My 66 Unimog 404 Cartography Truck

I got the parts through a seller on ebay "nos4jeeps" I paid $370 for all the parts shipped from turkey. Way cheaper then Scott, but had a long lead time...

Has anyone adapted an external transmission cooler/pump on the 404 transmission?
My seller had an identical experience with a transmission failure in the other 404 I was going to buy; he was going downhill on a long steep grade and it locked up.
What is the "safe" temp range should I be running the trans at?

I also need tires, I can pickup some 11.00-20 Michelin XL's in a couple weeks. What are you running on your mog? looks like 11x20 NDT correct?
External coolers have been fitted to 404 transmissions, but its added complexity for less than a huge gain. Temps with GL-4 should be around 230, definitely keep it under 250. The Amsoil synthetic claims to provide protection to 300 degrees, by which point a conventional would totally break down. The transmission is splash and capillary lubricated, and I believe the thin synthetic does a better job making it through the smaller passages while still providing sufficient lubrication. Make sure not to use a GL-5 oil in the transmission, as it may corrode the yellow metal plain bearings and be too slick for good synchro operation. GL-5 is fine for the diffs and hubs. Make sure your diffs aren't overfilled, as its a sign of leaky transmission output shaft seals.

I'm running 9.00x20 NDCC's, which are actually a few inches larger in rolling diameter than the stock 10.5x20's. "X.XX" indicates a 100% aspect ratio, vs "X.X" indicating 80%. The previous owner had fitted 11.00's thinking they would be only slightly bigger than stock, but a new 11.00 measures almost 44", 7" bigger than stock and enough to cause rubbing front and rear offroad and preclude use of 6th gear on level ground, limiting top speed to about 45mph. The 9.00's are relatively cheap and plentiful, and work amazingly well considering their narrow width.
Thanks for the tire info, I may be stopping by 100dollarman's place when I go to the hammers next week and get some!
I did finally get to work on it; I was about to remove the master cyl and I noticed the rubber boot on it looked brand new, so I decided to try re-bleeding the system.
To my surprise, I got the brake system to work, there was lots of air, but a nice firm pedal now and no apparent leaks.
I next turned my attention to the fuel system, no gas left in the tanks but there was some varnish. I removed the fuel tanks and took a look inside, and they are both rusty! the crossover rubber tube was also completely derioriated. Suction pickup tubes were also rusty halfway up, and the strainers look ruined.

I never have cleaned a fuel tank before, so I figure this should be good experience. I think I will try the chain in tank trick, and I ordered two quarts of Red-Kote.
It was a bit rainy out this past week too, had to protect the cab with the canvas deteriorated.
I got my tires from Hundy too, he sent me to a shop a town over where the guys mounted them by hand for $40 each. They probably know better now.
No tires yet )-: everyone was at the hammers!
I got the tanks cleaned and red-koted


And I do not have a battery tray!
So I drew this up and I am going to cut it out Friday, it uses a ratchet strap to keep them in place.
Here it is cut out, I got it scratched up already:) moving those batteries around was a PITA. I made it out of 3/16" it's pretty heavy lol

Tight fit in there, took alot of measuring to get everything secure and clear the terminals

Then I turned off the disconnect and she lit up for the first time!

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First I disconnected the coil, pulled the plugs, cleaned them up and squirted PB blaster Lawn Mower Tune up into the cyls to free up any rings or valves that could have been stuck.

I let it sit for an hr then I bumped it and it turned over instantly!
I brushed on some anti seize on the plugs, re-installed them and the coil. Then spend the rest of weekend flushing the fuel system,and I got it running! I am impressed at how quiet it is!
It runs!
Also picked up some used 9.00 x 20 NDT's for $50 each, taken off a m35a2 date code 2009
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So I needed new tank seals since my old ones were shot and I don't agree with paying $9.08 for each one from expedition imports, so I modeled them with the interesting bolt pattern and cut them from a strip of nitrile rubber. Electricity, garnet and other factors considered I paid ~18 cents each:)

On the waterjet brick

The complete gaskets

And the Waterjet in action
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Nice to see your excitement at such a young age.

I almost bought the larger big brother of your 404. I don,t remember what the model was but it was in excellent condition, it had 4 doors and a ready nice expedition camper on the back. $27,000.00 US dollars and my older brother talked me out of because he said where ever I went in my home town everyone would know it was me because you just don,t see these vehicles in America, at least not 10 years ago.i have to say I regret not buying that rig because it was very nice and I know there built like tanks! I,m going to own one someday but I,ll have to save for awhile before I can afford what I want. Good luck with you restoration of a great vehicle . Steve
I Pulled the engine forward and upward last weekend, what a PITA it was horrible. I had to remove almost everything (hoses, windsheild, floor pans, exhaust, wiring,starter, hood, radiator, fan, pulleys, air compressor, oil filter holder, heat riser system... and much more misc crap) and fight the worst rusty bolts ever known to man.

I was greeted with a exploded clutch, one of the arms on the pressure plate looks like it's gonna fall off so I spent half a grand to get all new parts, the spacer ring got lathed by the clutch but it shouldn't effect the operation.

New and old pressure plate

flywheel had some surface cracks and gouges so I got it resurfaced.

should have it all back together this weekend!