Re: 6.0L swap w/4L80E - Transfer case??
Hey, this one is up my alley....
I've got a '99 Bravada with a 2004 6.0L LQ4, 4L80E, and a custom NV246 with no low range (effectively making a NV146, which New Venture doesn't offer). The N246 has the correct 32 spline input to mate with the 80E output without modification, so it just bolts up.
Here's the sticky wicket: The NV136 and NV246 are "active-on-demand" transfer cases. Which means they're not truely AWD torque splitting units. Basically, instead of having a viscous coupling arrangement, they've got an electronically actuated clutchpack that turns the front output shaft "ON" on demand. So, most of the time, you're cruising around in 2wd, and when the computer detects wheelspin (via wheelspeed sensors) it kicks on the clutch for the front shaft. It also kicks in the clutch automatically at speeds below 5mph (for when you leave from a stoplight, for example).
The controls is the big issue in doing the NV136 or NV246. In my case it was a non issue, because I already had the controls, since my truck came with a NV136 and the appropriate controls from the factory. Bravadas after '97 used this type of AWD system, and you could get it as an option on Blazers and Jimmys for the same model year range (although it seems few people chose that option). I expect you could figure out how to switch 4wd on and off (with a toggle switch or whatever) but you would loose AWD, since it would plow like a dumptruck with the front end engaged during some types of manuevers (and no viscous or differential device in the tcase).
With the BW4472 (the Ty / Sy tcase) the issue is strictly the mechancally adapting the splines / rear of the trans to the tcase.
As mentioned by George Blake, the LSx motor uses a slightly altered SBC pattern. There is an extra hole at the 12 o'clock position, and the hole at the 2 o'clock position (just below the pass side head) is not used (because on an LSx motor there is a water jacket there. Don't try to drill the extra bolt hole in the block).
I can tell you, the conversion is TIGHT! There isn't a whole abundance of excess room under the hood or under the truck. Some of the parts are available (mounts, oilpan should be out), but some of it is still left to your imagination (like exhaust manifolds / headers).
'JustDreamin'
