2 shift shaft later to install the 1-2 shift fork
Install 3-4 shift shaft into 3-4 shift fork
Press mainshaft bearing onto mainshaft by pressing on inner bearing race only
Check 3-4 shift shaft and 3-4 shift fork and pinion shaft/ gears for movement when pressing.
If something starts to not turn freely stop and investigate.
Once fully pressed make sure shift forks are in nuetral, hold one shaft and turn the other.
Make sure all gears rotate.
Sometimes a syncro can get stuck, pry off gear gently with screw driver
If one gear seems stuck do not continue until you get clean nuetral
Place concave washer and snap ring on mainshaft
Press only enough to be able to install snap ring
Make sure the snap ring is fully seated into grove using hammer and punch or pliers
Install 1-2 shift fork by parially removing 1-2 shift shaft
Install reverse linkage and reverse gear
4 bolt pinion bearing retainer
install bolt with cut off head to guide into shift adjustment fixture
install pinion bearing shims so that shafts are in correct relationship to each other during adjustment
002/113 pinion bearing
install pinion bearing shims so that shafts are in correct relationship to each other during adjustment
Carefully install assembly to shift fork jig or old cut up transaxle housing
If using an old transaxle housing probably makes sense to eliminate press fit on pinion bearing for easy removal of assembly from jig.
4 bolt pinion bearing retainer
You can leave the guide bolt in, but install two bolts across from each other to secure into jig
Flat corner on pinion bearing holder goes towards 1-2 shift rail
002/113 pinion bearing
the pinion bearing will have to be rotated and aligned into a cut down transaxle housing
install pinion bearing nut to seat/ align the pinion shaft with the mainshaft
Adjust 1-2 shift fork to have clearance on both sides while in first second, and neutral positions.
Manually move slider to first with loose shift fork on shaft
Lightly tighten bolt and check/ adjust clearance when shifted into other positions
When adjusted the same for all 3 locations tighten bolt to 18 ft-lb
Adjust 3-4 shift fork to have clearance on both sides in third, fourth, and nuetral postions.
Follow same procedure as above.
When adjusted the same for all 3 locations tighten bolt to 18 ft-lb
Adjust Reverse
Shift Reverse shift lever to engage reverse
Verify gears fully engage.
Eye bolt can be adjusted in to reduce slop
Large pins can be made to reduce slop and make reverse feel like a positive gear change
Shift Reverse to nuetral position
Shift into second and ensure .020-.040" clearance between reverse and 1-2 slider

Assembly into Case
Gear Carrier Assembly
Shift into Reverse
4 Bolt Pinion Bearing
Make sure guide bolt or bolts are in place and shims are in correct position.
002/113 Pinion Bearing
Make sure notch will be towards outside of case and shims are in correct position.
Coat gasket if desired and have ready for case

Case Assembly
Heat case so that pinion bearing can be slid into place.
This is very important on the 002/113 pinion bearing as you will have to feel it into the position.
Some press or draw into place with the 4 bolt, but this wears out the important press fit for this bearing

Gear Carrier and Case Assembly
Bring together being sure to align reverse onto reverse shaft and pinion carrier guide bolt if needed.
Can tap lightly on pinion shaft if needed, or even mainshaft to get seated.
Be sure to align 002/113 pinion bearing with notch towards outside!
Once seated ensure clean nuetral (after shifting out of reverse)
4 bolt pinion
Torque to 36ft-lbs
Stake pinion bolt retaining tabs if used, be sure to shift into 1st afterwards to verify tabs are out of the way.
002/113 Pinion Bearing
Torque to ?? Ft-lbs
Tighten Gear Carrier Bolts to 14 ft-lbs
Install pilot shaft into housing
Install snap ring on pilot shaft
Install coupler onto pilot shaft
Screw mainshaft to pilot shaft using coupling stud
Back off 1-2 splines and slide coupler forward
Secure coupler with snap ring
Install Diff cover on none clutch side if required (only dual side cover cases)
Install Diff into transaxle
Install final side cover and clutch tube bracket
Tighten bolts to xx ft-lbs

Drive cups
Add split ring to diff shaft
Install drive cup, sometimes a simple bar with a hole for a bolt is needed to draw it down.
install snap ring
Seal/ retain snap ring with silicone
Install factory seal if desired, but off roaders just use silicone as it helps retain snap ring

[Casting Timmy]

Case/ Side Covers
Single side cover case stronger than dual side cover case
Single sided are 002/113 pinion bearing so require the special tool and are harder to put together.
Side covers with reinforment rings are better than side covers without
Aftermarket billet covers are the strongest, but some are definitely better than others.
Order a cover from Weddle


Super Diff as Compare to Stock 10/15 gear unit
Super Diff comes in two versions 11/17 weak gears and 10/15 strong gears
Does oil hole need to be drilled? Need extra gears and also extra shims to put together
Okay to set gears up as tight as possible even on street box?

Splines are stronger than keyways, stay with splined gear sets…don’t grind 002/113 shaft down for keyway gears

Chromoly pinion nut or bearing flange increases strength and helps reduce pinion movement

Heavy pressure plates increase wear on items and make a stronger clutch pedal
longer arms can be installed from the later years to ease clutch pedal effort
Check clutch hook on pedals in car for wear, the clutch cable will wear threw the hook

Swing axle
Find 10/15 tooth gear internals and make snap ring grove big enough for 2 snap rings
Shim for minimum clearance without gear bind

Pre-runner cars have proven that the stock housing with 10/15 is stronger than the superdiff 11/17 on swingaxles

Polish thrust surfaces of gears in lathe with 400-600 grit sand paper

Yes machining the 3-4 clutch hub, then using a .015 thicker stop washer and machining the gear is a very good way to use a 113 style gear on a 002 m/s. You should also machine the clutch hub(slider hub) for a 091 snapring at the same time. I do this in class 11 trans all the time.
mcmscott

300M input shaft being used as torsion shock absorber by offroaders, does this transfer to the street crowd?

Old article notes, forget source
Off road racers have found they can tighten backlash to almost zero (Requires tear down after each race, do not do in street machine)
Preload can be increased to .020" with stock flexible side covers (Requires tear down after each race, do not do in street machine)
End play of gears set to high side of allowable tolerance to improve oiling

091 first gear conversion