2G Trans Plan Sanity Check

[dwdsm]

Hi, Everyone! Just wanted to get a sanity check for which direction I may take towards having my DSM a fun reliable car for the next 20 years. I have owned this car since 2003 and in it's prime it was very fast locally winning many Flash light drags, clobbering "factory fast" cars at the drag strip, and showing up to a few open track days at the road course. Now with factory cars so capable out of the box, the level has just really jumped to compete even within our own community, and trans parts getting harder to find I'm ready to "retire" the car and get it back to car show/car meet clean. The memories I have with this car are priceless and I'm totally cool with taking the family to get ice cream in it and getting my jollies hearing that wonderful turbo note with the occasional 2-3 gear pull. Last year coming back from a meet I was in the fort pitt tubes with zero other cars which is a rare occasion. I of course decide to give it the beans and a moment after going into 4th 4th gear sheared off all the teeth of my 10 year old Shep stage 3 Trans. The car really needed gone over anyhow as the steering rack, transfer case, and many other things had started leaking or just showing their age from the original build back in the Slowboy Racing Days. With Tim @ TMZs help I collected almost everything including tools to rebuild and have another trans when I get this car back up and running again.

Fast forward a year and a half and I've made progress on a few things for the DSM but still in the middle of the Trans as I am splitting my garage time restoring a Willy's jeep for my neighbor and the furthest I got was assembled clusters. I started to chicken out with the assembly because shimming this to perfection could be a make or break for this car and it's future. I contacted Tim again to see about him finishing this current Trans to get me back to square and he is willing but with the current COVID mess he has been backlogged and it got me thinking that maybe I should try and finish it. I recently found a grindy 2g AWD trans that I purchased to have yet another back up and that gets us to the current time.

At this point I have all the parts to assemble a pretty much stock AWD trans and a backup. I have two paths to take. I can send this trans to Tim and get it done professionally to ensure it's at least assembled to perfection but this eats up what's left of my 2021 budget more then likely. (I have a Toyota MR2 Spyder that is prepped for XSB I also need to leave room for). Then next year have this second trans sent off to do the same.

Or I can suck it up and with all the wonderful information people like Tim have provided get out my Dial indicator and give it a whirl and start the path for saving to get this second one done in a Dogbox to guarantee no more 4th gear explosions. Others that have built their own, have you had any consequences doing so?

The question really is will an essentially factory home built trans hold up to 425whp/350tq car if driven kindly with the occasional rolling pull? Would it be better if it was assembled by one of the best? Or is the lack of Evo 3 trans parts just going to make this one have the same fate?
I am leaning towards pulling up my boot straps and assembling the almost finished one and sending Tim the second in a little over a years time to build a dogbox. Is this plan sound of mind? 16 months from now will I regret it because the parts won't be available to even assemble a dogbox? I'll throw in some pics of the old gal along with the jeep project. It's a fun one to build with the Ford 289 I built to swap in.

 

[92AWDHX40]

A factory hold up, for factory parts, and then some more but no real answer, is it rebuilt, even so you wont know till you get it going and up there. DSM Transmission Rebuild Services (jackstransmissions.com)

Home - TEAM RIP
awd 5 speed transmission are strong? | DSMtuners
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Drivetrain & Clutches (boostinperformance.com)

This should help out .

 

[dwdsm]

I guess I'm more looking for advice on whether it's a sound plan to have two factory transmissions refurbished by a professional or refurbished one myself to buy time to save for a dog box and just be done with it. I probably only put 3,000 mi a year on this car If that.. I'm cool being a spectator at this point, I don't need it to compete with it but I'm still traumatized from shattering 4th gear and just wondering if eventually that would just happen again even at a modest power level. To add to all of it I feel like our window of time to get even a factory rebuild is short because more parts are probably going to be discontinued in the future.

 

[92AWDHX40]

Just get a stock rebuild a lot of us are hammering our dsms on a stock transmission, pick a builder and have it rebuilt, sooner the better. Parts may not be available,

 

[pauleyman]

You're already most if the way there. Why are you concerned about your ability to shim? Its tedious but not difficult.

 

[dwdsm]

You're already most if the way there. Why are you concerned about your ability to shim? Its tedious but not difficult.

Honestly I'm not really sure why I lost confidence. Your right though it's no different then measuring the end play of a crank or shimming the transfer case for the jeep I just rebuilt. I have the FSM and plenty of support here.

 

[AWD-Tony]

It’s not bad at all just tedious x3. Make sure to use the correct solder and shim it indoors so solder gets a good squish.

 

[XC92]

Dial indicator? Don't you mean micrometer? Or do you need both? I'm going to try to fix my iffy 1G AWD trans soon and want to make sure I have all the right tools. I actually have both so I'm wondering if I missed something.

 

[dwdsm]

Obviously I'm the one on here for advice so take it with a grain of salt but I'm pretty sure you need both.. A micrometer for measuring things like your shims and then a dial indicator for measuring shaft play. Tim has a few posts listing all the tools and so far I can attest that you need everything on his list for sure. Obviously I'm at the point of assembling and the only measurement I've done so far is the feeler gauge for the snap ring on the end of the cluster.. I have a backup transmission being shipped today I should do a step-by-step post on it. Maybe then people could chime in and critique what's being done so I can learn a better process and in the end we would have a really nice step-by-step procedure for a rebuild.

 

[pauleyman]

Obviously I'm the one on here for advice so take it with a grain of salt but I'm pretty sure you need both.. A micrometer for measuring things like your shims and then a dial indicator for measuring shaft play. Tim has a few posts listing all the tools and so far I can attest that you need everything on his list for sure. Obviously I'm at the point of assembling and the only measurement I've done so far is the feeler gauge for the snap ring on the end of the cluster.. I have a backup transmission being shipped today I should do a step-by-step post on it. Maybe then people could chime in and critique what's being done so I can learn a better process and in the end we would have a really nice step-by-step procedure for a rebuild.

I'm with you on this one. I use the solder method and a micrometer but I like to back it up and check it with no shims present and a dial indicator. Also for the solder method I do one shaft at a time. I've seen the case flex and honestly I blame the case for failures on high horsepower cars. Nobody wants to install a custom bearing case on lower HP cars but if I were a betting man we would see fewer 3rd gear failures on 4 to 500hp cars. That's my opinion anyway. It stands to reason that axial load increases with our helical gears. Does this flex the bearing plate? I don't know.

 

[XC92]

Thanks to both of you for cluing me in. I recently bought both, plus both kinds of solder, plus a lock ring plier, and can rent or borrow the few things I don't have, like a 36mm socket, separators, bearing and gear press and hydraulic press. I'll probably put it off till spring as I really don't want to work on my car outside in a typical NYC winter, but that gives me time to read up and prep.

 

[pauleyman]

Did you save the old clutch disc. If so cut it up and get the center out of it and weld it to a cheap socket. I bought some junker black oxide socket big enough and had it welded. Custom tool ftw.

 

[XC92]

Did you save the old clutch disc. If so cut it up and get the center out of it and weld it to a cheap socket. I bought some junker black oxide socket big enough and had it welded. Custom tool ftw.

Yes, still have it. I save everything unless I have a good reason not to.

What would I use such a tool for? Is it for when I need to torque down the 36mm nuts, to keep the shafts from turning, or to test out shifts under (very) mild load?

 

[pauleyman]

Loosen and tighten the nuts. Its not necessary but i much prefer it to other methods. Btw you can't test shifts by hand.

 

[XC92]

I understand that the 2 penny method can damage teeth. The putting it into certain gear combos is no good either? I know the FSM advises using a tool that does what this one does, so makes sense.

Why can't you shift by hand, if you have 2 people? Can't one person use this tool turn the input and the other person does the shifting with the select and shift levers?

Btw, with the new clutch and slave in and the car getting into gear and moving, same problem as when it last ran over 5 years ago, pops out of first. So, yeah, it's gotta come out again and be fixed right. Hopefully it's not TOO bad. But, whatever it is, it is, and I'll deal with it.

 

[dwdsm]

Did you save the old clutch disc. If so cut it up and get the center out of it and weld it to a cheap socket. I bought some junker black oxide socket big enough and had it welded. Custom tool ftw.

I did the same thing and it made breaking that nut loose a breeze. It's really ghetto as I just used an old input shaft and some random scrap but it works well for sure.

 

[XC92]

I did the same thing and it made breaking that nut loose a breeze. It's really ghetto as I just used an old input shaft and some random scrap but it works well for sure.

How does this work with an input shaft? Where do you insert it?

Btw, while on the topic of tool hacks, any suggestions for keeping the rubber insert inside a spark plug socket from detaching? Happens too often to me. Crazy glue? Gorilla glue? Epoxy? Contact cement?

Also, how to keep the extension from coming out the socket? I'm thinking of inserting a loop of thin craft wire inside that I could pull on if necessary. Why are these so poorly designed?

 

[92AWDHX40]

Nothing to do about that coming out just apply force at a angle as you take it out, or get another extension tool and try it out.

 

[pauleyman]

I understand that the 2 penny method can damage teeth. The putting it into certain gear combos is no good either? I know the FSM advises using a tool that does what this one does, so makes sense.

Why can't you shift by hand, if you have 2 people? Can't one person use this tool turn the input and the other person does the shifting with the select and shift levers?

Btw, with the new clutch and slave in and the car getting into gear and moving, same problem as when it last ran over 5 years ago, pops out of first. So, yeah, it's gotta come out again and be fixed right. Hopefully it's not TOO bad. But, whatever it is, it is, and I'll deal with it.

Think about it. Idle alone is 700rpm and if you dont keep it up its enough to stall an engine in first gear. You cant make that rpm or torque by hand.

 

[AWD-Tony]

Use wd 40/dielectric grease/any lube on the rubber and it’ll come off easy. I use dielectric grease bc it lasts longer.

 

[XC92]

The idea is for it to NOT come off easy, though. It's supposed to stay on and grab the plug for removal while also staying in the socket AND come off the plug after reinstallation.

Only way I can see of that working is to either glue it to the socket or coat the outside with something tacky that'll make it stay in there, while keeping the inside dry and grease-free so it locks onto the plug for removal but comes off for reinstallation.

Think about it. Idle alone is 700rpm and if you dont keep it up its enough to stall an engine in first gear. You cant make that rpm or torque by hand.

What would this have to do with the engine or stalling? I'm talking about the trans when it's off the car. I was able to change gears with the input shaft stationary, and verified it by then turning the input shaft by hand and noting the direction and rate of movement of the output shaft. If this works when the input shaft is stationary then why wouldn't it work when it's being moved by hand?

In any case it doesn't really matter as it's not an essential thing one needs to do. Just curious.

Btw to use an old clutch disc to help with removing and torquing down the 36mm bolts, couldn't you also stick a pry bar into an opening in the disc and use some ridge in the bell housing to keep the disc from moving, or is that risk given that it's aluminum?

Alternately, couldn't you also stick a pry bar in there, with the handle at an angle on the ground or workbench, like the way you secure the flywheel when installing? This would be to avoid having to weld a tool hack together.

 

[AWD-Tony]

The idea is for it to NOT come off easy, though. It's supposed to stay on and grab the plug for removal while also staying in the socket AND come off the plug after reinstallation.

Only way I can see of that working is to either glue it to the socket or coat the outside with something tacky that'll make it stay in there, while keeping the inside dry and grease-free so it locks onto the plug for removal but comes off for reinstallation.

Omg dude. Try it and let me know if it doesn’t work. I’m speaking from experience. It will still hold the plug unless your rubber boot is loose in the socket.

@XC92

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[twicks69]

For the shaft nuts; for removal, unstake them using a straight blade 3/16" flat head screwdriver and hammer and clean any debris out of the slot with compressed air. Then shift into reverse and push the reverse synchro fully down and simply use a 1/2" cordless impact and 36mm socket and remove both shaft nuts.

For removal of the 5th intermediate gear, please use the proper tools. An OTC1122 splitter with OTC7393 push puller will remove the gear with ease and will not damage anything.

For shimming, it should be done in ROOM TEMPERATURE with an accurate micrometer and I use 0.062" diameter solder for the input shaft, intermediate shaft and front differential, and 3/32 (0.093" diameter solder for the output pinion shaft and center differential. 2x 3/4"-1" pieces evenly spaced away from the case slots, with the solder curved to fit the overall contour and place in the case sections using a generous amount of assembly lube (I mix petroleum jelly and 85w140 gear oil together with a drill and beater in a container, works excellent). Lube the bearing race OD's and gently install with the solder in place (you should not have any shims in place for this, only the solder). Lube the front differential roller bearing OD, lube all installed bearing race ID's and the tapered roller bearings. Install gear cluster case section and torque evenly to 29 ft/lbs. You don't need to have the case oil guides in place for the solder stuff, nor the shift rails or reverse idler components since you are taking it apart right after; just the front diff, output pinion shaft, input shaft, intermediate shaft. Then install center diff, install bearing plate the same way with solder in place and bearing races installed all lubed up. Place bearing plate on gear cluster case section and use a pick tool to make sure the solder doesn't pop out from under the races. Then install 5th gear cover and again, evenly hand tighten all the bolts and torque to 29 ft/lbs. Let sit for a bit, I'm normally 20-30 minutes. Then disassemble, remove bearing races, remove solder and measure. You should be seeing relatively accurate numbers within 0.001-0.003" of each piece per shaft and easily take the average of the solder pieces to have your ZERO VALUE. If you don't have confidence with your numbers, do it again. See below for the range of shim thicknesses made by Mitsubishi so you have a relatively quick idea of what range you should expect as a zero value. If you are seeing solder thicknesses near the high-end of the thickness range and you are using USED BEARINGS, you likely need to replace those bearings and redo the solder testing. To get your desired preload value, take the solder thickness and ADD the desired amount. To get your desired endplay value, take the solder thickness and SUBTRACT the desired amount.

For final assembly, RTV your bearing plate and main gear cluster case section using Permatex Ultra Black RTV in a thin / fully covered evenly coat. It doesn't have to be fully seated yet but it should be down enough to install the remaining components for final assembly. Install reverse light switch and gasket, shift rail detent balls, springs and detent plugs with a drop of Loctite 290 and hand-tighten plugs (you can torque them after the parts are installed and 5th cover is on and case bolts torqued).

For tightening of shaft nuts, install 5th intermediate gear first, align the output shaft detent with the center differential detent hole, install viscous coupler detent ball, and install viscous coupler the first section, then rotate and tap down until it is fully seated. You may need to place a prybar between the table and have the case elevated with a block of wood along the bellhousing by the front diff (not over the axle seal, do it along the transfer case mounting bolt hole area on the outside edge of case), then tap the coupler fully down while pressing up on the output shaft until you have the space needed to install the viscous coupler snapring. Then install the 5th input gear needle bearings lubricated up, 5th gear lubricated bearing bore and synchro cone area, then install 5th synchro lubed, align and install 5th/Rev hub and slider with reverse synchro and 5/R shift fork. Tap the hub and slider fully down making sure you don't have 5th synchro jammed and the keyways are aligned. Install input shaft side shaft nut, install 5/R shift fork roll pin (slot should be in a 6 or 12-o-clock position for all shift rail roll pins, NEVER put them in a 3 or 9-o-clock position as they will work themselves out over time with hard shifts). Then shift the transmission into reverse, again holding the reverse synchro down, and tighten the intermediate shaft nut by placing a hand on the viscous coupler and using your 1/2" impact on the shaft nut. You will then do the same for the input shaft nut. Then stake the shaft nuts. If you have a quality enough impact you won't need to use the modified clutch disk to hold the input shaft to torque the end shaft; it is also a royal pain in the butt to do this as you then have RTV smearing everywhere and it is a general hassle. RTV the bearing plate and 5th gear cover, install cover making sure the reverse wave spring is properly installed and seated on the reverse cone so it does not rotate past the tabs, then put some gear oil on top of the reverse synchro and in the input shaft oiling hole, then align the plastic oil guide with the 5th gear cover oil guide so you don't damage them and install 5th cover, then torque all fasteners.

5th cover and main case bolts are 29 ft/lbs, evenly, star pattern by hand then torque.
Reverse switch (with gasket), reverse lockout switch (with gasket), shift detent plugs (with loctite 290), and reverse idler shaft retainer bolt (with gasket) are all 22 ft/lbs.

Shim ranges:
Input Shaft / Front Diff: 0.017-0.059"
Intermediate Shaft: 0.031-0.058"
Center Diff: 0.044-0.070"
Output Pinion Shaft: 0.042-0.075"

As for available shims, there are many of them that are discontinued so you can only do so much nowadays, but if you can get the desired number by stacking them, that is fine too.

For OEM helical gearsets and stock bearing plates, I go around the following numbers that i have posted many times before:
Stock/Street Transmissions with less than 400TQ at the crank:

Input Shaft --> 0.004" - 0.007" PRELOAD
Intermediate Shaft --> 0.005" - 0.007" PRELOAD
Center Differential --> 0.005" - 0.007" PRELOAD
Output Shaft --> 0.003" - 0.005" PRELOAD
Front Differential --> 0.002" - .0067" ENDPLAY

Street/Strip Transmissions with less than 600TQ at the crank:

Input Shaft --> 0.005" - 0.007" PRELOAD
Intermediate Shaft --> 0.007" - 0.009" PRELOAD
Center Differential --> 0.005" - 0.007" PRELOAD
Output Shaft --> 0.003" - 0.005" PRELOAD
Front Differential --> 0.002" - .0067" ENDPLAY

All out RACE Transmissions that are Rebuilt/Inspected regularly with more than 600TQ at the crank:

Input Shaft --> 0.007" PRELOAD
Intermediate Shaft --> 0.008" - 0.010" PRELOAD
Center Differential --> 0.005" - 0.007" PRELOAD
Output Shaft --> 0.004" - 0.006" PRELOAD
Front Differential --> 0.002" - .0067" ENDPLAY

For Extremely HIGH HP/TQ transmissions (As in ~900-1000+TQ at the crank):

Input Shaft --> 0.007" PRELOAD
Intermediate Shaft --> 0.010" - 0.012" PRELOAD
Center Differential --> 0.005" - 0.007" PRELOAD
Output Shaft --> 0.004" - 0.006" PRELOAD
Front Differential --> 0.002" - .0067" ENDPLAY

 

[XC92]

Omg dude. Try it and let me know if it doesn’t work. I’m speaking from experience. It will still hold the plug unless your rubber boot is loose in the socket.

And that was my point, the boot IS loose in the socket and keeps coming off. I'm more interested in making sure it doesn't come loose than in it not sticking to the plug. If it's secure in the socket, it's coming off the plug--unless the extension then comes out of the socket, but that's a separate issue.

Here's the challenge:

1. Keep the boot secure inside the socket
2. Keep the boot attached to the plug when removing and installing, so it doesn't fall in
3. Allow the boot to detach from the plug after installing
4. Keep the extension in the socket when removing

These are in conflict with each other. Keeping the boot secure on the plug makes it more likely that the extension pops out. Loosening its grip on the plug makes it more likely that the plug falls in.

In any case I was just looking to solve #1.

...

Thanks, extremely useful. I'm going to allocate at least a month to this, not even including doing as much research and prep as possible before actually cracking open the case, to know exactly what needs to be done and how this all works, have all the right tools and materials I'll need, and allow for the time it takes to figure out what parts I need and order them and wait for them to arrive. I have another car to use as a DD so I won't mind the down time. I want to get this right, and will be methodical.

Btw, you really recommend an impact wrench to torque the 36mm's down? Mine's relatively modest, a cordless Craftsman 300ft-lb, but that's still way more than the recommended torque spec. Is using a proper torque wrench not necessary or a PITA because it's so hard to lock down the shaft? The only time I've used an impact to torque anything down is with a crankshaft pulley on a different car.

Also, you said that to get the 5th gear off a splitter and puller would work, but what about the rest of the stacks? Do some of them require a hydraulic press to get the gears and bearings off or back on, or are there pullers with long and strong enough bolts that can do the job with enough elbow grease or an impact, kind of how wheel bearing kits work? I have no place to store a press at present.

Oh, last thing. You recommend Ultra Black RTV. Why that and not Ultra Grey? Isn't this a high vibration application, which the grey is more suited for? Is grey ok if that's what I have, or should I really use black?

 

[twicks69]

I prefer Ultra Black RTV, I want some elasticity, not rigid like Ultra Grey. You can use Ultra Grey with no issues though. NEVER EVER use standard grey or black, it will cause issues with breaking down in contact with gear oil and then it clogs everything in the transmission.

Yes, I recommend the use of a quality 1/2" impact tool for installing the shaft nuts. If you want to check it with a torque wrench after, and have a clutch disk socket tool and another breaker bar go for it, but you are dicking around more than getting stuff done.

As for gear cluster disassembly, an OTC1123 bearing splitter and OTC1130 bearing splitter with plenty of press tools, and a minimum 12-ton press will do the job. You are wasting your time screwing around trying to use a larger 10-ton push puller with jaws and for the cost of it, you could have simply bought a press. If you are rebuilding other RWD transmissions and have the need for a large push puller with extension legs and jaw attachments, go for it. A 12-ton press is typically around $140. As for bearing and needle bearing sleeve installers, I have so many real press tools that it is easy for me, but for a regular person doing the work, stuff like straight and reducer fitting exhaust tube adapters work very well on the cheap.