Detroit locker makes one... Part number 225S-58B

Alos check to make sure you dont have one. Alot of the trucks came with posi's and tehy just wear out over time. Might just need a rebuild.

 

Beware of buying one without checking your axle spline count.

 

The Dana 71 has squat for aftermarket support and unless something's changed, 3.07 is the ONLY gear ratio available for them. If you can't find parts for the 71, swap it for a Dana 70. If you don't want to pay the $$$ for the Dana 70, 14-bolt GM Corporate rear-ends can be found for a couple hundred bucks just about anywhere and they are the cheapest to buy lockers for. I wouldn't put a Ford 9-inch under a heavy-duty truck. They can't carry the weight. That's why Ford didn't use them in anything heavier than a 1/2 ton.

 

They would have to swap it for another Dana 71 if they kept their automatic. With the 3spd. auto, you have to have 3.07's to go highway speeds.

If they swapped for a 518 though, then there would be more options for them.

 

Randy's sells 4.10 and 4.56 gears for the 3.07 axles.....

 

Thats because there is no such thing as a Dana 71 thats why you are having problems fining aftermarket stuff . Try looking for a locker for a dana 70U.

D70 standard - same size carrier and pinion bearings as a D60 along with the same size pinion....bigger carrier and ring gear.

D70U - the same size bearings, gears and carrier as a standard D70 but the housing has an offset pinion bore to allow for a pinion gear with a higher tooth count to allow ratios less than 3.54. Gearsets with a bigger ratio can be installed but they use an extra thick ring gear. Carriers and gearsets aren't regarded as interchangeable in parts listings.

D70HD (sometimes referred to as the hybrid 70/80) - Uses the same pinion and pinion bearings as the others but uses a D80 carrier and bearings. Carriers definitely don't interchange with other D70's and the gearsets aren't listed as interchanging in parts listings. Carriers can interchange with a D80 but slotting of the ring gear bolt holes is required in the carrier.

All 3 housings vary from each other to allow for their different combinations of internals.

I don't have any first hand info that would lead me to believe that the carriers will interchange between a D70 and a D70U. I would think they would be identical other than the raceway diameter for locating the ring gear on the carrier might be a slightly smaller diameter on the D70U, though, I can't confirm it. I haven't dealt with very many D70U's.

And as logan said Randy's ring and pinion has your hook up.

 

Right here is a bearing kit for a Dana 70U / Dana 71, so aparently 71's do, in fact, exist.

Master Overhaul Kit Dana 70U & 71 Master Bearing Kit :: Dana :: Diff Install Kit :: Power Train Truck & Auto Parts, Inc.

 

What ever man, Not a big deal but if you want parts for your rear in a 3.07 geared 727 dodge 250, you need to look for a 70u

 

yes they do exist
what hes ^^^ telling you is you cant find parts for them so UPGRADE to the 70u I got a 70 HD i will sell ya 3.55 gears 35 spline axles $150 plus shipping free delivery up to 50 miles

 

Sorry RSWORDS. I wasn't trying to come off sounding like a dick. The original poster was just looking for info for the axle in his truck, but was being told the axle didn't exist when he was sitting there looking right at it. Didn't want him to think he was going crazy.