This is a Dana 70 out of a 92 or 93 ctd cab and chassis. I was planning to use it in my Crew. Today, I finally got around to pulling the cover. The first thing I noticed is the magnet. Please see the pic below. Is this from normal wear and tear on the limited slip, or am I looking at more serious problems? I have never opened up a limited slip before.

The next thing I noticed is the rust on the ring gear. I have had this sitting around for a couple of years, and who knows how long it sat before I got it. Am I looking for a new ring and pinion, or can I clean this up and run with it?

Moreover, with what you see here, what would you recommend? I have another d70, but it is open and I want the limited slip. Thanks for anybody's 2 cents. Eric

 

If I were in your situation, I would remove the caps, remove the ring gear from the diff case, disassemble the diff, see what it needs, and have the ring gear bead blasted. A good visual inspection after cleaning will tell you what you need to do. Don't condemn it yet!

 

that sucks, try cleaning it with steel wool or scotch brite, see if the area is pitted to the touch, where you can feel it, the hardned surface is thin, a couple thousanths, looks like it had a sweat of moisture for a period, the other teeth look good, if it comes out decent, run it, and check it periodically, the magnet will have some metal, debris from the power lok will contaminate the gear oil, it should be changed around 25-30k, also a friction modifier should be add with posi type gl5

 

Thanks guys,

Sooty you said "power lok", is this a stock limited slip or is this aftermarket?

 

Power lok is a limited slip unit

"Power-Lok provides approximately 75% more traction than a standard conventional "Open" differential. Its two piece case construction with four pinion mate spider gears provides for more than double the strength of standard open differentials. Durable all steel clutch plates combined with unique torque applying cross shafts provides for long life and positive action."

 

its a dana option, military tested, very durable giving the cummins powertrain, not much fun to handle when out, the side spider gears spread under load, locking both side clutch packs, additional lock can be had when applying more brake pressure, at ratings of 98% lock, i love them, some pullers on this site have had some more negative demise with abuse, all the older motorhomes ran the dana 70, hauling tons of weight, to me its one of the best diffs ever offered to light duty.

 

Well the condition of the gears is now a moot point. It ends up they are 4:10s. I have been thinking for two years now that they were 3:54s. Since I am building my daily driver and will be running 305 by 16 tires I am pretty sure I want the 3:54s (unless somebody want me to put a ten-year endurance test on their Gear Vender's overdrive ).

Thank God for spare parts. I guess I will have M&H set up the unit in my other axle with the preferred gear set. Since I will need to go through the set-up process now anyway, I will go ahead and use my stock width housing and I won't have that 4 in. hub sticking out of the center of the wheel.

 

some complian about the 4500 gear spread, the 4:10 works for me towing, the gearvendor gives ms the same final ratio as a 3:54 truck, only i get 7 forward gears, awsome tow rig, i liked it so much, i put one on my jeep pickup, ive got 150k on the dodge one i bought new, i found the one for the jeep for 800. both n the 205 t-case, i change the oil 20k religiously, because the clutch pack does discharge metal, i think their good for the long haul with proper maintenance, they rate them for boat loads of torque.