Re: Olds Drivetrain
There are 2 different tcases used in the Bravada
The BW4472 was used up until '97 or so. Same case as the Sy's and Ty's run. Its a pretty well built piece of hardware. Capable of 9 second passes, if you've got the power (Robert in Sweden runs one in his street driven 9sec Sy, for example). Would probably be a good idea to check the chain, it tends to stretch and then jump teeth on the sprockets.
The NV136 was used from '98 and up (or was it '97 and up, I never remember). This is an active on demand tcase (basically a normal 4wd box with a big clutch to kick the front end on and off). In order to use it as an AWD box, you've got to have something (like a computer) to activate the clutch when needed, otherwise its a 2wd tcase. The NV136 is pretty durable, and there is a step above it, the NV246, which is a Heavy Duty 2speed version of the same transfer case (there's also the NV236 which is a 2speed version of the NV136). For my application ('99 Bravada with a 6.0L and 80E) the easiest solution to how to mate the tcase up to the 80e was to go from a NV136 to a custom built NV146 (New Venture doesn't build one, so I had my tcase builder build a NV246 and leave out the low range parts (for reduced rotating weight since it's NEVER going off road)).
'JustDreamin'
