Howdy, I just asked this in the 87-96 forum before I realized this really belongs here, so my apologies for crossposting. It's not something I normally do.

For my twin-turbo crewcab project, I've been working out the concept of an additional overdrive... mostly because the engine is based on a 460, thus forcing me to a ZF manual transmission. Because the engine is being configured to produce lots of boost down low, much like a diesel, I'd want to compensate for this with gearing in the axle. I could just replace the ring/pinion gears and call it a day in the existing sterling, but I've run across an opportunity to purchase fairly inexpensively, a 1-ton, two speed dually rear.

I've done some googling, but haven't been successful in finding enough information to determine if this is a good choice. I imagine it will slide right under, but one never really knows

Might anyone know if it would fit? Maybe dimensions between the insides of the wheels? Gearing? Can it be shifted "on the fly" at speed?

If I do go this route, I'd have to find dually-compatible SRW wheels, as I'm not going to be running the truck as a dually. Wider tires will be necessary anyway, but I'm not going not going to be adding the dually fenders to the rear however.

What do you guys think?

Unfortunately, all I know is that its a 1-ton 2-sp ford rear, the person who has it acquired it on a pallet, and wasn't able to determine exactly what it came from, though I'd wage 1-ton means F450. Are there any websites that provide info regarding this axle? Happy to do my own research, just haven't found anything useful so far...

 

I've never heard of Ford offering a two speed axle on anything smaller than an F650. I do know that the F450 has never had one, and I don't think the F550 did, either.

 

We had 2 speeds in our farm trucks, A '48 F-6 and a '58 F-600, and a 2 ton '51 IH. These were huge axles and would not work under a 1 ton.

I'd look at this axle, check the part numbers and manufacturer before I bought it.

While your engine may make most of it's power down low, it will still spin to 5000 rpm. The ratio spread in a ZF should hold you.

 

Supposively its a one-ton axle out of an E-something box van. Hmmm.

Like you guys, I thought two-speed rears were in the bigger trucks (F500+) but I'll be looking at it next monday so I'll have my F350 with me to haul it back (if I'm taking it) so I'll see what it actually is. It does have eight lugs like my F350, but that doesn't mean it will fit. Just looks "similar" in the very dark photo's.

I'll keep you'all posted.

85E150Six - Yes, in theory the motor could be revved to 5Krpm, however the way I'm building all this up is not to ever hit that. The "virtual" redline is going to be 3.5K, much like a diesel, which is why I was thinking a two-speed rear (or a ZF mounted OD unit, like in motor homes) would be a good option to compensate for the really low RPM range. OD units are in the $2K+ range, whereas this axle hub to hub is $50. Now you can see why I was attracted to it and curious

 

My dads got a scrap 91 L8000 Dump Truck with a 2-speed rear end. From what i remember the pumpkin is about 30". Its just way to big for a 1ton unless youve got a lift on it....a big one.

 

Yep, that is by far too big.

I saw this on e-bay, even though the auction closed and the guy didn't reply to any of my emails (like, what is this from, etc!), this looks about the right size... its certainly not a "big truck" part...

2-speed 1 ton ford rear If the link doesn't work its ebay item #4531638416

So based on seeing that auction, I've concluded that smaller 2-speed rears do exist... hopefully when I take a ride over to where the rear I'm actually considering is, it will be similar in size more or less.

 

Like every one else he smallest truck i have ever seen one in is a F-600. too bad that don't make them in a smaller size

 

2 speed rear axles are more unsprung weight anyway, something you do not need. You'd be better off with the Gear Vendor unit.

 

I wonder why the seller thinks it is a 2 speed. From the photo it sure doesn't look like anything but a standard one speed axle.

 

There hasn't been a small 2spd rear since the old Columbia rear end which was basicly an O-drive unit on the diff. I havn't seen one them in forever. I think they came out in the late 40s on what I can't remember off hand.

Pat

 

Normally a 2-speed rear axle has an electric motor mounted on the axle housing. That is how our two 3 tons are.

 

Well, I drove out to look at the rear this morning, and it is a 2-speed rear. There is a lever on the top of the diff (or the bottom?), and after shifting it back and forth there is an obvious change in gear ratio. It wasn't too massive, though by far larger than the Sterling that's under my F350 now. While in good condition, it's definately not going to fit. It is a very narrow rear though the wheels do bolt onto the hubs with 10 lugnuts. No markings of any kind, no tags, no depressions, no stampings. But it would never fit around my F350's frame rails so I left it behind.

still not sure what it is... but it's much larger than what I have, but certainly much smaller than a 2.5 ton rockwell, which I've also seen "live" in the last year or so.

Looks like I'll have to bite the bullet and do the overdrive thing as "plan C" if "plan B" doesn't work out.

Thanks for all the comments and help guys, very much appeciated!

 

time for plan D! wait, wtf is plan D?! hehe jk

What is the length of that 2 speed axle, do you remember?

 

Since it has just a lever it makes me wonder if it's older. I've seen a '46 Ford 2 ton with a 2 speed rear axle. It wasn't overly large, had 5 bolt wheels. To shift it there was a lever like the emergency brake on older 4spds but was on the right of the driver. You'd pull the lever and would pull a cable that ran to the differential and it would move the arm on the differential.

 

The length outside wheel to outside wheel matches my SRW sterling, outside wheel to outside wheel. The inside dimension with the duallys wouldn't fit.

I have the measurements in the truck, when I go out for coffee tomorrow I'll post it.