Early Ford Overdrive options?

[umr_engnr]

The problem with the gear vendors in 4x4 is not just that it is placed after the t-case. While going in the forward direction there is a directional sprag that holds everything together. However, when going in reverse the only thing holding everything together is the conical clutch. If you get in a bind off road and have to reverse, you risk burning up the clutch, which could disable the device. This is the same reason gear vendors advises against reversing while attached to a load. This does not seem like a reliable solution for 4x4 vehicles.

I am in the same boat as you with my c6, 4.10 gears, and low RPM diesel. Getting over 60 really makes the engine scream. I have been searching for a tough and reliable overdrive solution, but so far haven't found anything that fits the bill. I have a design for a mechanically shifted overdrive that I am hoping to get machined up. Goal is to work behind an automatic, but have a strong direct drive, and no clutches to burn up. It would be placed before the tcase and simulate a factory overdrive. If there is interest from other people here, let me know, so that I am not wasting my time and there will be a market for this thing. Thanks.

 

[ExpoMike]

Actually I talked to GV about this reverse issue and their answer was, if you are backing up a steep grade or with a heavy load, put it into 4WD which will take some of the load off the internal clutch system in the GV unit. Not a perfect solution but given the available options, one that could work okay.

 

[umr_engnr]

That's fine as long as you aren't off-roading and your front axle doesn't have traction. I'm not saying their unit is bad (although it is quite pricey for a design that hasn't changed in almost 50 years). However, in a world of non ideal solutions maybe it is acceptable.

 

[Wood Kutter]

Why don't you just try an AOD-EW/4R70W non-electronic 4 speed ? I put one in a custom 1974 Econoline I did years ago.

 

[Wood Kutter]

http://www.transmissionadapters.com/Ford 429-460.htm
http://www.429-460.com/t526-aod-behind-a-bbf

 

[fishtheduece]

The problem with the gear vendors in 4x4 is not just that it is placed after the t-case. While going in the forward direction there is a directional sprag that holds everything together. However, when going in reverse the only thing holding everything together is the conical clutch. If you get in a bind off road and have to reverse, you risk burning up the clutch, which could disable the device. This is the same reason gear vendors advises against reversing while attached to a load. This does not seem like a reliable solution for 4x4 vehicles.

I am in the same boat as you with my c6, 4.10 gears, and low RPM diesel. Getting over 60 really makes the engine scream. I have been searching for a tough and reliable overdrive solution, but so far haven't found anything that fits the bill. I have a design for a mechanically shifted overdrive that I am hoping to get machined up. Goal is to work behind an automatic, but have a strong direct drive, and no clutches to burn up. It would be placed before the tcase and simulate a factory overdrive. If there is interest from other people here, let me know, so that I am not wasting my time and there will be a market for this thing. Thanks.

I am looking for the exact same thing for my RV with a 4.10. Looking at the GV option but a little much, almost as much as the RV was. Let me know what you come up with.

 

[Heading Out]

What about one of the old Brownie box transmissions? It has an under, over and direct gear. not the most modern, but it gives you more choices.

an underdrive to lower gear ratios for the trail, direct, and overdrive for the hwy.

it could be set up behind the transfer case to only work in 2WD, but, with a divorced transfer case, the Brownie would work in 4WD as well.

The drawback to this set up would be the number of U-Joints in the power train. but there should be plenty of room under you big 'ol vans.

 

[r_w]

PLENTY of room....

If you don't need a fuel tank.