I am building a Ford 300 to put in my 404 and I am deciding the best way to mate to the transmission. Has anyone had the input shaft out (and do they have pictures).

I am thinking about shortening it, al lot. but I haven't really made any firm decisions yet.

If someone had teardown pics of the transmission that would greatly aid my planning.

When I did my conversion I removed the Input shaft while the Trans was still in the chassis. If I remember right you cant just undo the front bearing retainer and pull it out like some transmissions because of the front gear on the intermediate shaft is in the way(part#109).

So I removed the front main shaft bearing retainer(part#330) and the rear torque tube and loosened the rear bearing retainer (believe its part#199) and barely had enough room to slide the input out over the gear. Hope that makes sense.

I Shortened the input 2 1/2" (wished I would have done more now)and had it re-splined to a 1 1/8"-10 spline shaft by Dutchman up in Portland. They had to have it unheatreated and reheatreated $$$.

Here's a link to the 6-8speed conversion I did.
http://www.rockymountainmoggers.com/temp/ModificationoftheUG1_0.pdf

You wouldn't perchance remember what the OD of the input shaft is would you? I would like to adapt it to take one of those quick couplers like many racers use between their transmissions and their t-cases.

If I remember right the OD was close to 1 1/4"-10 spline and it necked down after the splines but was still bigger then 1 1/8" that I went too.

I'm not sure you can put a coupler like that on the input shaft without getting a lot of clutch chatter.

Actually I was thinking about interposing an automatic transmission and using the mog tranny as a transfer case.

Actually I was thinking about interposing an automatic transmission and using the mog tranny as a transfer case.

This has been done at least once. a chevy V6 and corresponding auto was hacked into a 404 in front of the mog tranny many years ago. It was a local truck and has recently been sold to a mog repair shop in denver. It is an orange Doka.

It seemed to work fine minus some booty fab. The Engine also stuck out the hood.

I kinda figured as much.

I am anti bootyfab so I think I can make it work without that 'feature'. I was planning on removing the tail housing and using a shorty output shaft. I am thinking to use a 42rle so I can have overdrive. Without the tailhousing that tranny is surprisingly short. Not quite 2 speed powerglide short but still pretty short. Also the Ford motor is two inches shorter from crankshaft to top of valve cover than the mog motor and I have a 3 inch body lift so I should be able to fit it. Not sure about the radiator though... I will need to take a few measurements to determine if I would need to relocated the mog tranny more rearward. I am hoping not for all the obvious reasons.

On a side note, I believe the torque tube from the front will bolt up in the rear and vice versa. I also understand that the 404 came in a few different wheelbases. Does anybody have a list of the common torque tube lengths?

On a side note, I believe the torque tube from the front will bolt up in the rear and vice versa. I also understand that the 404 came in a few different wheelbases. Does anybody have a list of the common torque tube lengths?

yeah, this idea has haunted me for years. It will work fine, but keeping the cab closer to factory is hard without big cab lifts etc. So I have been thinking buggy chassis ontop of mog frame.

I needed to lift my cab to clear my tires anyway and the floor of my cab was already pretty Effed so I figure I will build what I want. The way I see it the 404 soft tops are really common so I don't think I am really committing any automotive sacrilege. The defining characteristic, I think, is really the nose so as long as I keep that the rest is stylistically immaterial as long as I keep it simple. At some point in the future I will likely close the gap in the front created by the cab lift with a custom bumper.

If I shift the transmission back everything else becomes much simpler. Engine placement, cooling system, etc...
but shifting it back presents it's own set of problems like having to source different torque tubes or modify mine and manufacturing custom linkages, etc...
It had also occurred that I might be able to cheat the cab forward if I only need a couple inches.

This one time in Vegas...

This one time in Vegas...

Is it story time?

Actually I was thinking about interposing an automatic transmission and using the mog tranny as a transfer case.

I am planing on doing a similar 404, I am going to use a very short modified input shaft splined to recive a stander yoke, then just a standard 1310 u-joint cupled to a slip yoke on the automatic. I plan to keep the transmission intact for more gear optons like yourself.

Oh I have something for ya then:
http://obelixen.dk/projekt%20r%C3%A6ser/
Scroll through the pictures and you will notice that he now has the front and rear torquetube swapped. Also he has a Rover (buick) V8 with torqueflite 3-speed auto connected to it. It is a mate of mine, and I have been along on all the building of the transmission, so if you have any questions, just shoot!

Some sad news; I just sold my Mog404, so I'm now mog-less, but happy to aid the community ;)

That's a lot like what I had in mind.

Did he lose reverse and low-range in the UG1/11?

I bet that mog frame has the fastest reverse ever.

I really like his high steer arms and his disc brake conversion. I am a little concerned that his rear u-joint is going to wear prematurely running at that angle but I really don't know... ya know?

Yes he lost low range and reverse, and something tells me even third gear as well? Not sure though. But he only uses the automatic when he wheels it, the mog gears are quite unnecessary, but nice to have if he ever wants to go fast ;) Well the high steer arms works very well, he made 'em himself. But the disc brake conversion is cr*p and bought from a now late english company. Not worth the material that was wasted on them IMO.
Re u-joint he has a limit strap (chain) which seems to work well enough, but that said he rarely wheels it, so not that well tested yet. But when I had my Mog lifted I had some vibrations from the front u-joint, drove it like that for about 6-7 months without any failures. BUT surely not ideal.

Thanks for posting, thats not exactly how I have it planed out, but still very helpfull, is you freind making those adapter for selling?

Heres how I am going to do it once I have the time and space:

#1 I will shorten the input shaft spline for 1310 yoke

#2 move mog transmission back 8"

#3 cut 8" out of the back torque tube

#4 add 8" to the front torque tube

#5 Engine and auto trans still undecided (more than likely a Jeep 4.6 stroker and Torque Flite 999) as I have them laying around already.

Can you post some pictures of your old Unimog 404 with the lift, that would be cool also!

I've been doing a bunch of research on this again and have come to the conclusion that I'm always going to be limited with the mog transmission. My biggest problem has always been the fact of no overdrive. Did some research into installing a Advance adapter Ranger overdrive between the motor and trans basically making a pre transmission doubler. But after talking with a person who had one in a FJ I decided against it for the mog.

There were two issues I came up with,
One the guy said it was harder to shift the factory fj trans he believed it was due to the extra rotating mass and worn out syncro's. (like my trans) He rebuilt the trans and the issue almost completely disappeared. Shifts then became sluggish. The other was the fact that there's not alot of info out there on the actual power a 404 trans can take. Too under-drive or overdrive with some sorta transmission (torque multiplier) before it cant be good especially for my beat on trans. So I would have the cost of a new trans, the Ranger box, and machining of the mog input again. Just to have a trans that I still wouldn't be confident in.

I even looked into possibly swapping in other Unimog trans and almost went the 20speed 406 route. It was looking promising till a buddy asked me why I just don't go the domestic route. My reply to that was I really didn't want to four link it and that I felt the torque tubes are what makes it a Unimog. So I starting searching a around a little differently and came upon these 2 threads where Domestic transfer-cases are mated to torque tubes.


http://www.pirate4x4.com/forum/showthread.php?t=89095
http://www.pirate4x4.com/forum/showthread.php?t=804177&page=3

Which leads me to what My current plans are. I'm planning on ditching the mog trans all together and going with a NV4500 too an atlas 4speed. All ready have the nv4500 and the Atlas is on the way to late now.
Rough measurements for me are a 5" longer front drive and a 12" shorter rear, going to try and move the engine back 2" also. Planning on building a completely new engine cradle to encapsulate the atlas and take the suspension force's along with allowing frame flex and the ability to drop the whole engine, trans, and transfer out of the chassis from the bottom. That is after pulling the front axle.

This combination will give me a 20 speed system and a nice shifting trans with a .73:1 overdrive and a 5.61 first gear. Not to mention the possibility of dropping a 100lbs. Still working things out, not planning on doing the swap till the end of the summer, hopefully my current trans holds till then.

Just a little food for thought.

On my lid, I agree with a few thing you are saying, some not so much. I will be keeping the mog trans for a few reasons.

#1 Mog trans is not to weak (when not shifting to much like in snow wheeling or in traffic), I also have a 406 with wide 46's beadlocks and a turned up desile IP with bunch of other little things, I drive that unimog not to often but when I do I drive it like I stole it lol (like your self lol) hard shifts high revs. I find it fun to push my unimog to its limit passing other cars on the highway lol.

#2 404 trans is weeker than 406 like you said, the bushings cause problems for shure, but... over filling the unit with good GL4 helps alot. The main damage come from over reving, lack a lube, and hard shifts, like when breaking snow lol.

#3 the Auto trans acts like a buffer reducing shockloads, instead of shiftng the unimog transmission constantly, you put it in a selected range on road 6th 1:1, or a lower gear for better offroad 1st 2nd 3rd or 4th gear

#4 An auto trans can also provide an over drive like a AW-4 0.69:1

#5 It is way cheaper than modifiying a 205 or other t-case, you get more gear reducton and you get a no hasle over drive.

#6 Wolfgang and others have built unimog t-cases using the t-case portion of an original unimog transmission (just another option)

Every UG1/11 failure I have ever read about has been related to extended high RPMS and or using the wrong gear oil. I am sure someone has broken one with too much power but I have never heard about it.

Also if MB is providing a granny gearset (the crawler gears) more than trippling the torque passing through the geartrain, then they cant be that fragile. Ironically I understand that the crawler gearset IS pretty fragile but not the OE tranny internals.

The way I see it, interposing an auto should be no worse for the tranny than adding the crawler gears and in some was it will be easier on the gears as the torque converter should normalize loading.

Snow Mog I agree with some of the stuff your saying also. I had looked into putting an auto like an AOD or E40D in, trust me I would love an auto as buffer would be nice. But I'm already having problems with my current trans holding up after less than a year behind my 350hp + V8. Been running Synthetic fluids and even stop and let the trans cool after hard pulls. Even looked at putting an oil pump in for cooling the trans and using it for a positive pressure oiling instead of splash gravity feed like they are stock.

To take a transmission like an AW-4 and under-drive it, first gear 2.8:1 second gear 1.5:1 thus multiplying the engines power going into the moggs tranny. Do you think that the 404 trans is still going to hold up? There strong but what is the torque capacity of the UG1 or UG2 transmissions, Sure third is 1:1 which won't make a difference and fourth being overdrive will help.

Since most people looking for an overdrive option have already or are upgrading to more powerful engines This just compounds the problem even more. Not to mention the added weight, length and chassis flex control.

For me I feel that ditching the stock 404 trans that you can't beef up at all, in favor of a trans that has a known torque rating of 460 ft-lbs stock and can be modified for more relative cheap is the way to go. Yes bolting the torque tube up is going to take a little machining. Once I'm done with that I'm free of all the little problems associated with the factory transmission. Like bad bushings, overheating, no overdrive, Limitations of the ujoints binding before full droop, Shift levers strung out everywhere, etc.

What I'm planning might not be good for everybody but I believe its the best and cleanest option for me.

The funny thing about the 404 transmission is that when you look at the gears and shafts everything is HUGE, and by no means do I believe the materiel used is bad, or unsuited for the task. So what makes it all go pear-shaped for so many people when upping the power? I'm convinced the only two problems are the bearings not being roller or ball type, and heat. And I too think that solving these problems would be my preferred solution. But OML I'm intrigued to know what exactly is dying inside your tranny?

Plane bearings are some of the strongest and best wearing. Take for example your crank shaft. I think the trick would be to add a positive pressure oiling system. It also occurs that one could build a water-cooled pan like they now make for the two-speed powerglide. Of course this is really only an option if you don't have the crawler box.

Like I said earlier, in my 406 I over fill the trans +2 liters (also use Luces oil slickshift additives with a good GL4) this has made it run cooler shift smoother, and more than likley is saving wear and tear on other components clutch, u-joints, axles...

S.frimodt I looked up your old 404 with the big tires, just wanted to say nice rig. too bad you sold it why?

My major issues have all been around the counter shaft with the worst happening back in June. I was on a recently logged 45 to 50 degree slope with big holes and logs, making a new trail. (This was Private Land!) Bounced the rev limiter a couple of times when in 2Low went too 3Low to finish the climb. Transmission temps that trip never got above 150 degree Fahrenheit. On a scale of 1-10 on how hard I abused it that night I would say about a 5 defiantly not the hardest. Leaving later that night went into high range and 2high and 3high were howling. Limped it home in 4high about 5 miles, pulled the pan the next day to find that the Front Counter-shaft bearing was shot. Scoped the bearings and gears didn't see any other problems.:shaking:

Because of how I built my adapter I was able to install a new bearing which brought the counter-shaft end play back within factory specs without having to pull the trans. Took for test drive 2high barely hear any whine or howl but 3high is still there but not nearly as bad. Since then I have drooped the pan again only to find that gears 55 and 47 in the exploded picture had sustained some severe wear pattern issues.

Whether its the power, temp, rpm or shock thats caused these issues its hard for me to be confident what exactly caused it after all its a 51year old vehicle. With no history of use before I got it. That night temp wasn't and issue but who knows what previous damage due to the heat had on the failed components. The trans has seen temps as high as 210 (gear oil starts breaking down around 220) At this point the transmission has had more oil changes then the new motor with an extra quart plus left over added every time. That is fill to line, finish that quart and add one, usually 1 1/3quarts total extra.

Before when I was planning on keeping the factory trans I had started some modifications to add an oil cooler. Currently the trans has been tapped for a feed and return line for an oil cooler. My plan was to run a 135 degree thermostatic controlled electric high temperature gear-oil pump into a filter through a oil cooler then into a manifold system with flow controls for different oil delivery ports. As you can see the counter-shaft in the picture oil flows down the center of the shaft feeding the venerable plain bearings #52, 45 and 19 in the exploded view. Yes plain bearings can be some of the strongest and wear resistant when properly lubed. The front counter-shaft/speedo/bearing retainer, has a gravity feed port is in its casting for the front counter-shaft. The plan was to tap into that port in such a fashion that I could force oil down the counter shaft and still retain the gravity aspect for when the oils temp is below 135 degrees. Thats about as far as I got with figuring out possible oiling upgrades. I know these are a few of the bearings that have issues but Im not positive there the only ones. Thats about as far as I got with figuring out possible oiling upgrades.

I have heard that someone had replaced these bearings with needle bearings but I don't know much more then it wasn't cheap.