The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - questions about my 68 k-20 and lifting it

**Yukon Jack** · 11-18-2008, 04:27 PM

Looks like you're are getting some good info. I will commented that if your transfer case is original it should be a Rockwell T-221 which is a gear driven case. What is your transmission shift pattern - that will confirm whether you have an SM420 or SM465.

When I did my original 4" lift and later 6-7" lift, I did not have to modify my rear driveshaft or drop the carrier bearing. I do have the Rockwell transfer case and I had to add a double cardon joint to the front driveshaft and modify it's length, even with just the 4" lift.

11-18-2008, 04:27 PM	#7
Yukon Jack Post Whore Join Date: Feb 2000 Location: Rose Hill, KS, USA Posts: 12,689	Re: questions about my 68 k-20 and lifting it Looks like you're are getting some good info. I will commented that if your transfer case is original it should be a Rockwell T-221 which is a gear driven case. What is your transmission shift pattern - that will confirm whether you have an SM420 or SM465. When I did my original 4" lift and later 6-7" lift, I did not have to modify my rear driveshaft or drop the carrier bearing. I do have the Rockwell transfer case and I had to add a double cardon joint to the front driveshaft and modify it's length, even with just the 4" lift. __________________ 1970 Blazer with a 400 sbc and 4" lift 1980 Pontiac Trans Am, 455 Oldsmobile 2012 Kawasaki Concours 14