1/2 ton to 3/4 ton Suburban axle & suspension swap

OK... I am new here and this is my forst post. I have a dilema.
I have a '89 1/2 ton Chevy Suburban 4x4 with a really bad problem in the front end. I am thinking of trying to put 3/4 ton axles on it.
I may be getting a '80 Chevy 3/4 ton Longbed pickup.
If I buy the pickup can I swap the springs and all over or are they different? Something tells me they are gunna be wider as well as thicker.
Will I need to get different U-joints when I rebuild the drivelines? I think in the parts truck it is still a 10 bolt in front... I hope it's a 14 bolt in the rear. In my Suburban I have 10 bolt front and rear.
I know my truck won't really be a 3/4 ton, but I just need stronger axles for towing. Especially the rear. I figure I had the same rear end and gear ratio (3.42)in my '78 camaro.... aint worth a crap for towing as far as I'm concerned.
I've already been told to upgrade to a 3/4 ton master cylinder and steering gear. I was told that won't be an issue to use the steering gear off of the parts truck.
Will I need a special pitman or steering arm?
Anything else you can say to help is greatly appreciated.  

the stearing is easy to upgrade and the 3/4 ton chevy will have the same front axle as your 1/2 ton probably a Corp 10 bolt with larger brakes and diffrent gears. and its probably an 8 lug. the springs and rear axle should swap out as well as the front axle. make sure you keep your ratios the same in the front and rear.  
[X] Give Er Hell [X]

ooh, yeah... I'm 100% sure the gear ratios match.
You are correct about the front. I hope we're correct about the rear springs. If not I'll have to either modify the shackle hangers to make them wider or just use the axles... people are telling me that the mount plates should work.... but noone is 100% about the springs.
I do know that when looking into lift springs the kits have 1/2 ton or 3/4 ton in the description... That dosen't mean much. They might just use narrow springs and bushings to make them fit the shackles.  

They will swap out with no problems as far as the spring mounts gofront and rear. The reason the springs are 1/2 or 3/4 is because some have the longer springs on the 3/4 models. I've done this to all my 1/2 Ton trucks and Blazers I've built in the past. Its easy to do.  

As you already know, you will not be gaining anything as far as strength by swapping the front ends, just simplicity of having 8 lugs all the way around.  Yes, 3/4 ton springs are usually longer than 1/2 ton springs.  That is not why the manufacturer asks 1/2 ton or 3/4 ton when buying a lift though.  When most people buy a 4 or 6 inch lift for these trucks (the most popular sizes), they do not pony up the extra $ for replacement rear springs.  They just buy the cheapo package that's advertized in every magazine on the planet and those all come with rear blocks.  When using rear blocks, it doesn't matter what length springs you are using.  The reason for asking 1/2 ton or 3/4 ton is so that the consumer gets the proper sized U bolts.  The Corporate 14 bolt has much thicker axle tubes than a 10 bolt or a 12 bolt does.  Therefore, the manufacturer or retailer needs to know what rear axle you have.  1/2 ton u bolts will not fit around that big 'ol 14 bolt's tubes.  Just another piece of advice, ditch that 10 bolt front axle and get an 8 lug Dana 44 if you can't afford to put a Dana 60 in it.  

lol...... there is really no proof a front danna 44 is stronger than a front 10 bolt.... their basically the same axles....the only upgrade would be a dana 60......all the springs fit fit only thing that might need adjusting is the spring mounting perches on the axles but thats it...  
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Geo, I never said anything about the 44 being stronger than a 10 bolt, that arguement has been beat to death with no clear victor thousands of times.  Strength issues aside, there is no room for argument, however, that the aftermarket supports the 44 much more than the 10 bolt.  Plus, if he ever decides to switch to crossover steering, chances are good the passenger side knuckle will have a flat top already milled into it.  So, please make sure you truly understand what someone is stating before assuming something different.  On a side note, how do you like that 700R4/208 combo in your rig?  I'm getting ready to do the same thing to a 77 K5.  

WYJAX:
Geo, I never said anything about the 44 being stronger than a 10 bolt, that arguement has been beat to death with no clear victor thousands of times.  Strength issues aside, there is no room for argument, however, that the aftermarket supports the 44 much more than the 10 bolt.  Plus, if he ever decides to switch to crossover steering, chances are good the passenger side knuckle will have a flat top already milled into it.  So, please make sure you truly understand what someone is stating before assuming something different.  On a side note, how do you like that 700R4/208 combo in your rig?  I'm getting ready to do the same thing to a 77 K5.

well it seemed like you were implying that strenght was a factor....... but your right on the d44's extra support..... how do i like my 700r4/208 combo well here goes: i really like the 700r4s deeper first gear, you can tell its deeper compared to my old th350, the low range in the 208 is way lower then the old 203 or 205 cases so it helps out for slow crawl situations.  i just recently put in the 4:88s and let me tell you with those gears and low range that truck wants to twist itself off the chassis!  it pulls really good in low range and with the lower gears i can actually use overdrive so yeah  i like my combo better than the old th350/203 combo  
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