Need some info from you Chevy guys on the differences in the 420 & 465 as far as spline count and length of the front shaft and bolt pattern on the tranny.Which would be a better option to put in a Jeep YJ?

T18. Leave the Chevy parts alone :p

Seriously, the 465 is a lot more plentiful and cheaper. Advance has what you need to do the swap, so does Novak's

I have a four banger and havent been able to find a bellhousing or adapter for either swap. I have found a 420 using a s10 bellhousing though,that is why I was wondering about the differences.I can get a sm 420 for like $25 and probably get a sm 465 for free if I take it out

Use the 465 and send me the 420. I don't have one of those yet....
:cool:

BEGONE JEEP BOY :flipoff2:

You'll like the 420 better in your jeep. Lighter, smaller, lower gear.
-- Mike

compare the dollars involved in a 420 vs a 465 and you will really like the 465.
only jeepers would like a 420:smokin:

Yeah plus he is going to send me the 420 :D

Advance says they dont make anything for it and Novak is working on it,the only thing Advance sells is for the nv4500.

so what exactly are you looking for?
what engine?
transfer case?

Trying to put an SM465 between a 2.5 four and an NP231 in a Jeep YJ.

ok, that makes it hard
but if you would change the TC you would have less trouble.
241s bolt onto late 465s
what is the 231 spline count that you have?

Just so happens I just did the same thing! I used a SM420, with a Novak adapter and new mainshaft to the NP231, the guys at Novak were great, they are working on the same swap for one of their rigs. I used a 2.8 V6 bellhousing out of a S-10 Blazer with a T-5, bolted right up! I had to switch to a gear reduction starter without a nose cone because of starter pocket issues, and I had to cut out the part of my old AX-5 bellhousing that held the flywheel position sensor. I ground / milled down the cut out section of bellhousing to bolt up to my S-10 bellhousing and only cut a small "window" in the S-10 bellhousing. The only thing I wish I would have done different was obtaining the SM420, I bought one that was laying out back of a trans shop for a 30 pack of beer and threw some new brass and bearings in it, now it jumps out of 2nd gear, so I'm looking at another one to transfer all the new parts into.

curious what that swap cost you?

Well, let's see, adapter and mainshaft from Novak - $600 , SM 420 trans - 30pk Millwakee's Best, bellhousing - free, but I had to take it out (PITA), clutch hydralic line (braided stainless) to go from silly Jeep roll pin fitting on master cylinder to regular brake fitting on Chevy slave - $30, new dual friction 9-1/2" clutch disk with Chevy 1-1/4" 14 spline hub - $150, 23 spline input gear for NP231 - $80, lengthen rear driveshaft - $60, having a 103:1 fist gear with a stock t-case - priceless, actually, under $1000, but these figures are all from memory, all my receipts are at home.

what 231 has that input?

Jeep 231's from a 6cyl will have a 23 spline input, 4cyl's run a 21 spline, so I had to swap it.

Thanks for the info, I'm going to go pick up a SM465 in the morning and see how that works out.:D Free trannies are great, really makes $1500 for an nv4500 seem a little pricey,thats a lot of :beer: money!!!!