2nd Gen Non-Engine/Transmission Switching differentials?

[DDT]

I have a chance to switch my 4:10's for a set of 3:55's. mine is a 2000 4x4 dually, his is a 2001 4x4, dually ( rear disc brakes). I would like a taller road gear my self. Is a swap worth it? How is the best way to do it. exchange axles or just differentials?

 

[Coalsmoke]

Having the 3. 5? in my 5spd, I can tell you that I wouldn't want a 4:10 gear ratio. Actually the 3. 54 is perfect IMO. But that's with a 5spd.





EDIT: I just noticed you also have the 5spd and not the six. If you travel on the highway much, you will deffinetly like the 3. 55

 

[dblake]

Tell him to swap axles and you'll get the rear discs.

 

[DDT]

I do drive 70 most every where I go, My RPM's are at 2400 & the fuel mileage sucks at that speed. I need one more GEAR. He wants to keep his rear disc brakes. I just put $800 in rotors,drums & brakes, new fluid in mine. Can every thing be switched over. I think a axle swap would be easier, any more input.

 

[Big White Beast]

Not sure if I'm reading you here.........

But if I am, the brackets on the ends of the axles that hold the brake backing plates on are different. That is what makes converting to disc brakes such a pain. You'll probably just have to swap gear sets.



Garrett

 

[Mopar_Mudder]

You can't just put the rear disc in their. It also takes different master cylender, proportioning valve and such.

 

[Coalsmoke]

make an appointment at a local rear-end shop, explain what you want to do, and have both you and him show up at the same time. That way they will be switched and shimmed properly.

 

[Dkevdog]

Ditto what Coalsmoke said. Best thing to do is swap axels, but that is not possible so a professionally done orchestrated swap is your best bet. Unless you really, really know what you're doing, its best to let someone else who does do the Job.

Kev

 

[DDT]

Would it be possible to swap front axles & swap rear diff and axles so they match. That way we keep your rear brakes original.



If we swap the whole diff there should not be a shimming hurtle, Am I right or wrong?



I would think we would have to same front & rear axles expect from his disc brakes. or am I way off base here.

 

[Mopar_Mudder]

If you take the carrier and pinion gear out of one and put in the other then yes you MUST reshim and set up the gears. No two axle housings are exactly the same.

 

[Big White Beast]

Still not sure what your asking........

Are you saying you'd want to pull the axle tubes off the pumpkin on the rears?? That would be the only way to get the end brackets for the backing plates the same. Then there would be alignment issues getting them straight & true.



Labor wise your best bet is to just swap gears. If your unfamiliar with the process I would have a reputable shop do it. They should be able to do the swap on both trucks in a day. Cost wise I have no idea.



EDIT: Fronts should be a Dana 70 & rears a Dana 80 on the 3500's. Not positive on the fronts, may be a 60.



Garrett

 

[Coalsmoke]

Cost wise, it will probably be cheaper than having an inexperienced person do and end up having your diff go kaplunk from improper shimming. Also, with 4X4, you'll want to have the front ends matched too (right?)

 

[kah68]

gear and transmission

I am running an 01. 5 with the discs ( they don't work very well, hydro boost ) . I am thinking of getting front and rear swapped to 4:10. I pull heavy 5th wheels and 3:55 are too high with the country i drive in. What i really want to do is find a transmission shop that will take my 6 speed and make it a 5 speed with a 2nd ( Taller ) OD gear in the 6th hole. That way i get those nice low creepy grear and the 5th grear ratio for pulling the big loads up the big hills and the OD2 for running home empty or without trailer. I will be speaking to the transmission shops this week, I hope they can help.

 

[Mopar_Mudder]

Re: Still not sure what your asking........

Originally posted by Big White Beast

Are you saying you'd want to pull the axle tubes off the pumpkin on the rears?? That would be the only way to get the end brackets for the backing plates the same. Then there would be alignment issues getting them straight & true.



Labor wise your best bet is to just swap gears. If your unfamiliar with the process I would have a reputable shop do it. They should be able to do the swap on both trucks in a day. Cost wise I have no idea.



EDIT: Fronts should be a Dana 70 & rears a Dana 80 on the 3500's. Not positive on the fronts, may be a 60.



Garrett

The axle tubes are pressed into the diff housing. This takes alot of effort and equipment to take apart and put back together. That is not a possibility.



Also their hasn't been a Dana 70 in the front of trucks since the 1970's, they are all Dana 60's. Dana 70 rears with an auto and Dana 80 rear with a manual I believe.



Like everyone says just get the gears swaped. Don't know what it would cost, I have always done my own.

 

[Dkevdog]

I was quoted about $275-$340 labor when I was looking.



Kev

 

[DDT]

Are you saying you'd want to pull the axle tubes off the pumpkin on the rears??





What I was trying to say.

The rear diff housing, that you can unbolt from the front of the axle. the gears are still held together by the housing. Could this be switched, and also the drive axles, the axle end that slide into the diff and is bolted to the drum. I may not know what every thing is called. If the drive axles stayed with the same diff then there would still be a match. I will have to look to make sure there are bolts to remove the differencil, I don't think it is a solid casting?

Is my mud any clearer.

 

[lil red cummins]

i think i see some confusion regarding the word "axle" and differential housing. the real question is the "gear" a front loader or back loader design. if the differential is a front loader design, that is, all bolts are on the front of the pumpkin, the swap is a snap. unbolt & rebolt with no worries about shims. the carrier in this design is unitized and independent of the differential housing. if it is a back loader, realigning the pinion to the ring gear will be necessary.

axle swap may or may not be necessary based on whether or not the splines are the same.



does this help?



jim

 

[Big White Beast]

DDT.........

I'm no expert, I paid someone to swap my gears. But I do understand what your trying to say now. Unfortunately I do not believe that our rear ends are set up the way. You have to tear everything apart to get the gears changed.



The carrier also needs to swapped as the speedo and ABS work off a sensor that reads it.



Garrett

 

[DDT]

lil red cummins

Yes that is what I meant to say!!

Big White Beast, If this turns out too confuseing I might have to call a pro.

 

[DDT]

OK guys, if this is done it will be done by a pro. Do I need to change my seed sensor since I have 4:10 & going to 3:54?