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Discussion Starter #1
Picked up a 89 2500 ram 4x4 shell.
Has 3:07 axles d61 and 70(71?)...
The pinion yoke has about 3/4 inch or more of back and forth play (backlash?)...
At the minimum I would like to get seals, axle joints and kingpins in it.
If the play is excessive from wear or other form of cause can you just shim it to the tolerances that are acceptable?
I've had a 14 bolt with an inch of play in the yoke with no noise or problems in a DD for years. They are going in a 12v 1st gen and it'll be the last one I ever do so I'd like to get it setup once.
I have a bunch of 1st gen sheet metal and shell parts if anyone is interested...
Thnx in advanced..
 

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3toe, those 3.07 axles are kind of rare. Only came on trucks with the TF727. The front is a Dana 61. The rear is a Dana 70U2A. There is no Dana 71. A few years back you couldn't give those things away and now they draw a big premium on the market. The replacement ring and pinon for those aren't exactly common either.
 

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Discussion Starter #3
Yes unicorn hens teeth. Just want to know if I should try to get backlash out by shimming..
 

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A little play in the pinion doesn't necessarily mean that the gears need to be shimmed or reset. Pulling the inspection cover and checking the pattern on the ring gear teeth may help determine that. Or better yet, a gauge to measure backlash like in the pic below.
Also, unless the front wheels/tires are leaning, the kingpins are probably fine. Just get out the grease gun, pack them full of grease, and call it good. And, if you do have to replace the kingpins, do it when the front axle is bolted down to the truck. Getting them off a loose axle is a real pain. Don't ask why I know that.
 

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Discussion Starter #5
Its going to get a minimum of joints and seal probably king pins. Yes pins while in the truck are easier jt..I use a short 1x1/4 inch flat stock and weld it to the pin..whack it with a hammer and it isn't a fight. The heat from the weld helps and they come out super easy. Carrier is going to be out so I guess it will ultimately get setup. Yes if pattern is looking nice but has excessive play would it be ok to take out the lash? It would then deepen the pattern? It's been a while since I've done them. I suppose it's like riding a bike..
 

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As rare as those axles have become, probably would be worth the time to go completely through them. Get them in 1st class condition and if you didn't decide to use them they would be in prime condition to sell.
 

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As rare as those axles have become, probably would be worth the time to go completely through them. Get them in 1st class condition and if you didn't decide to use them they would be in prime condition to sell.
That's exactly what I did with my front D60 and rear HD60. Every bearing, seal, kingpin, axle u-joint, rotors, calipers, and pads. Rear Detroit Locker and front Detroit TrueTrak. And, rear disk brake conversion. Expensive endeavor. But, they are better than new.
 

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Well said J10Mike. Not sure there are even any lockers that fit those particular axles though. Don't know if Dodge offered one on that model. I also had thought a rear disc conversion would be nice. Might be able to just source parts of a regular Dana 70 to do that part.
 

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Well said J10Mike. Not sure there are even any lockers that fit those particular axles though. Don't know if Dodge offered one on that model. I also had thought a rear disc conversion would be nice. Might be able to just source parts of a regular Dana 70 to do that part.
Charles, Eaton now owns the Detroit Locker and Detroit Truetrak line of carriers and they still use the Detroit name. They are made for both the Dana 60 and Dana 70 axles.
 

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Mike the question would be did they ever make parts for these axles? The Dana 61 front axle is special and doesn't use the regular 60 parts. A locker for the 70U2A may or may not exist either. There again that is a special made unit. Seems there were only 2 gear sets ever on that one. 3.07 and I believe a 3.55. Wonder if Dodge offered any limited slip unit on those truck's rear end.
 

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Mike the question would be did they ever make parts for these axles? The Dana 61 front axle is special and doesn't use the regular 60 parts. A locker for the 70U2A may or may not exist either. There again that is a special made unit. Seems there were only 2 gear sets ever on that one. 3.07 and I believe a 3.55. Wonder if Dodge offered any limited slip unit on those truck's rear end.
Charles, I believe that Dodge offered and Dana used an optional Trac-Lok limited slip differential in those 89 thru 91 D70U2A axles. I've never heard of a LSD or locker made for the front D61. There may be. But, just never seen or heard of one.
 

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I suspect anything there would need to be custom fitted. If any serious off road work is planned, some type of locker is necessary. I only got stuck one time with open differentials and added a Lock Rite to my front end and never got stuck again. Have to be careful with dual lockers as they can put you into the ditch, especially on snow and ice.
 

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3.07 and 3.55 used the same carrier,basically a fast ratio limited slip will work.... only the housing and ring and pinion are unique. .... your's is probably the 35 spline which is different than the late 91+ which is 32 spline. You can tell the difference without pulling an axle on the rear by the axle end ... 35 spline have a tapered cone under a stud with a nut that requires a 5/8" or 11/16" wrench, 32spline have a flange bolt that requires a 9/16" socket or wrench . Early 60/61 used 8 9/16 wrench sized bolts ,whereas 32 spline front used Allen head socket screws.....
 

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Forgot to mention that any Cummins powerllok (limited slip) ,or Detroit locker will work with the 3.07 (8) as long as you have the correct splines as described above. .. on a 70 I believe that the split is 4.56/4.88 .... 60/61 split is 4.10/4.56.... dodge didn't put many Cummins trucks out with deeper than 4.10, airport tugs had 7.17 but are very rare. Even the 7.17 had a common carrier which would be the slow carrier. ..front powerllok would likely be a 35 spline 60 unit
 

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Also don't change the pinion shims on either axle, just shim the ring gear to the correct depth for oil clearance against the pinion , and side play....I usually set as close to the pinion as possible without any binding, testing a full circle of the ring gear.... usually there is a spot that is a little tight...... the existing play is most likely the spider gears,or the pin is loose in the carrier. ... if that pin falls out you have instant ****! !!!!!
 

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Discussion Starter #17
Good info hemi. The 61 feels pretty good on the pinion yoke the rear has about a 1/4 inch back and forth play on yoke..
 

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3toes, in post #17 backlash 1/4" but #1 you said 3/4" ! , so I thought I would post 3 pages (there are 12) from my Toyota Land Cruiser repair manual showing the crown (ring)& pinion mesh patterns. The dial indicator, crown runout not more than 0.004", backlash 0.006-0.008" . If crown or pinion need replacing do so as a set ! If anyone finds this helpfull or would like all 12 pages I will be glad to post or email . My email is ([email protected])

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View attachment 123427
 

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