2000 Gmc jimmy SAS -- need advice !!
 

i have a 4 door 2000 jimmy its got a 2.5'' rough country and were deciding to do a sas on it. ive done alot of researching but theres still some stuff i dont know, i was thinking dana 40 or 44 for the front and im buying a leaf spring mount kit so thats settled. one thing i dont get is can i run a dana 40/44 and just re gear my rear axle to match? it seems like everyone is doing rear axle swaps too..
and after that my only concern is steering, ive read of people using the chevy astro steering box? with a jeep pitman arm? any help would greatly be appretiated, my idea was to buy a jeep axle for the front, and a 373 chev axle for the rear or just re-gear, run leafs up front and a custom drive shaft.

thanks!!!!

There is no such thing as a Dana 40 only a 44. There are many reasons to swap the rear axle starting with strength, width and lug pattern. Simply saying you want to buy a jeep axle isn't really giving any useful info to add to sorry. The most common jeep axle used is a wagoneer axle. If your buying a hanger kit your limited to axles with a 32.5" spring pad width or the ability to make them that width. I'm not sure what you mean buy a Chevy 373 axle (gear ratio?) The astro box is only necessary depending how far you move your axle forward.

Honestly my suggestion to you is to spend a few more months researching before you even buy a single part so your not spending money on parts that aren't going to do you any good.

yeah I meant 373 gear ratio, ive done more research and since I'm only doing 33s I've decided to go with axles out of a jeep Cherokee so dana 30 and 8.25 rear, gunna do leafs up front to keep it simple with the ORD leaf hanger kit, about the astro steering box does it just straight up swap out for the stock one or is there modding to do? and my last question is about driveshafts to go from my stock tcase to my front dana 30

im getting close to starting kinda soon but im seeing that people have to modify the stock exhaust y pipe to fit a sas, is that true?

Yes, the exhaust coming from the drivers side manifold interferes with the driveshaft. You can get a y-pipe from a 2wd or modify the stock one.

By more research I meant like a month or two of taking every spare moment you have to read every build thread that you can find involving an SAS not just an extra day. The questions you are asking are all covered a million times on the web. I am not saying this to be rude so please don't take it that way I truly am just trying to prevent you from getting started and realizing you don't have everything you need or the knowledge you need to complete the swap and end up with an unfinished vehicle sitting around forever.

You likely won't need an astro box if you are staying low with small tires because you won't need to push the axle forward for clearance. You can swap the front output yoke from a jeep xj and run a modified xj front shaft your a driveshaft. For the rear your stock shaft will work fine with a conversion joint. Yes you will either have to modify your y pipe or run a 2wd pipe like Jam stated.

If I could suggest a much better axle combo as well as being the wagoneer 44 front with a rodeo 44 rear. You will have to purchase them separately but they will have matching lug pattern, correct width, the front already has the spring perches in the correct location (the front 30 you are talking about does not as it is a coil spring axle), you can easily find the rodeo 44 with a factory locker and if you can find two the locker will swap into the wagoneer axle as well for cheap lockers front and rear. Not to mention this combo will be far superior in strength over a 30/8.25 combo which is pretty much comparable to what you currently have under your truck.

Remember its your truck and you can do as you wish but you asked for help so thats what I'm doing:)