The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 454 Dually with 4.56 rear diff, what auto trans to use

Tom · 12-21-2021, 07:29 PM

Considering I've towed a square body with another square body using 3.08 rear gears with a vortec 350, I think you'll do just fine re-gearing. That being said, I'd re-gear [to 3.73 or so depending on wheel diameter] AND stick an overdrive in there. But 4L80 is the only automatic trans option in a 1 ton, and its expensive plus requires a stand alone computer controller that cost a metric crap ton more then it should.

12-21-2021, 07:29 PM	#7
Tom driving is in my blood Join Date: Dec 1999 Location: Mesa AZ Posts: 5,695	Re: 454 Dually with 4.56 rear diff, what auto trans to use Considering I've towed a square body with another square body using 3.08 rear gears with a vortec 350, I think you'll do just fine re-gearing. That being said, I'd re-gear [to 3.73 or so depending on wheel diameter] AND stick an overdrive in there. But 4L80 is the only automatic trans option in a 1 ton, and its expensive plus requires a stand alone computer controller that cost a metric crap ton more then it should. __________________ -78 c10 short/step: 388cid, M20, 5/5 drop, lots more. Playtoy and first vehicle. -98 c1500 x-cab: 5.7L, 17" rims, 5/6 drop, flowmaster, helper bags,NBS rear disk brakes. -02 Suburban 4x4: leveled front -CBR600F4i, CBR600RR, CBR1000RR, and standup skis DISCLAIMER: I cant spell for the life of me.