Swap 8.5 IFS for 9.25?

[Supercharged111]

I imagine if this were a simple bolt on I wouldn't be asking in the first place. I have a K1500 and a K3500 and just to eyeball them they sure look interchangeable. I dug deep into the bowels of the google years ago and found 1 person that did it, but of course when I found it none of the pics worked and at this point I don't remember what he did to make it work. Has anyone here done it? Am I full of ****?

 

[884x4310ci]

I did just read on another forum of a guy that did it. By his word there's only one mount that is not at the same place.
plus you have to take 3/4ton inner and 1/2ton outer for the cv shafts.

 

[camaroman101]

Pkiser0993 is the guy that did it

http://www.gmfullsize.com/threads/97-k1500-8-25-ifs-to-9-25-ifs-swap.209002/page-2

http://www.gmfullsize.com/media/albums/my-z71.6360/

& info pics about the CVs
http://www.gmfullsize.com/threads/u...ked-aam-9-25-with-hydro-assist.215119/page-12

 

[Supercharged111]

That all sounded familiar but I never remember seeing pics. One issue I see with swapping in 8 lug knuckles is the difference in height, but if a guy were to drop those lowers a smidge it'd all work real nice. When you figure I can snag these from the junkyard for under 100 all day it becomes an appealing swap IMO.

 

[98chevy2500SS]

Reading this thread after I had been talking about it on BowtieBrody's truck thread, thanks for the links @camaroman101!!! These were helpful, makes me have hope in my swap to 3/4 axles!!!

 

[camaroman101]

Reading this thread after I had been talking about it on BowtieBrody's truck thread, thanks for the links @camaroman101!!! These were helpful, makes me have hope in my swap to 3/4 axles!!!

No problemo, if you guys do it post plenty of pics! Then maybe I'll have the guts to do it.

Found one more link with useful pics and info from the same guy, Pkiser0993. I'll add it to my first post also.
http://www.gmfullsize.com/threads/u...ked-aam-9-25-with-hydro-assist.215119/page-12

 

[Supercharged111]

Below is the gist of what he did. For being the only documented one, you'd think he'd have done a better job with pics and whatnot. Sounds pretty painless. I think I wanna do the NBS brake swap 1st. And hydroboost. And a bigger blower. And a lift.

I do use the 9.25 axles....that's what I shortened. New 1 ton axles ran me $70 at O'Reillys auto part. Like I replied to davkenrem....did have to shorten the diff top hanging bracket as well....so to sum it up....all the mods I had to do to get the 9.25 IFS installed with 1 ton axles are: (1) Shorten top diff hanger bracket to clear steering drop down bracket. (2) Use original A Arm bracket from 8.25 diff and ream out bottom whole a bit to except bolt. (3) Shorten each CV axle by 1" of which I described already how I did that. Am looking to install my rear locker this weekend and run the trails at Hidden Falls OHV park on January 31 to test rear locker as I have already been there and tested front locker. Keep in mind you only need a welder and a some sort of metal cutoff tool plus a carbide reamer to accomplish this plus about a day or day and a half. Also keep in mind the type of lift you have on truck. I have a Rough Country 6" suspension lift and these are all the mods I had to do for it to work. Depend on the geometry of other lifts there could be something else. I have found the some look the grind down the cooling/structural fins on the pinion shaft part of the diff housing to make it fit in the lower diff mount.....avoid this if at all possible as it is a "structural" part of the housing itself. Almost forgot....had to shorten the front slip drive shaft just a bit ...$35...no special yoke was needed to match up as the U-Joints on the 97 K1500 and K3500 are the same. All in all for rebuilding the 9.25 with all new parts and locker plus drive shaft work I have about $1200 in the conversion....$806 was for the Locker alone.

 

[98chevy2500SS]

I would say the IFS swap is cheaper than the SAS swap, that's what so great about it and you have the comfort of the IFS.

Since I got my IFS 3/4 and rear axle for free from a guy, that will make my job much cheaper!

 

[Supercharged111]

I like the idea of a locker up front and out back and not worrying about either one exploding.

 

[98chevy2500SS]

I did find out that the mount that is not in the right place for this swap is the front mount. There are two mounts in the front for the IFS, the front one is the one that needs to be cut. The bottom should fit in, and torsion bars will fit in. That's what I know at this point. I will be sure to let you guys know how it went and what's involved with this. Going to start this in a week or a few weeks. I also do know, you will have to have the steering aligned and the tires aligned to be flat on the ground.