2-speed rear end - questions

[hofilbert]

I am looking at another '70 barracuda and this car has been upgraded from a 318 to a 426 w/727 and the seller said it has a 2-speed rear end. He has a switch by his seat he reaches down and changes performance level. Now, I understand the high/low for performance and hwy, but what is it? Factory? aftermarket? who made them? Worth $?
I've never heard about them on a cuda and don't know much about them. Are they rare? or good to have? or not?
Thanks for your time.

 

[AUSTA]

Could be gear vendors over drive it works on a switch i have one on my TA with a 3.9 diff
can be switched manually or by automatic speed activation

 

[rklein71]

Trucks sometimes have two speed diffs, Eaton makes one. They are huge.....

 

[Canuck74]

I've only ever heard of and seen them on Big 1.5 ton+ trucks. It does sound like an overdrive unit behind the transmission to me.

 

[autoxcuda]

Hone-O-Drive was the 2 speed aftermarket rear offered in the mid to late 60's.

I've heard of Shelby's with ?dealer? Installed with 9" rears.

Never heard of a 8 3/4 rear version. But I don't study them. An not much info on them.

In an old Hot Rod or something magazine of mine there's and product announcement of the Hone-O-Drive. And aluminum unit with a lever on the side of it. Would have to have the driveshaft shortened.

 

[autoxcuda]

Ok google search brought back some hits:

Hone Manufacturing Co.

Please School Me On Hone-0-Drive Overdrives

 

[IRON MAN]

There is the possibility the two-speed rear is one that Dana Corp offered back in the late 60's designed specifically for the Mercury Cougar. It was basically a redesign of their truck 2-speed unit. It works like an overdrive. I have looked for decades to find this extremely rare rear end. There is a picture of it in Petersen's 3rd Edition BASIC CHASSIS, SUSPENSION & BRAKES.