The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Gear vendor's with 3:54 rear gears and th400?

**chewychevy67** · 03-03-2018, 12:22 AM

I'm wondering if I could get them to program the computer to get the Overdrive to shift in at 52-55 mph instead of 47 mph. Would that help this setup? It would keep the rpms higher into the shift. I could easily change the rear to 3.73 but my diff has new gears in it now and it's nice and clean. If I'm changing Maby 4.10 gears could be a possability if they will fit in the same case but that I'm not sure of.

03-03-2018, 12:22 AM	#25
chewychevy67 Senior Member Join Date: Jan 2010 Location: Here Posts: 5,592	Re: Gear vendor's with 3:54 rear gears and th400? I'm wondering if I could get them to program the computer to get the Overdrive to shift in at 52-55 mph instead of 47 mph. Would that help this setup? It would keep the rpms higher into the shift. I could easily change the rear to 3.73 but my diff has new gears in it now and it's nice and clean. If I'm changing Maby 4.10 gears could be a possability if they will fit in the same case but that I'm not sure of. Last edited by chewychevy67; 03-03-2018 at 12:55 AM.