Posted by CGarbee on Saturday, August 12, 2006 at 11:41PM :
In Reply to: Duane...................Picture posted by Paul (in NY) on Friday, August 11, 2006 at 7:40PM :
The URL for the Yahoo Cummins 4BT group is:
http://autos.groups.yahoo.com/group/cummins4BT/
The GM flywheel, clutch, and manual transmission setup is the rarer of the GM transmission setups to be found these days... Conversations that I have had with fleet managers who have maintained route vans with the Cummins 4BT in them is that the driver's had such a tendency to ride the clutch that most of the companies decided to go switch the tucks to automatics... The TH400 is a very common transmission in the GM chassis breadvans, the version by Freightliner (they purchased the GM Custom Chasis plant) has a ISB3.9 Cummins backed by an Allison automatic (actually, the current version has the Cummins as the alternate engine with a MB engine as the "standard" powerplant).
I think that a beter transmission option is (in no particular order, depends a lot on your plans and ability to source and fabricate): ZF five speed from a Ford F250/350 HD, NV4500 from a Dodge, Spicer 3053A from a military M35A2 or M35A2C 2.5 ton truck...
Enjoy.