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Russell · 12-11-2005, 04:13 PM

Jim, what you need is a transmission crossmember from an early SM465 truck (like 73-78 or so). They have two large humps in them to allow for dual exhaust to travel underneith them on either side of the transmission. Your 83 will have a crossmember that probally has a single downwards dip in it for the factory single exhaust to go overtop of it. Depending on which transmission you are running, you'll likely need to drill a new hole in the crossmember (most of the SM465s I've seen of that era have two bolts holding the tranny down at the back, while many of the newer transmissions only have one in the center, and you'll definitely need to drill new holes in at least the lower plate of the frame.

The crossmember is a 3 peice unit, the big member that goes all the way across, and sits on top of the bottom plate of the frame, with two little supports that go to the top of the frame. Those upper plates are not essential to the strength of anything, so you can choose to omit them if you wish.

BTW -- You have a PM

12-11-2005, 04:13 PM	#2
Russell Professional Grade Join Date: May 2003 Location: Fort McMurray, Alberta Posts: 7,915	Re: need exhaust help with engine swap Jim, what you need is a transmission crossmember from an early SM465 truck (like 73-78 or so). They have two large humps in them to allow for dual exhaust to travel underneith them on either side of the transmission. Your 83 will have a crossmember that probally has a single downwards dip in it for the factory single exhaust to go overtop of it. Depending on which transmission you are running, you'll likely need to drill a new hole in the crossmember (most of the SM465s I've seen of that era have two bolts holding the tranny down at the back, while many of the newer transmissions only have one in the center, and you'll definitely need to drill new holes in at least the lower plate of the frame. The crossmember is a 3 peice unit, the big member that goes all the way across, and sits on top of the bottom plate of the frame, with two little supports that go to the top of the frame. Those upper plates are not essential to the strength of anything, so you can choose to omit them if you wish. BTW -- You have a PM __________________ 1995 Chevrolet 2 Door Tahoe (6.6L LBZ Duramax / ZF6 / NP241 with 1 ton solid axle swap) Last edited by Russell; 12-11-2005 at 04:13 PM.