Manual Transmission Spline Gear and Identification assistance.

[forgeman]

Hey Gang!

I'm in progress of a complete over haul project on a 72' C20 2WD. I've pulled the engine and transmission. Once the transmission was separated from the engine I inspected the spline input gear and noticed that there are "issues". There are hairline cracks on the input spline along with the spline is starting to "corkscrew" ever so slightly. (See Figure 1)

Questions:
Does anyone have a good resource for a replacement spline input?
Is it worth it to tear down and fix or should I search for new?
Can anyone identify this transmission (See Figure 2 for top plate numbers, Figure 3 for bottom plate, Figure 4 is total transmission)?

Thanks for any assistance!!!


Figure 1:


Figure 2:


Figure 3:


Figure 4:



Overall project images (some better overall pictures of the transmission too):
http://picasaweb.google.com/forgeman

[kwmech]

4speed manual trans ----SM 465


nice twist on the input

[WorkinLonghorn]

The 465s had PTO covers on both sides.I think that is a NP435.
If it is,I can't imagine how that shaft was distorted like that as those units were very stout. Must have been some serious abuse to cause that. I would open it up and have a look but You might be better off getting a junkyard piece and build one using the good parts from each.They make a "rebuild" kit for those which includes bearings,bushings,syncros,seals etc.If you have,or can get a few tools for this kind of work I'd fix it myself with the kit and a second unit for parts.

[forgeman]

The "abuse" was a ring and pinion gear in the rear end shattering while going down the highway.

Never have I been so scared!

Thanks again for the Identification help!!!

Also, for anyone else who is looking for identification / rebuilds I found these two pages quickly after I had the hints posted from above.

I agree with the first reply (SM465), It does have the PTO cover plates (sorry the pictures are from the wrong angles) and the NP435 lacks the "ribs"

NP435:
http://www.novak-adapt.com/knowledge/np435.htm

SM465:
http://www.novak-adapt.com/catalog/sm465_parts.htm


And a really great side by side (scroll to the bottom):
http://www.novak-adapt.com/catalog/t...n_packages.htm

[WorkinLonghorn]

I stand corrected! Anyway here's a place that has your 465s for $795 but I have never dealt with them.

[forgeman]

Again thanks to all for the help!

More info on the SM465. (And pictures)

Here is how the gear shift lever goes in! (No drills necessary!)



Second the transmission with the top of the housing removed. I'm AMAZED that the gears / syncros / bearings are all still perfect. These transmissions are amazing.



Hope this helps future SM465 re-builders!

More pictures on the way. I've purchased a "junk" core from craigslist to replace the input spline gear. The junker is a classic case of an owner who didn't know how to drive a manual and played the "can't find it grind it" game. The brass syncros are a mess yet, the primary gears are still "pretty". I highly suggest this transmission!

An example of what can't find em grind em does to a brass syncro:



Just take a guess of the syncro that came out of my transmission (corkscrewed) and the one that they ground the gears to shreds and placed the core on craigslist.org. (hint mine is on the left).