We have a 1965 Chevy C-60 truck that my partner made a ramp truck to haul our rail dragster on. I built a stout 383 smallblock to pull the beast, with a 4spd manual and a 2-speed Eaton C15 rear. The gears are like 6.40 high and 8.72, so even with the tall tires we are cruising 60mph at 3100rpm. To take the rail to races far off, via interstate, I would like to get the revs down to the mid 2000s, say 2500-2600rpm. Who is the go-to guy for Eaton 2spd. ring and pinions, or is there a source for a bolt-in 5-speed O/D trans to get these revolutions down? Thanks in advance!! RB
You probably need to go more late model dually rear end with higher gears, and ditch the two speed rear for starters. Then a late model overdrive automatic, or one with a Gear Vendors attached. But, it's not going to be cheap no matter what you do. An inline Hone overdrive would work with what you currently have, but those are really expensive. Your partner welding without a mask/shield/goggles? I am Butch/56sedandelivery.
I'd have to ask him what it is called but my buddy runs a 2 speed overdrive box that actually sits in front of his 4 speed in his mid 70's 1 ton. He picked up several mpg while hauling a camper with it with that setup.
google Brownie box a divorced overdrive if that rear axle is a Rockwell, gears up to 5.29 are avalible
I am using one in my bus (f600) going to purchase an advanced adaptor bell kit to get rid of the hydraulic throw out bearing
A complete rear end out of a later model medium duty truck that came with a diesel and hydraulic brakes would likely be your cheapest and easiest solution. Because diesels have a lower governed rpm, trucks with diesels have numerically lower axle ratios than gas burners. The frame width on medium and heavy trucks is usually a standard width across all manufacturers, either 34 or 34 1/2 inches, as that makes it much easier to mount bodies, etc. It also makes axle changeouts easier and you have a choice of axles that isn't just limited to trucks of the same brand. You wouldn't even want to hear the price for a ring and pinion for the truck you have. Based on my experience in buying a lot of parts for various medium and heavy trucks in my dad's business over the years, the parts to change the ratio on that axle would likely cost twice as much as you paid for the truck.
https://www.proformancepros.com/cgi-bin/commerce.cgi?preadd=action&key=ZBG-F106 Rockwell f106 5.29 gears $400
That's a good point. Ford used the 5.9 Cummins in some medium duty trucks and school buses on the late 90s. Those things are set up to top out around 2600-2800 rpm.
what type of rims bud or clincher? Im not very far from you and I have an F450 Dana 80 with disc brakes 463 gears these are rated at 11k pounds it has the 10 bolt pattern that is similar to GMs 10 bolt just has larger studs and the center opening needs relieved to use gm wheels on it
i have a brownie box,a 3 speed,one gear underdrive,then direct,then one gear overdrive. Rebuilt about 10,000 miles ago,i have driveshaft yokes and everything you need. Hell,ihave 2 of them,$750 for both of them.. Located in SW Ga.
Called my partner this morning and we are definitely considering this route! I will let you know ASAP! Thanks!
The brown lipe box or a 5speed is the way to go. I went from 8.25 tires to 10.00 and gained a taller gear on a ford f600.
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