14 bolt upgrade

[chris989]

Hello all,
I have an 89 v2500. I am going to swap out the 9.5 14 bolt for a 10.5 14 FF. The donor is from a 92 3500
Is there any hidden secrets about this swap i might be over looking. I hate to sound pessimistic but lately it seems everything i touch costs twice as much and takes twice as long.

chris

[andrewmp6]

Since its a different body style truck your probably going to have to move the spring perches and shock mounts.

[chris989]

welding is an easy fix. Knowing GM, I am wondering if i will have metric on one and sae on the other. Things like brake lines. I will crawl under both again and give it a good looking over.

Chris

[Jimbo*]

When you crawl under, break out the tape measure;
If I remember correctly, the wheel mounting surface on a V2500 is 67", and on the 92 model it will be 65". Also, the 92 may well have a D703HD, which is an oddball with 7/8" ring gear offset, as opposed to most D70's 5/8" offset.
The wheel studs should be metric on the 92 rear, and your 89 studs are still standard thread

[greg64]

Jimbo's correct. I researched all this for my 64. There are two different spring pad widths, with the dually axle being narrower, I believe. There is also differences in the wheel mounting surface width. I used a 14 bolt from a 78 3/4 ton, which was a bolt in affair, as far as springs and wheels go. I was trying to stay away from 1 ton stuff, as I remember. The brakes are also considerably different, but any style will work. I switched over to discs in my case.

[BigBlocksRule]

Why the swap? The semi-floater's axles are bigger than the full floater.

[mrolds88]

While the S/F axles may be bigger, they also have to carry the weight of the rig. The F/F axle only has to propel it.

[BigBlocksRule]

^ understood, but I have yet to see a 14-bolt semi-floater torn up.
But I did swap a FF into my 2500 that had a SF, mine were similar years and bolted right up, easy swap. I did it more for the factory G80 than anything else, my SF was/is open and already headed for another project.

[Ziegelsteinfaust]

I swapped in a 14SF into my truck because I wanted a light duty 3/4 ton, but it originally had a 14FF. I had to re-do the mounts, and shock tabs. It was easy enough with a grinder, and a welder. Total time 4 hours. So be carefull which one you buy or mods will ensue.

[Ziegelsteinfaust]

Originally Posted by BigBlocksRule

Why the swap? The semi-floater's axles are bigger than the full floater.

While the SF is a damn good 3/4 ton rear end, and capable of towing 12,000 pounds. The FF will just last under just about any abuse where the SF will eventually eat the outer bearings alive.