Okay so maybe y'all can help me I bought a 2500 rear end put in a k1500

[99xcss4]

I think it is this one if it is not complete it is nearly there. https://www.gmt400.com/threads/9-25-ifs-conversion-0-3-lift.60583/#post-1284970

 

[99xcss4]

I think it is this one if it is not complete it is nearly there. https://www.gmt400.com/threads/9-25-ifs-conversion-0-3-lift.60583/#post-1284970

I have another one https://www.gmt400.com/threads/k1500-8-25-to-9-25-swap.56989/

 

[62barsoom]

#45 put an end to that idea. So if I can fund it next year re gear and a locker in the rear. The tow package gave me the bigger brakes. The Suburban has spoiled me with the Hydro and 800 steer box. Pulling those 3 mods off would be nice. This isn't going to be in the mud but 7 and 9% grades abound here. Add a trailer full of firewood and I'll want the grunt.

The issue with the big tires and mud running is going to be the CV joints.

That's your weak link.

The rear axle will swap a 14 bolt Semi or Full floating axle with little more than spinning wrenches. Good luck popping a 14 bolt full floater. I've seen it done, but it takes some serious abuse. Nothing a TBI 350 can put out....

The larger 2500/3500 front diff (9.25 vs the 8.5) will not go into a 1500 frame without modifications. You will need front diff/suspension drop brackets or some serious grinding and cutting on the bigger diff. Sometimes both. Then there's the rest of the suspension to deal with: track width, mount points, etc. The 2500 front suspension won't just bolt on either. The lower arms will go in, but the upper mount geometry and the bracket placement is different. Mixing 1500 uppers and 2500 lower won't work either. You either have to do something with custom length cv axles or cut and weld the upper A arm brackets.

You do not want to cut and weld the upper A arm brackets. Trust me, you don't.....

The big plus of the bigger from diff is you can run the bigger 2500 CV's. They're not a lot stronger than the 1500's, but stronger. As long as you keep the lifts low and the shafts fairly flat, CV axles hold up fairly decent.

The other big plus for the 9.25 front diff is you can actually buy a locker for it. Nothing available for the 8.5. locking up the front in deep mud is a must IMHO. If you are talking serious mud it is, if you're talking splashing around in puddles then don't worry about locking it. Problem is; when you lock it up, you're putting more stress on the diff. If the axles don't pop first, you might pop the 9.25. That takes serious abuse, but it can be done. Eh, the CV's usually "go on vacation" first....

There was a thread (on pirate 4x4 I think) about modifying 2500 CV axles to fit a 1500. You might want to see if you can dig that up. Word of caution: don't say you're building a GM IFS over on teh pirate board. You will get flames 6 different ways to Sunday.....

There are custom front CV axles, but they are uber bucks. As in: take your purchase price and multiply by 3....If I remember, that will buy you one axle....and guys even pop those mud running.

38's are little big for any CV axle though, no matter how you slice it. The IFS is not designed to handle it either.

Take away points:

keep the CV axles flat as possible.
Minimize turning when hammering it
Be ready to replace CV axles/parts with big wheel speed and hitting buried stumps/rocks/solid ground.

Cheers

 

[62barsoom]

#45 put an end to that idea. So if I can fund it next year re gear and a locker in the rear. The tow package gave me the bigger brakes. The Suburban has spoiled me with the Hydro and 800 steer box. Pulling those 3 mods off would be nice. This isn't going to be in the mud but 7 and 9% grades abound here. Add a trailer full of firewood and I'll want the grunt.

Sorry I'm to tired to be on here. I thought I was posting to my build thread. Long day, too little sleep.

 

[Schurkey]

putting a 2500 rear end in a k1500

WHAT AXLE is coming out? The usual K1500 8.5" ring gear disaster?

WHAT AXLE is going in? C2500 or K2500? They're different. 6-lug or 8-lug? 9.5" ring gear, or 10.5" ring gear?

can anybody tell me what all needs to be done

No. Not without more info you should have put in your first post.

The simplest possible way this works out is for you to buy four U-bolts, nuts, 'n' washers of the correct size, and a conversion U-joint, Precision 447 or equivalent.

The 8.5 axle comes out by pulling the brake hose at the axle, the shocks at the axle, the driveshaft, the axle vent hose at the frame/bed and--the worst part--disconnect the park-brake cables. Then cut the U-bolts.

So we're clear--this all assumes that the brake and vent hoses, and brake tubes at the axle on both axles, the shocks, and the park brake cables are still in good, usable condition--and they're often not. Fair chance you'll need new brake cables and new brake tubing from the wheel cylinders to the brake hose.

The 9.5" six-lug K2500 axle goes in using the larger U-bolt plates from the K2500 donor vehicle. Shocks and brake plumbing bolts right up, as do your existing wheels.

But if you don't have a 9.5" axle, if you don't have a 6-lug axle, if you don't have a K2500 axle AND the U-bolt plates...thing are going to get messy.

and free floating gears

I have no idea what that means.

Please, organize your thoughts, use punctuation, and proofread before you hit that "Post reply" button.

THANK YOU.

 

[GoToGuy]

Really, before you throw money at parts, do a little research.