Dodge Truck

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carfreak6970

carfreak6970

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Hello Folks!

I know this isnt an A-body, but I hope some owners here will be able to help me since this should be a common swap:

I have a 1990 Dodge W150 that I would like to swap in axles & springs from a 3/4 ton Dodge. What do I need to make this happen? and what donor vehicles should I look for?

I heard something about the earlier dana axles being different from the later models, is this true? would the newer/more common axles fit? would I be able to swap out the gearing if I chose to do so?

I believe this is the electronic Speedo, since these axles would be changing the gear ratio, how do I get the speedo to read correctly? is it a simple gear swap like the old 904/727? or is there something else?

With swapping out the axles, what would happen to the brakes? would the backing plates out I have now still work with the heavier axles? Would the front brakes still work? Would I need to upgrade the proportioning valve/master cylinder? What about the brake lines?

Currently the truck has warn hubs up front, I would like to keep that feature. Would these swap over to the new axles? or would I have to get different ones?

What would this do to steering up front? Would I need new linkages and such? anything else change with the steering? like steering gear and pitman arm?

How would this affect the 4 wheel drive system? Would I need to change out any hardware or controllers for this? could this all bolt up to the transfer case I have in there now? (id really not want to change the transfer case...)

Would I need to shorten/lengthen the drive shafts? Or would it just be better to get the drive shafts out of a 3/4 ton gas truck? I am assuming the drive shafts may be different for the diesel truck?

Would doing this swap affect the ride height? I am not running a lift kit (its at its factory height currently), I dont want to run a lift kit - I only have a couple inches between the garage ceiling support beam and the top of the truck now, not trying to push it.

Thanks
Joe
 

Most all 3/4 ton trucks still used the Dana 44 up front. It's not till the 1 ton does it change to Dana 60.Stay away from the 1975-1979 as they were full time front axles and had a poor front hub/bearing design. I built a 1980 1/2ton and used Dana 70 front and rear with no major issues. The front end was a closed knuckle design. Both had 5.13 gears which worked out good with 44" tires.
 
I installed Dana 60 axles both front and back on my 89 Dodge short box 1/2 ton several years ago. I will share with you what I remember.

The axles will bolt on no problem but I recommend new u-bolts and nuts. Just cutting the old u-bolts and putting it back together with new ones is a huge time saver. The u bolts are under some stretch though and they will pop open when cut. If you are using Dodge axles then you should be ok with the shock plates and spring plates from the 1/2 ton.

I'm not sure about older to newer Dana axle differences but my rear diff was a D-60 from a 78 Dodge 2wd 3/4 ton and it was a direct bolt in affair. My front D-60 was from a single wheeled 1 ton Chevy and the spring perches ended up a 1/2 inch wider than the dodge ones but with my lift springs I didn't even notice this until someone told me about it later. If you stick with a Dodge axle it will definitely be a bolt on affair too.

The electronic speedo sensor is driven by a gear the same as the cable driven ones are so it would make sense that changing the gear in the trans would have the same effect as it does on the cable system. I never changed mine.

I used stock Cummins brake calipers and rotors on the Chevy front diff and they hooked up to the factory rubber brake lines no problem. The rear 78 3/4 ton brakes connected the same as the factory 1/2 ton brakes did. I left the hard lines on the diff alone and purchased a new rubber line to go from the diff to the brake line on the frame. My stock booster and master cylinder stop the truck just fine with no change to the proportioning valve but I will look into upgrades here out of curiosity. Likely stock 3/4 ton or 1 ton booster and master cylinder.

My D-60 front came with locking hubs that I reused. Your 1/2 ton D-44 locking hubs definitely won't work on a D-60 and likely not on an 8 lug D-44 either. Just make sure there is no CAD system on your new diff and can add locking hubs to it. Remember if you buy a diff from a full time 4x4 truck you will almost definitely need to swap everything from the knuckles out to get locking hubs. I say almost because I had a buddy that had a factory original 3/4 ton full time 4x4 with a D-60 that utilized conventional bearings and hubs with drive flanges. The drive flanges can be swapped for locking hubs.This was very rare from what I am told. As said before, the unit bearing style full time hubs are not real good especially in a part time 4x4 truck.

I got a new drag link and tie rod but it connected to the stock 1/2 ton steering arm. I actually think the stock drag link could be reused too but I can't remember that detail.

No need to change the transfer case. You can remove the vacuum harness for the CAD system since you won't need it anymore. Also the 4x4 engaged light will no longer work as it was switched at the CAD actuator. I reused my front driveshaft as a bolt in deal with the addition of a different yoke on the front diff to accept my smaller 1/2 to u-joint. Someday I will likely upgrade to the larger joints like the Chevy D-60 came with but it has not caused me problems so far. The rear bolted together exactly as it came apart. In your non lifted application you may experience problems with driveshaft length in the front if changing from D-44 to D-60 or in the back changing from 9 1/4 to D-60 however I did not.

The only difference in ride height may come from a difference in tube diameter between the old diffs and the new diffs, or possibly the tire size because you will need 8 bolt rims, and 15" 8 bolt rims (at least the ones I tried) require way too much caliper grinding or humongous wheel offset. I don't know how tall of tires you have now but you will need at least 16" rims so you may not be able to get the same size rubber for that as you have on your 15s. The change would be minimal.

I am a big fan of this 3/4 ton or 1 ton axle swap because you get better brakes and usually better gearing and they can be found relatively cheap if you look long enough. I got both of my D-60 axles for free 10 years ago and all they really cost me was the new brake parts that I installed. They have 4.10 gears that really helped with my bigger tires.

I hope this helps. These are my first hand experiences and others may have different results.

Cley
 
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SGBARRACUDA said:
Stay away from the 1975-1979 as they were full time front axles and had a poor front hub/bearing design.
Click to expand...
what happens if you have a '77 full time (ramcharger) and you take a mid 80's ramcharger complete front axle and put that in? is it a direct swap? or should the mid 80's transfer case be used also? I see a lot of them with lock-outs. thanks
 
I would keep your front diff and swap everything from the C's on the diff tubes out with the 80's Truck or Ramcharger parts. If you want to stay with full time 4x4 then just use the metal slugs that are installed in place of the locking hub on all the CAD trucks. These slugs are splined to the axle on the inside and the hub on the outside so they positively lock the hub with no chance of slippage. It is a better cheaper bearing design. It will however convert you to 5x5.5" bolt pattern in the front. Swapping the rear to this bolt pattern only requires drums and axles from a donor truck.

If you decide to swap to a part time transfer case, the same can be done to the front diff, but you can use locking hubs to replace the metal slugs. Then with the hubs unlocked, only the rear driveshaft spins when in 2 hi.

Just a note that you likely already know, If you use the locking hubs with the full time transfer case, 4hi and 4 lo will be useless with the hubs unlocked. You will go nowhere due to the differential action within the transfer case. Hi lock and lo lock would work as 2wd with the hubs unlocked but the front driveshaft and diff would spin with no power being transmitted to the wheels because of the unlocked hubs.

Cley
 
I have a 87 w150, never dealt with axles but I know springs are fairly simple. Mine has a dana 44 in the front, 3/4 springs swapped over with no issues other than u will need longer studs on the passenger side (pass side has 1 u bolt and 2 studs), my u bolts were long enough and I re-used them. Hangars are the same on front atleast for my 87, Haven't put my rear springs on yet but i'm pretty sure all you would need would be the 3/4 hangars, and everything should bolt up. My rear is a 9 1/4 to the best of my memory. There's a thread on for trucks only i posted about the rears ages ago, ill try to find it when I get off work. Also the bushings are the same for 150 and 3/4 springs, once again atleast for my year model. I have the moog part # at home if you need it. If you need pics of anything on mine just lmk.

As far as lift, my front 150 springs were sagging (especially drivers side), got the 3/4 springs to correct that, it didnt lift mine very much at all, just corrected the horrible sag and drivers side lean the old ones had. The front is barely higher than the rear, hard to notice, but my current rears are strong. Mine is stock lift on a 31.5 tall tire.
 
Thank you for the suggestions folks!!

Cley, You bring up a lot about the CAD system, what is this? When i was looking at LMC truck they have something in there for the CAD system. would my 90 W150 have it? Would CAD be the first gen trucks part time set up, and the non CAD be the full time set up? Or is that vice versa?

I was planning on trying to find a 91-93 W250/W350 for the axles if that matters.

I guess if the bolt pattern changes, the brakes would need changed. So ultimately, but try and find the axles with the brakes and springs still attached and I should be golden?

and BigBlockMopar28, I would appreciate that information if you can find it. I would like to know what to get before I start looking and buying things.
 
carfreak6970 said:
Thank you for the suggestions folks!!

Cley, You bring up a lot about the CAD system, what is this? When i was looking at LMC truck they have something in there for the CAD system. would my 90 W150 have it? Would CAD be the first gen trucks part time set up, and the non CAD be the full time set up? Or is that vice versa?

I was planning on trying to find a 91-93 W250/W350 for the axles if that matters.

I guess if the bolt pattern changes, the brakes would need changed. So ultimately, but try and find the axles with the brakes and springs still attached and I should be golden?

and BigBlockMopar28, I would appreciate that information if you can find it. I would like to know what to get before I start looking and buying things.
Click to expand...
Will do, i'll post when I get a chance
 
CAD is "Central Axle Disconnect". After about 1984, Dodge started using a vacuum actuated sleeve on the long tube of the front differential. When shifting into 4x4 a vacuum motor would slide a collar over the split in a 2 piece axle locking the 2 halves together. I don't know which 3/4 ton and 1 tons have it but your 90 1/2 ton will. It actually works ok but I don't like the idea of the added complexity. That is why using a full time axle with CAD axle outers is a good idea because you get a 1 piece long side axle and its easy to add locking hubs.

Cley

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Bushings are Moog SB266 (front), and SB268 (rear). I found the old thread too. Those guys said to use new u-bolts, shackles, etc. I personally re-used shackles, hangers, and u-bolts in the front, the only new thing was the 2 passenger side bolts because they we're too short, granted mine was in very good condition. Not sure why hangars and shackles would need to be replaced if they had no previous issues anyways... springs eye bolts were the same and the old hangars and shackles I got from the w250 were the exact same on mine so I left the old ones on the truck and just swapped springs. Haven't gotten to the rear on mine as previously stated but eye bolt size and spring width are the same from 150 to 250 in the rear so I dont see why shackles/ hangars would be any different.

If you want some pics of my setup i'd be happy to send, pretty sure I took some before the front swap.
 
318willrun said:
what happens if you have a '77 full time (ramcharger) and you take a mid 80's ramcharger complete front axle and put that in? is it a direct swap? or should the mid 80's transfer case be used also? I see a lot of them with lock-outs. thanks
Click to expand...
Well the difference is the full time 77 will have a full time NP 203 transfer case and is chain driven. If you put part time axles with the 203 your front shaft will turn all the time. And If I recall you would have to shift it to 4WD lock to drive the truck. They did make a conversion kit for the 203 but I never liked the chain drive. Your 80's will be either a NP 205 or the later uses the aluminum 208.
 
SGBARRACUDA said:
Well the difference is the full time 77 will have a full time NP 203 transfer case and is chain driven. If you put part time axles with the 203 your front shaft will turn all the time. And If I recall you would have to shift it to 4WD lock to drive the truck. They did make a conversion kit for the 203 but I never liked the chain drive. Your 80's will be either a NP 205 or the later uses the aluminum 208.
Click to expand...
so your suggestion would be a front axle with lock outs and the transfer case from a mid 80's ramcharger?
 
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