so i asked this question before it never eally got answered, just started an argument....i have both a 26 and 28 spline rear end.....i am just curious to know, HOW much stronger is the 28 vrs 26, and Were there any other differences....material of axels ect ect.....


i dont need to know exactly at what lbs the axels break or anything...a simple "barely stronger" or "alot stronger" will do

 

well the 28 splines would be needed if ur going to use like a slp post for instance so i assume that the 28's would be better since thirdgen were upgraded with some latter on.

thats all i know or could say.

 

yeah i mean i know the 28 is better, and slp posi will only fit 28 spline....also 28 spline was used til the end of f-body production.

i know its a better rear end....i was just asking cause i have a 26 sitting in my garage and a 28 on the car, would be easier to take my time and build the 26 into the 3.73 posi carrying bastard....but if the 28 is THAT much better, well 28 it is....

 

Based on the increased spline count the 28 spline axels are about 10% stronger. The 28 spline axels will not fit into a 26 spline carrier without machining. Most of the aftermarket differentials are designed with 28 spline side gears. I would run the 28 spline rear. I upgraded my 26 spline rear with 28 spline axels and a host of other goodies.

 

I doubt 26 or 28 spline strength matters much. The 7.5" gears would prolly break before an axle does. However there is a slight strenth increase, so if you want the absolute strongest 10 bolt, then go with the 28s. I would go with the 28 just because it is the newer style, and any 4th gen posi will fit it. Also Superior makes 3rd gen axles in 28 spline in case you wanted to upgrade to stronger axles. I think parts will be easier to get for a 28 slpine rear.

 

ok that answers it...lol ty....i was just asking because it would be easier to use the 26 spline becausr i have the 26 spline rear jsust sitting htere,and can take all the timei wantputting the gears in.....ebay has 26 spline 3 series posi units for around 50 bucks...was going to get one ....got the slp one on the way.....might just sell the slp one and get a 26 spline posi....makes life alot easier with the whole rear in the garage for however long i need it to be....

 

Go ahead and build the rear for 28 splines. The housings are the same. Then when you go to swap just swap axles and put the cover on. Axles are easy to swap and it would take no time at all.

 

The axels aren't that easy to swap. 28 spline axels won't work in a '26 spline carrier. Not just because the side gears are different either. A 28 spline axel is too wide to go through the holes in the end of the 26 spline open or posi case.

I ran into this problem myself. My solution was to simply ream out the case, but this has to be done with the case out of the car. I used a boring bar, followed by several grits of brake hone stones to ensure that the bore was polished and free of stress risers.

If you plan to do the axel upgrade in the future you are going to be bucks ahead to just hold off on the posi until you are ready to run the 28 spline axels.

 

I'm talkin about building a 28 spline rear end out of his old 26 spline rear housing, not the 26spline carrier. Dont use the carrier just use the rear end housing. Then put his 28 spline axles in the new rear just before swapping it in. I know the axles wont fit in the 26 spline carrier but he's buying a new carrier now anyway. This way he can have the gears and everything setup in the spare rear while he still drives his car around.

Think we're just getting carrier and housing all messed up here. Message seemed clear when I put it down, but guess its hard to read my mind eh??


Edit: carrier=part ring gear bolts to; housing=part that everything bolts into and supports the car