2ktransam

iTrader: (12)

Hey guys. I'm trying to finish up my engine swap and 80e swap in my 1500 silverado. I got the input shaft for the transfer case from a member on here that had it in a np246 autotrack transfer case. When we took my np261 apart (manual shift transfer case) we noticed that the pilot bearing woudn't fit the new input shaft. Is there a different input shaft that I need for the transfer case I have to work with the 80e?

We are debating just milling out the input shaft I have to except the bigger pilot bearing. Would that work?

Please help. Thanks

2ktransam

iTrader: (12)

One thing I just thought of. Does the 80e input shaft get a roller pilot bearing like the 60e shaft had or does it just use a bushing?

bohr898

iTrader: (6)

i have an np 246 t-case(autotrac) and when i ordered my input shaft from gm i got an input shaft that had too big of a roller bearing on the back side and wouldnt fit my t case it had soo much slop... prob about 1/2 inch too much clearance... i returned it for the correct one,,,,,,same price



bottom line... yes they are different... the autotrack input shaft has a smaller pilot bearing than the manual t case from a 2500..... im pretty sure the manual t case can hold gobs more torque than the autotrac too

bohr898

iTrader: (6)

milling it out would probabily work... but then you would have to buy another im sure is expensive bearing.... i just buy the right one and then return ur old one claiming it isnt the right one and say u got the correct one offline

warsteiner

Did you ever get this figured out? I'm fighting the same thing now on my NP261 in my 2005 silverado. Swapped to a 4L80E and purchased the 32 spline input. The Bearing that this shaft takes is smaller and will not fit the transfer case main shaft on the pilot. I have tried many machine shops and they cannot mill out the input OR turn down the pilot. Both the input AND the main shaft are hardened and the cutting tools wouldn't scratch either of them. I'm very aggravated with this and have no idea what to do. The 27 spline input takes the large bearing and the 32 spline takes the small bearing. But according to GM and new venture there is only ONE mainshaft for the np261 and the np263. The NP246 lists a .630 wide bearing and a .940 wide bearing. Where is this measurement coming from? Also my NP261 has a 3 pinion planetary where the parts diagrams only list a 4 pinion and a 6 pinion available...

2ktransam

iTrader: (12)

I did get mine figured out. I had to order a new input shaft from GM to get it to work. I will pm you my number so we can discuss it.

warsteiner

OK i got this taken care of this weekend. The input shaft i recieved first was incorrectly packaged. The NP261 and NP263 only have one choice of pilot bearing. The input gear i had first was actually an NP246,243,241 specific piece. I now have the CORRECT part sent from TBTrans in washington. And the price was wayyyyyyy better than actual GM cost on it. Part number 42740 (NP261/263 input 32 spline large bearing) from T&B Trans and gear in Deer Park, WA. Terry is extremely knowledgeble and VERY helpful. He didn't wanna know what i needed... he wanted to know what i had and what i was trying to do, and he said no problem....

2ktransam

iTrader: (12)

Glad you got it figured out. I got the part number from GM but its $300 so you were better off.