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Sorry to correct my friend Goldhammer, however ...

The Dana 300 has an iron case. The output housing is aluminum, and an easy distinction compared to the similar appearance Dana 20. Many (most?) Jeep D300s (later CJs and all YJs?) came with a slip yoke, and the SYE (slip yoke eliminator) is a popular upgrade.

Only one year of Scouts - 1980 - had the Texas pattern Dana 300. And the input splines are different between the automatic and manual versions. The manual version is highly sought after. I expect no more than a few thousand ever existed. I have seen 1980 Scouts with the Dana 20, where someone has bought the vehicle, taken the D300, and resold with a 20. All other IHC years got the NP circular pattern.

Realize that the conversion parts for a Dana 20 to a 700R4 or whatever are going to be more than $500. You should be able to source a compartible NP transfer case for that much. And the transmission will have to completely come apart to receive a new D20-compatible tail shaft. It's the very last thing to come out.

Apparently the D20 breaks output housings in severe use. You can fit an aftermarket housing for another several hundred dollars, or carry a spare. Look on Pirate for the "Uber 20" thread.

JM0 - you want a complete Chevy/GMC donor that's 4WD with a NP241C and 700R4 or whatever. Seek the right donor vehicle.

Thanks Tim, I stand corrected. Memory not what it used to be.
You're right in trying to source a married package deal. Don't know when his transmission choice came out, but most everything from around '88, except Suburban and Blazer, (up to the body style change) will be a driver drop.

I seem to remember that 20 cases tend to break housings across the pan opening under hard use. Old trick was to use 1/4 inch steel plate, make a gasket shape ring and install between the case and pan.

Ok, that sounds like a great idea Tim. I'll try and source the transmission and transfer case that way. Too bad I can't get the axles from the same vehicle!

Also, I guess the next piece will be a lift. I have read a lot of reviews on more modern SJs, but have found very little on the 63-65. Any recommendations there?

Also, I guess the next piece will be a lift. I have read a lot of reviews on more modern SJs, but have found very little on the 63-65. Any recommendations there?

In '73 the front suspension changed from post-mount spring-over to "conventional" spring-under. You can see pictures of this in the '62-73 J-series parts catalog on the Tom Collins site. Realize that your later front axle will be spring-under and either the axle or the suspension will need to be changed to match.

In 1975 (?) the rear suspension design changed from "post mount" to whatever you would call it - box mount? Your later axle should bolt to the factory springs if you keep that design.

Very few suspension options for the pre-'75 Wagoneers. Hell Creek has a package on their hard-to-navigate site. Dayton may make factory replacements. A spring shop like Deaver or Alcan can build whatever springs you want for $$$.

If you find an axle donor, you could take the whole rolling chassis and build on that, then adapt your early body and accessories to the later chassis. This would solve your suspension issue if the chassis '75 or later. Likely there will be changes needed for the mounts etc. but I don't know the details. Realiize the VIN is carried along with the chassis and you'd need to ignore that or remedy with the DMV somehow.

300 has an aluminum speedometer housing, case is cast iron, IMO not much stronger than a 20. Unless you are really beating on it in low range, a 20 is more adequate but with LS power needs an output upgrade, Novak and a few others sell them and are very easy to install. The bigger issue with a 300 or a 20 is transmission clearance for the front driveshaft. There is a reason the automatic/dana20/dana300 combos have a 1-1/4" diameter front driveshaft, the clearance is very tight. Not as issue for light to moderate use, but heavy use or lockers will necessitate a larger front drive shaft, making the D20 or D300 a poor choice. Just my opinions developed from years of building and observation.

Certainly the chain-driven transfer case allows more clearance for the transmission than the geared cases like the D20 or D300. Chain-driven is also much quieter than the gear-driven cases, which matters quite a lot in these upscale vehicles. Higher GVWR and more power to compensate for higher curb weight suggests a stronger component too. A D20 is typically fine in a CJ, even with large tires.

Also mention that tires today are on average MUCH larger than what was used in the day. More inertia (angular momentum), more traction, larger frontal area add to power demand and drivetrain stress. A '64 Wagoneer with factory-sized tires will be fine with a Dana 20, IMO - and will go a surprising number of places.

The CJ guys like the D300 for its superior reduction and compatible overall length and width. In a CJ-5, you must fight for every additional inch of rear driveshaft length. A D300 combined with a truck 4-speed and a deep but streetable axle ratio, you can approach a 100:1 crawl ratio without any heroic changes or huge expense.

I love the 64, Good luck with your build.

I went a little heavy handed with my build, still running stock brakes and my last trip down hill was 8000 foot elevation change in about an hour and half. Didn't have any problems. I did change master cylinder but that was mostly for clearance of clutch master install.

My old power assist steering was antiquated so I installed power box up front, this requires moving cross member.

I was able to fit 33" on 15 x 10 but my fenders are cut.

I used yj (I think) rear springs up front with longer relocated shackles, and rear shackles flipped with 2.5"
Blocks in the back and longer shocks and brake lines all around. I really really enjoy this setup, fairly inexpensive and simple with great ride quality.

Hope your turns out nicer than mine.

https://www.fsjnetwork.com/forum/downlo ... hp?id=7629


The springs I used up front are
rubicon express 1430 49786
I believe it's a 2.5" lift spring for yj rear.

Thank you 230ohc. Awesome 64. It's great to find out that I'm not the only one crazy enough to want to drive one. Thanks for the details as well.

I have finally gotten the parts and pieces I need to get this project underway. Currently rebuilding the Dana 44s front and rear. Short block is on its way, freight. Looking forward to getting my hands dirty.

I just cut the stock suspension off and mounted what I wanted on my 64. As said before, it is really more like a hot-rod type of a build than a restoration once you go down the rabbit hole. It is just easier to swap stuff out than to try and make small changes work with the early parts.