NP241 Teardown and Reassembly, Input Shaft Replacement

The teardown and reassembly of an NP241C from a '90 Suburban. I tore this passenger drop case down to install a 27 spline input from a newer driver drop case to allow me to mate it to my 4L60E as installed in my '87 Blazer

[@John-do3sx]

Thank you for actually showing how to do the reassemble!!

[@carlosrendo4970]

Sweet job dude!

[@yuetoobseabass]

Thanks for posting this!

[@genepatrick]

I'm planning on doing the same LS swap with my 95 Tahoe I was wondering if you can do a video review of your truck and some of the things that you had done and how you solved some of the challenges you ran across

[@richardnewman1856]

My input didn’t come with the two pilot hearings inside it for the main shaft. Maybe yours did or maybe you left them out.

[@michaelbrogdon9676]

Thanks for the video, very helpful. Im wondering if I am going to have to do the same. I have a 94 silverado collecting parts for a gm dana 60 solid axle swap. It has a 4L60E in it as well. For my passenger drop tcase I am picking up an NP241 out of a 91 suburban. Will I need to do the same to get the passenger 241 to bolt to my 4l60e? thanks-Mike

[@bman222112]

No, you shouldn't, at least as long as the suburban it comes out of has an automatic transmission. If it's off of a manual transmission, then it will have the 32 spline input shaft like mine did, otherwise it should just bolt right on.

[@VQ1whales]

What order did the plastic and metal thrust washers go into the planetary gear?

[@bman222112]

It's been a few years since I tore mine apart, but looking at parts diagrams, looks to me like there is a thrust washer both below and on top of the input gear, and then the retaining ring on top of the thrust washer before the snap ring.

[@rodriguezluisu87]

Im the other way around! Im swapping a NV3500 from a 95 truck on my 2000 tahoe with 4L60E with NP246 tcase. My question is can i swap the input shaft from the NP241 that came on the NV3500 to my NP246?

[@bman222112]

I believe they should interchange, yeah. There are two cuts of input for those tcase gears, but a '95 and 2000 should be the same. Gonna have to take both apart and compare them to be sure though.

[@rodriguezluisu87]

@@bman222112 thanks for getting back to me

[@dustins3185]

Hey I know this is long after you did this. I am doing the same thing to marry this up to my 700r4. Swapped the input shaft and have a very aggressive howling and grinding and I have no idea what it could be. I even replaced the planetary gear because the noise started after I replaced the input shaft so if figured the new part didn’t like the older worn part - still no luck. Any ideas?

[@bman222112]

Only thing that comes to mind is that the cut of the input/planetary gears changed slightly at one point and if you mix and match them you can have issues. Afraid I don't have much other advice.

[@ravenrivera1950]

Could be wrong bearing size! 93 and down t case has a different bearing from 94 n up look on off-road design they have some info that would help you

[@martinaleman7982]

Can you give me the brand and part number for the snap ring pliers. I saw you struggle a bit, so would you still recommend them or have found a better option?

[@SlowSTEN]

They're snaprings...Either struggle or break them. not many other options

[@SlowSTEN]

And their craftsmen...

[@etfarifax680]

What did you use to seal the case?

[@bman222112]

Just some normal RTV. The seal between the case and the transmission adapter didn't manage to take very well and it has been leaking quite a bit, but the case itself has not leaked at all. Pretty sure the one between the trans and tcase was my fault for not tightening it down enough before driving it.