need a little help with dana 60s

[gregamorton]

Guys I finally got my front drive shaft built and installed in my 71. My question is how much play is ok on the front end of my dana 60 high pinion. It looks like maybe a 1/8 of turn or so then a clunk. Does this mean it needs all new build or pinion depth reset? I am also wanting to know yalls opinion on the factory lockers that came in some trucks. I found one on ebay with a starting bid for around $125 shipped. It shows to be 30 spline is this correct for the 1979 dana 60 rear? Are the rebuilds reasonable for these? Thanks ahead of time.

[guhfluh]

Greg, research the difference between a Trac-Loc and a Power-Loc before buying a limited slip diff. There's a bunch of different spellings of the two, so try Em all. But, the bottom line is, you should get a Power-Loc and not a Trac-Loc. They are the best and most robust design of the factory Dana "lockers". The Power-Loc carrier has a V shaped ramp that the spider cross shift rides up when under load and produces mor force and friction on the clutches. One carrier is squared off like a top hat and the other is smooth transition and cone shaped. You should have the later, post-73 spline count, but I'd have to research to find specifics. You can upgrade axles to match the diff if you want as well.

[gregamorton]

can you tell me if this is the good one in this auction? http://www.ebay.com/itm/181465083395?ss ... 1423.l2649

[guhfluh]

No, it'll work in mild conditions, but a Powr-loc looks like this:
http://images.marketplaceadvisor.channe ... 78/dpl.jpg

[gregamorton]

ok sir what is a good price on one of those style units? Rebuilds reasonable?

[gregamorton]

well been reading up and there showing that in 1979 the f350 4x4 had a dana 61 or dana 70 rearend. How can you tell the difference between the 60 and 61? Also curious if any body knows if there is 3.31 gears that fit my truck if it has 60s or 61s. trying to get it ready for the cummins conversion. I do think that with 3.54s it would be fine when I do go to 35" tires. I drive most of time 55-60 so 1900-2200 rpm is fine to cruise at.

[guhfluh]

Are we talking front or rear? The Dana 61 should be cast with a 61 on a rib. The Dana"71" is a rear normally used for the F350 with a 61 front and both used for the 3.07 gears. That's all I know without researching more.

[gregamorton]

I got on randys ring and pinion and it stated dana 60 front and dana 61 or 70 rear. My truck was originally a factory 79 single wheel one ton. Maybe the factory duallys had 70s in them. I will investigate more in the next few days.

[guhfluh]

I believe what everyone calls the Dana "71" is actually a Dana 70-U, but if your truck has 3.55's, I'm pretty sure it isn't a 61 or 71, as they were used for the lower ratios and 3.55's are a normal 60's and 70's ratio.

Are you planning on trying to use the C6 with the Cummins? I have 3.55's in my 96 Ram 2500 2wd ExtraCab Long bed Cummins 47RE(4spd overdrive auto)with 34" tires, and it has no problem turning them over or lugging along at 50-85+mph in overdrive. I did build the trans, add intake, exhaust and turn up the pump, but otherwise stock.

[gregamorton]

yes add cummins in front of the c6. The transmission was rebuilt and has very few miles on it. I plan on adding a shift kit and larger cooler but thats about it. The 460 in front of it now is rather healthy. I just cant deal with the mileage much any more. My best tank so far is 7.8mpg. My old dodge I had with no OD with 3.54s got 14-15mpg at 55mph with a dripping injection pump.

[guhfluh]

How hard do you plan on being on the diff? If you don't plan on rock crawling, mud bogging or high speed one wheel peels, then a Trac-Loc holds up fine. It can be set up aggressive or soft and works fine before the clutches wear out. It'll keep both spinning in your basic wet grass, wet concrete, towing, etc. Just like all the newer factory Dana limited slips do, it is just an inferior design, isn't as strong for extreme use and wears out faster in my opinion, but it isn't "bad" to have.

I'd do some research on modifying the C6 for low rpm diesel use, but it should hold up fine. You'll probably want a lower stall in the converter and higher line pressure at lower rpm *might* be needed, but that's about all I can think of. The shift points will of course have to come down, and will probably require some spring changes in the VB.

Anyway, first thing is to verify for certain the axles and splines you have.

[gregamorton]

I want them for trails in the woods if I go camping. Mud, slick stuff not romping deep stuff or boulders or any thing really serious! Would the track loc work good on front and the power loc on rear? I try to keep mud off this truck and it has no grime on frame or anything. I wash the truck once a week including the underside. I do plan on adding some 9.00-16s one day and they are 35-36" tall. They sling mess every where even now with the 31"s.

Here is what I came up with on the diffs

front 620098r 023 3.54 d8ta ze 610023-1 4 20 9 48 100291 The front I could not find where it said 60 on it but number come up 60 every where on the internet.

rear 60 c-30255 3.54 d8ta tb 603901-1 I could not read the numbers on the tube on rear dana 60

[guhfluh]

The front comes up as having non-free running hubs, is it? If so, the driving characteristics of any limited slip or locker probably isn't going to be too fun and may be dangerous. An air locker would be much better in that scenario, but mucho denero... I'm not experienced with running one without free wheeling hubs or an pass axle disconnect at least, so I can't really be certain though.

The Trac-locs would survive what you want I'm sure, and if set up aggressive should work well, just go in knowing they'll eventually wear out and don't grip nearly as well as a power-loc.

[guhfluh]

Also, it seems as if the front axle os the sought after "Snowfighter" and has 35 spline inner shafts and diff. The rear is showing a standard 30 spline, but still better than my 67's 18 spline:)

[gregamorton]

Yea it was factory 400 4 speed and 203 with all time 4x4. Now its 460 c6 205 with locking hubs and mid 90s dually hubs. I won the track loc tonight and he says he has another he will check out to see the shape of. Won for $120 shipped to house. If he sales me the other for same and I put kits in that would be under $500 for both. Maybe a good way for me to go im not 100%.