Getting ready to regear to 4.88s and get a detroit locker in rear. Is it worth it to ditch my 27 spline rear axles in my 8.25 and move to 29's while I am at it?

 

If you're getting a full case locker, get the 29 spline and grab a pair from the junk yard. Might as well go big spline wise so you're not regretting getting a 27 spline locker wishing you had gone up to 29 spline

 

So the 29s are that much better?

 

Yea. Unless you want to run basically a larger Dana 35 with a locker and money thrown at it to break on bigger tires.

 

Hmmm, no I probably don't want to go that route!

 

Yes do that swap for sure I run the 29 splines with my Detroit Locker and 35" tires. A pair of stock axles are cheap from the JY and I also carry spares as if something breaks I want it to be them and not locker or gears.

 

2 splines aren't gonna make that axle break like a Dana 35. You still have a way larger ring and pinion in the 8.25. If you're swapping to full case locker then it can't hurt.

 

Absolutely swap over now. Don't even consider buying a 27 spline Detroit. No reason to buy a weaker part over the price of a couple stock shafts.

 

The stock 29 spline shafts are about 25% stronger than stock 27 spline shafts. I got 29 spline 1541H shafts for $205.

 

i concur ,you should do that swap. that way in the future go to 29 spline alloy shafts then you really getting close to bullet proof.

 

I would like to see evidence of this. Any testing done?

 

Axles 101 article: By Jim Alien page 60. I never just make stuff up, I twisted a tube and took out driveshaft u joint, but my 1541H shafts were fine.

 

I wasn't asking about 1541 shafts. I'm talking about the 25% decrease in strength between a stock 29 spline shaft and a stock 27 spline shaft. That's a drastic decrease. Its kinda hard to believe for .04" difference in diameter between shafts.

 

The magazine article stated 25% difference between stock 27 & 29 spline shafts for the C8.25

I was giving the op an example of my experience with the1541H shafts.
Which have an approximate 55% higher yield strength than standard
1040 carbon steel.

 

Material wise the 1541h is only 25% stronger than 1040/1050 shafts. Most companies state that right on their websites. I'm not believing the 25% between stock shafts.