Im buying Moser axles for my 85 IROC, and I was wondering if it hurt anything to buy the 28 spline axles and all the rear end parts for 28 spline. Everywhere I've read it says that 28 is for 88-up, im just confused and wondering if someone could help me.

 

Your signature says you already have 28 spline axles ?
Why do you want to replace your axles ?
If your running 4.10 ratio. then you already have the 3 series carrier,so your saying you have a 26 spline 3 series carrier with 26 spline axles and want to upgrade to 28 spline axles and everything that gos with it.
If you want to upgrade to 28 spline there is allot that will need to be replaced.

1. master bearing kit = $ 90.00
2. axle bearings and seals = $ 30.00
3. 28 spline axles = $250.00
4. installation/labor = $ 300.00
5. You will need to upgrade to a 28 spline carrier and this is what I found in a Detroit Locker.(a direct replacement for the one you have.)= http://www.ebay.com/itm/Eaton-Detroi...orcev4exp=true

(A few 89s received 28 spline at the end of there production run but it was "90" that 28 became stock.)

 

Depends on what else you're buying.

28-spline axles won't spline up to 26-spline side gears.

You can't just put 28-spline side gears in your carrier, because the axles won't fit through the hole in the carrier. Well, maybe I shouldn't say that... you CAN put the gears in, you just can't assemble the car.

If you're buying a carrier anyway, no reason you can't put in both a 28-spline carrier and 28-spline axles.

Don't.

I'd suggest these axles here instead of the Moser ones. http://www.summitracing.com/parts/SAG-EV10-4/ Save the "custom" axles for a "custom" situation. For a stock setup though, the Superior ones are made in the correct order: metal is soft, splines are ROLLED (not CUT like the "custom" makers), then the finished product is heat-treated to fully harden them. "Custom" axles are made from metal that's already mostly hardened, but isn't heat-treated (which takes a couple of weeks) afterwards; that's how they can offer fast turn-around on your order. Same price, better product for a stock replacement application like this.

Moser is a perfectly good product, for what it is, and what it's intended for; this simply isn't the right place. It's about like putting Richmond drag race gears in a car that will EVER see the street. Not that they're "bad", just, not the right match of part to application.