sm465 to nv4500 swap - parts interchangeability, modifications, etc? (1 Viewer)

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Did a search and found a lot of folks debating the merits of the sm465 vs nv4500 and even talking about swapping, but no real details about what parts would interchange and what modifications would be needed.

I currently have a sm465 behind a mild 350 and experiencing the common 3rd gear failure. I considered rebuilding it, but given my location in NJ, I do a lot of highway driving to get to any sort of trail and an overdrive would be a welcome addition. I'm not doing any real crawling with this rig and any off roading is limited to things like fire roads, camping trails, and light trails in the Pine Barrens. I'd love to do a smooth shifting nv3500 swap but AA doesn't make a transfer case adapter so I'd be limited to adapting a dana 300 and doing the mini truck centered rear axle housing swap. Not sure that's a can of worms i want to open at this point, so leaning towards nv4500.

I'd love to hear from folks who have done this swap as to what I might expect to encounter (moving crossmember? parts interchangeability such as clutch, transfer case adapter, etc?)

my current setup is utilizing an advance adapters bellhousing, 3 speed transfer case adapter, and crossmember. I understand I'll likely have to get a new AA bellhousing as the nv4500 pattern is wider unless i use the stock bellhousing with the internal slave. I'm not sure if the transfer case adapter can be reused and am waiting on AA to respond to my inquiry. In the meantime, i figured I'd post here and see what info I can glean.

and also, no, a h55 and split transfer case swap is not really in the cards. Too $$ and impossible to find around here.

Thanks!
 
Think about it this way; you start with your V-8 (hopefully positioned per the Downey installation instructions) and transfer case. Everything in between gets replaced with the pieces of your desired configuration. Pretty much the same when you swapped in the SM465.

I didn't have the SM465 but swapped out the factory 3 spd for a NV4500 instead on my already V-8 powered FJ-40. I didn't have to move the rear cross member for my conversion but did have to snake in the transfer case. Get the driveshafts adjusted as needed and you should be good to go. I went with factory bell housing and internal slave, AA adapter between trans and transfer case. You'll probably have to re-configure the shifter hole locations in the trans tunnel as well.

I almost forgot, depending on the condition of your flywheel, clutch and pressure plate they may need to be resurfaced. If I remember correctly you will need a new clutch disc to match the NV4500 input shaft as well as replace the pilot bearing with an extended version.
 
thanks for all the info guys. Looks like it'll be $2k for this swap + a buttload of my time and energy. With the sm465, I'm usually around 2800 rpm on the highway which isn't the worst - however, the gear spread, dump truck shifting, and 3rd gear issues have me wanting better. But it appears, my wallet might not support my wants here.

Last i had it open, the syncros seemed fine but 3-4 shift fork teflon coating was pretty worn. Might pop the top again and replace the shift forks and see if that helps.
 
Could you refresh me on the "3rd gear issue"?

3rd gear popping out and grinding. Several *fixes depending on the cause - could be the 3/4 shifter fork plastic coating having worn preventing it from engaging fully, 3rd gear countergear snap ring breaking, worn synchros, etc.
 
Here is some additional info that may help.

I didn't have to move the rear frame cross member, only the rear Downey transfer case mount frame location.
 
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