You will need a carrier for both axles to use the larger gears. There is no doubt that the stock replacement 3.73-higher carrier will be stronger than the 3.42-lower carrier you have in there now is considering what you are proposing. You will likely have problems with the ring gear bolts if you stay with the current carrier with those large tires.

Your next problem is going to be the axle shafts themselves. 40" tires are quite a bit over what the 10-bolt front and 12-bolt rear axle can handle aside from light offroading. Start bouncing around or really using the low range in your transfer case, and you will start snapping axle shafts.

You really have to ask yourself how you are going to be using your truck. If it is just for light offroading and you like how it sits, then you can stay with what you have for axles and update the gearing. But now is your chance to upgrade the axles at the same time. A Dana 60 / 14-bolt full floater combination would be exactly what you need with the power and tires you currently have.

 

Ok. i'm still kind of confused what the carrier actually is.. I mean you mentioned they didnt cost to much but I found that Dynatrac Pro 60's, kinda like what you mentioned cost upwards of $4000 each!! - thats an entire axle assembly though, this is where I'm confused, is this what I should be looking for...

http://dynatrac.com/products_gm_6891faa.html

*Say I do decide to go down the " A Dana 60 / 14-bolt full floater combination" you mention, what do I need exactly to reach this target.. So theres the carrier? The new gears? What else? Any chance you could supply a link to the sort of thing i'm looking for... Sorry about all this but Thanks in Advance.

 

The carrier is what the ring gear bolts to. It is the differential housing itself, not the axle tube/pumpkin though.

If you decided to go with a Dana 60 / 14BFF, that would be a complete replacement front and rear axle. You would need to change to 8-lug rims as well.

 

So if I changed the carrier, i'd retain my current axle shafts and hubs. What about the drive shafts? Now you say this is my cheapest option but i might end up wrecking an axle shaft if i put them under any heavy duty?

My alternative is to upgrade to heavier duty axles such as 14 bolt/ dana 60's and in this case I'd have to go for an entire axle assembly such as the link I posted above? Now i'm guessing that dynatrac are an up market make so who could I go to for a cheaper alternative? Would another option be to go to a scrap yard and see if i can find a 75 - 91 heavy duty chevy and take the axles from it?

 

Go used, not new! Much cheaper. You can typically find a D60/14bff combo for under a grand. If the 14bff comes out from under a 1ton pickup, you will have to move the spring perches in. If it comes out from under a 3/4 ton pickup, it'll bolt right in.

My free 14bff (by virtue of me stuffing it in the woods 13+ years ago when we cut it out from under one of our farm trucks):

My $30 3/4 ton 10-bolt for the 8-lug conversion parts to use on one of my D44's until I can find an affordable D60:

The 10-bolt also comes with the fulltime 4wd inserts in the hubs which I'll keep for the eventuality that my lockout hubs break while offroading.

 

Ahh got ya, now this is all coming together.
Thanks so much.
What are spring perches though? Easy job or not?

 

I call it easy, but I have everything to cut off the stock perches and weld them back on in my garage.

 

Hey Kyle.
So i've been thinking about this gearing thing alot, the last few days and call me crazy but for time and money, i'm considering going with the 4.56 gears for the 3.73 and down carrier. Mostly this will be to get me through winter, I won't be doing any wheeling, it'll be 95% on road and maybe 5% playing in the snow. I understand what you say about it pushing the pinion far away from the carrier but based on my usage will this set up be ok for 6 months max. while i get some money together after xmas for a whole new set up with 1 ton axles?

Also when I change to the new gears, should i buy the complete overhaul kit that includes new bearings and all that. Couldn't hurt right?

Thanks in Advance.
Jamie

 

It is your money. The carriers are cheap (<$50) so that should not prohibit you from getting the proper carrier.

You may want to keep your eyes open for some used gears. I bought a set of 4.10 gears for my D44 and 14BFF for $100 delivered and they look almost new.

If you keep your eyes peeled, you can probably find a set of 1ton axles for less than the gears you are looking to buy now. Remember, you have to replace both the front and rear gear set if you want to keep your 4wd functional.

 

Yeah thats a good point about the carrier. Ok so i'll likely get a carrier and the proper gears for it. About fitting, could a guy do it in his garage? Do the axles need to be dropped or will I be able to do it just from taking off the differential cover?