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Hi guys,

Maybe someone has seen or done this before. I have a 98 Dodge 12 Valve. I found a donor to swap the frame over to 4x4. Typical Dana 70/60 combo is what I have. I really want to run 3.21 or 3.08 axles. I was thinking of getting a late model GM 14 bolt disc brakes and regearing to 3.21. I used to have a 1991 D250 with the Dana 71 3.08 gear set. I saved the ring and pinion from that axle, but the tubes and housing were toast.

I don't think there are any options for the front Dana 60 to get below (numerically) 3.54. I am trying to come up with a solution to get the front to match the rear and wonder if there are any magic rabbits hidden in hats out there.

I could match the ratios if it were a front Dana 44, but word out there is a 44 will get eaten up quickly by a 6bt's weight and torque. This is strictly a street rig, stock loving the highway and good mileage. 4x4 would only be used to keep from getting stuck on occasion. In my search I learned that the 14 bolts and also Ford Sterling axles were heavy duty and could be geared faster then 3.54 that is so common. Of course the rare Dana 61/71 combos pre-91 Dodge.(narrow track width and the front is opposite side drop of the current Dana 60) But can't find anything for the front. Maybe the really ambitious guys could put dana 60 tubes on a 44 center, albeit weaker in the gear set, the outer ball joints and such would be heavy duty?

I heard some place that people had flipped a rear axle over and put it in the front... Sounds nearly impossilbe, but...
Any ideas, or am I just out of luck. (Stuck with 2wd and preferred gearing, or 3.54 is as far as I can go)
Thanks in advance.
Greg
 

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Finding higher ratios can sometimes be a challenge. First off, there is no such thing as a Dana 71. That rear axle used in the early Dodges was a Dana 70U2A and had 3.07 gear ratio. It only came with the TF727 transmission. Those gears don't fit a standard Dana 70 because the axle housing are different than the one made for the 3.07's. The front axle on those trucks was a Dana 61 and it's gears don't swap into a Dana 60. If you front 60 is the high pinion model, 3.54 is probably your highest ratio. Those Dana 70 and 61 axles used be cheap as dirt but now they are like buying gold.
 

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Those Dana 70 and 61 axles used be cheap as dirt but now they are like buying gold.
Yep. And to think I couldn't give a pair (D61/D70U) away. Nobody wanted them. Ended up taking both axles to a recycler. Now, they are worth gold in just ten years time.
 

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Discussion Starter #4
Char1355 Thank you for the reply.
I am by no means arguing. You are right about the Dana 70 not being a Dana 71 it a catch name for the different offset Dana 70. You are also right that it the gear sets do not interchange.
However, this man on youtube was able to put an old set of 3.08 in a newer Dana 70 housing.
Title on YouTube: How to intstall Dana 70 3.07 gears into a standard or 70HD housing (or 3.21sx or 3.42s)
Not allowed to post link yet...
I am a machinist with a shop and can do the same to make my 3.08 fit in my newer (1998) Dana 70.
I am considering this. The other option is a readily fittable 3.21 in a GM corporate 14 bolt. No magic necessary. The real stumper is the front axle.

The Dana 61 with 3.08 was a pass drop axle like the Chevy. The 1998 Dodge Dana 60 is Driver's drop. Would a gear set that fit a driver drop also fit a passenger drop, or are they somehow meshed differently?
I wonder if I could find a set of 1990 Dana 61 3.08 gears and do all the same cutting the carrier, bearings etc and make them fit the Dana 60 then I would have a matched pair in original tubes.

I just thought that there might be something I am overlooking. Something that fringe gear heads know about for their specialized rock buggies. But those types are usually going deeper like 5.38 ratio and not the direcction I am going. Perhaps the the junky Dana 50 articulating axle that Ford used for a bit under their F250s or some other hidden gem like the 14 bolt or sterling axle. Maybe you can put bigger ball joints into a Dana 44 and convert it to Dana 60 sized ball joints.

Thanks again for the info.
Greg
 

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To my knowledge, the Dana 60 and 61 front gears don't swap, at least not without some serious work. However, see no reason you couldn't convert a passenger's drop to a driver's side. A matter of changing the axle tubes and axles. The pumpkin is the part that's different. The big challenge may be just finding one to use. During that fuel saving period, Ford also had a 10.25 axle with 3.08 gears. But, it was only available in 2wd. No matching front axle was ever offered. Ford Dana 50 axles don't have any high ratio gears either. In the earlier days the front and rear axles used the same gears so a low pinon front could be done. With the older stuff the pinion is running against the back side of the gear tooth. There were even Dana 70 front axles but they are quite rare. Might be easier and cheaper to add an auxiliary transmission with an OD gear. You probably aren't planning on cruising the interstate in 4x4 anyway. One of the brownie units would be one possibility. Although not cheap, the Gear Vendors units will hold up with a 6bt so long as you don't go nuts with the power.
 

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Discussion Starter #7
Well, it seems like the rare 1990 dodge 3.08 are the only options out there for a pair of fast gears. I appreciate all the help, and thoughts regarding tires gearvendors etc...

I found an extra Dana 70 on Facebook. I am going to pick it up and attempt to install my 3.08 set in it. It has been done and I am confident I can do it too. I think I will ebay a set of 3.08 ring and pinion front. And attempt the unprecedented install of 3.08 in the front at a later time. If the rear goes south I can simply swap back over to my original axle 3.54 and either live with it or look into my gearvendors options.

My buddy put a gear vendors in his 4.10 cummins based on my recommendation and he broke it backing up a cattle trailer. I know everything can be broken, but it is still highly disappointing and makes me rethink my love of the little overdrive. You do get gear splitting, but 3-4 or direct to overdrive is the real issue here and double over in a 3.54 is probably too steep. Furthermore, the overdrive ratios are probably too close to have a significant benefit (.69 and .75). Probably work well with 3.73 gears but doesn't fix the fact that both overdrive ratios are almost the same. Gear sets are available in that direction however. With 3.08 I think my stock-ish Dodge will pull better. I can run in direct with a trailer and go faster then 55mph. Use overdrive the rest of the time and she has plenty of grunt to get started. Especially with my low stall converter and my new HE351CW turbo.

Maybe there is flaws in my logic. Please feel free to correct or point. Thanks for the helpful info.
Greg
 

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The Gear Vendors units are not unbreakable. One issue that some don't adhere to is they cannot be engaged at low RPM. If you want something in the more mechanical range, look for something like a 5831B Spicer unit. However, it's factory torque rating is not all that high. It has a .85 OD gear which with your 3.54 would come out as 3.01. A stronger possible unit would be 7041. Those came behind diesels. That is a 4 speed unit with a .83 OD. That would give you a 2.94 final drive gear. The issue with the heavier units can be their physical size. A 7041 in over 2 feet long. We have members on the forum who run some of the Brownie units and they might give you some ideas. I always thought they were a good idea because if you needed to shift back to a lower gear for heavier work it was just a matter of changing gears.
 

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MMMM another post has disappeared on me.
Posted before, good luck finding 3.08 gears for a 10.25. They are up there with Unicorn droppings.
Plenty of listings online but none in real life. I tried to find and best I found was a set of 3.31
Could really do with a set but may have to fit the 7321-D Spicer I have
Cheers Steve
 

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I think the sterling wud be your only option, but with a lockup converter your likely to be disappointed with that low a gear ratio in anything but a manual trans , those rare 61/71 were made for not overdrive trans (727). So probably not the best combo for modern autos , but stick shift - heck ya-
 

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Discussion Starter #11
Well, I went ahead and pulled the trigger on another donor Dana 70. It is a Limited Slip unit too... Wahoo.

I already have the set of 3.08 Dana 70 ring and pinion and a rebuild kit with bearings. I will cut the carrier and modify the bearings to get the extra offset required. Then install and see if 3.08 is a pig in the "modern auto" that Mercoda warns about. I think it will be okay, but I certainly wouldn't bet the farm. We'll see. If it goes well, then I will hunt 3.08 for the front Dana 60.

I may manual swap this rig in the future, but I like my built auto and it is a big undertaking to change everything out to manual on top of all the other things I have to do already.
I'll try to update this thread when I know the results of my 3.08 swap. Thanks for the help fellas.
Greg
 

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Your main issue is going to be the front axle. I've seen tons of articles about putting lower gears in the Dana 61 but nothing about installing the 3.07 gears from a 61 into a 60. Don't believe it is physically possible so the only choice there is find a 61 axle and change the axles to driver's side drop. Or you might change transfer cases and go passenger's side drop. I looked on ebay and found 1 Dana 70 rear with 3.07 but zero on the Dana 61 front. Going to be an interesting search. Might try some of the Dodge forum sites.
 
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