I curerently have a 10 spline m465 transmission with a np 205. want to upgrade both to 32 spline with no coupler. Is it best to find a tranny and transfer case already 32 spline or has anyone tried the conversion if so what kind of luck did you have.

quick & dirty parts list:
- output(main) shaft for 465 ('81-91)
- 465/205 round adapter ('85-91)
- round pattern np205 ('85-91)

IMO, buy a complete setup and sell off yours.

Or find one of these mysterious shorty 32 spline outputs that ORD "might have" made, see if it will work with the stock adapter. x2 on what u2slow said, just find an 84/85 and up 4 spd K30 and gut it.

not sure what you mean by upgrade to 32 spline, as I don't think you're really gaining much.

According to Novak,
Spline Misunderstandings Clarified

"More splines are stronger"

Not necessarily. Larger shaft diameters are stronger, and larger shaft diameters usually require a higher quantity of splines. However, the automotive powertrain industries migrated to more splines on shafts due to their ease (speed, cost, etc.) of manufacture - smaller splines being able to be roll forged instead of the larger splines having to be machine cut.

A 32 spline output shaft vs. a 10 spline spline output shaft is probably only minutely stronger, and a decision of use here should be driven more by compatibility than perceived strength

Does the total length change as far as having to cut driveshafts etc.

I have broken several 10 splines and everyone I talk to says they went to 32 and have not had any trouble

A 32 spline output shaft vs. a 10 spline spline output shaft is probably only minutely stronger, and a decision of use here should be driven more by compatibility than perceived strength


That's nice, but the 10 spline setup does have its drawbacks. Have you ever parted a somewhat higher mile truck with a 10 spline 465/205 (or Rockwell, they used the same 10 spline setup if they were married)? The splines are usually very noticeably worn. The sleeve that came out of my '69 had the splines almost worn away

I have heard of people driving along and then POP! and they have no power to the wheels, and think it's the tranny only to find out the POS sleeve (or the mainshaft of the tranny) lost its splines and now just spins.

Upgrading to 32 spline gets you two advantages, 1 being less parts...the mainshaft of the tranny couples directly into the input gear of the transfer case, no sleeve to add slop to the equation. The 2nd would be, the shaft IS larger. Just look at them...what matters here isn't spline size, but the O.D. of the shaft at the bottoms of the splines (for want of more technical jargon), and it's definitely larger on 32 spline junk.

What may affect this are metallurgy, I don't know what the shafts and sleeves are made out of, and if it ever changed over the production run. But the 32 spline stuff is only at most 23 years old now, versus almost 40 for the 10 spline junk, so age may factor here too.

Total length does change. The 85+ 465/205 adapter is ~10" long.
http://u2slow.gotdns.org:81/tcase/adapters/sm465np205new.jpg

Or find one of these mysterious shorty 32 spline outputs that ORD "might have" made

Weren't those strictly for the SM465/203 application? (OTT has made those from 2wd shafts BTW).

Weren't those strictly for the SM465/203 application? (OTT has made those from 2wd shafts BTW).

Yes, I'm sure you remember a couple years ago when I was asking the same questions as xtreme872. I didn't even know about the shaft until MJ brought it up, I could not find any specs on here or anywhere online. It isn't on ORD's website, and I still don't know how long the stock 465/203 adapter is anyway...and even if it did work, I don't want to be the guinea pig dumping hundreds into totally tearing down my 465 and having my 205 machined for the larger bearing and input gear, which would probably run me at least another $150 by itself. I could have called ORD, but decided against the whole idea.

That is why my truck now has a New Process 542GL and a divorced NP201 between the frame rails...I am very much motivated by using what I have laying around and can find cheap. :laughing:

Weren't those strictly for the SM465/203 application? (OTT has made those from 2wd shafts BTW).

I had Ott re work my 2wdr shaft to 32spline, no more sloppy 10 spline and hopfully it is stronger

I had Ott re work my 2wdr shaft to 32spline, no more sloppy 10 spline and hopfully it is stronger

Yours was the one I was thinking of. :D