crazykaese
91ProtoTy/IndyPaceTribute & Sawzall Master
Are these just stock replacements for our stock rears or are they an upgrade? What is original for our trucks? I'm rebuilding/replacing mine soon and would like to upgrade while it's apart.
28 Spline Axles
- Thread starter crazykaese
- Start date
'JustDreamin'
Dream: 6LV8 Turbo Bravada
Re: 28 Spline Axles
The two available spline counts for the 7 1/2" & 7 5/8" (they're pretty much the same axle) are 26 and 28 spline. The 28 spline is marginally stronger (I wouldn't exactly call it an upgrade). And, the carrier (limited slip or whatever) must match whatever spline count you have. So, if you've got 26 spline and want to change to 28, you need the axles AND a differential / limited slip / locker / spool.
The axle spline interface itself isn't necessarily the weakest point. Pretty much, the design isn't big enough (size wise) for most of the applications its in. Like the 93 to 02 Z28. Those cars all came from the factory with pretty stout V8's and a weak rear. And the axle was originally designed in the 70's for things like 4cylinder Vega's and the like.
The single biggest problem with the rear is the fact that it is unpredictable. Some of the camaro guys run deep into the 10's on the stock axle with manuals. Others break them with stock motors and autos (running 13's and 14's) and street tires. Almost seems like playing roulette.....And the winner is: Green 00.....If it was consistently good to a certain point (consistently good to 475hp) at least then you'd have something. But its not consistent. Maybe it has to do with what day of the week they were built on.
If you're looking to upgrade, don't bother with just axles. Upgrade the whole rear. The 8.5" 10 bolt was available in manual trans V6 S10's starting in '95 or '96 or so. They're around, but not all that plentiful (can even be had with disc brakes). Or you could step up to a 12-bolt / Ford 9" / Dana 60......
'JustDreamin'
The two available spline counts for the 7 1/2" & 7 5/8" (they're pretty much the same axle) are 26 and 28 spline. The 28 spline is marginally stronger (I wouldn't exactly call it an upgrade). And, the carrier (limited slip or whatever) must match whatever spline count you have. So, if you've got 26 spline and want to change to 28, you need the axles AND a differential / limited slip / locker / spool.
The axle spline interface itself isn't necessarily the weakest point. Pretty much, the design isn't big enough (size wise) for most of the applications its in. Like the 93 to 02 Z28. Those cars all came from the factory with pretty stout V8's and a weak rear. And the axle was originally designed in the 70's for things like 4cylinder Vega's and the like.
The single biggest problem with the rear is the fact that it is unpredictable. Some of the camaro guys run deep into the 10's on the stock axle with manuals. Others break them with stock motors and autos (running 13's and 14's) and street tires. Almost seems like playing roulette.....And the winner is: Green 00.....If it was consistently good to a certain point (consistently good to 475hp) at least then you'd have something. But its not consistent. Maybe it has to do with what day of the week they were built on.
If you're looking to upgrade, don't bother with just axles. Upgrade the whole rear. The 8.5" 10 bolt was available in manual trans V6 S10's starting in '95 or '96 or so. They're around, but not all that plentiful (can even be had with disc brakes). Or you could step up to a 12-bolt / Ford 9" / Dana 60......
'JustDreamin'
Last edited:
big gear head
axle builder
Re: 28 Spline Axles
The 7.5 had 26 spline axles up to about '90, then it got the 28 spline axles.
The 7.5 had 26 spline axles up to about '90, then it got the 28 spline axles.