Is 33s on 27 spline 8.25 safe?

[NickLovesMarissa]

I've read everywhere that 33s can break Chrysler 8.25 27 spline axle shafts. Some say it happens some say it doesn't. What's your story? If 27 spline is a problem I can always get a 97 and up 29 spline Chrysler 8.25 at a junkyard in swap it in. But since it's gonna be a daily driver and a wheeler will the 27 spline be fine?

 

[markw]

The daily driver part won't break it, but wheeling a 27 spline stock shaft on 33's stands a pretty good chance of breaking it. You will also want to regear the axle as throwing 33's at these things kills your mileage and it kills your mileage even more if you don't regear.

 

[MrShaft696]

my opinion its a pretty decent axle, you would have to be pretty reckless on 33's to break it.....35's and a locker you can pretty much get in a situation to do anything.....

 

[NW-ZJ-SCOTT]

I've watched a 27 spline 8.25, Locked, 4.56s, with stock shafts, Hold up to 35s and heavy abuse for 3 years now..

Not saying its a Guaranteed reliable setup.. But what I've seen with my own eyes.. I'd run it!

 

[NickLovesMarissa]

What about a 29 spline?

 

[Hoooper]

"safe" is only how much you subject it to. 37s can be safe on a stock D30, or 35s can be "too big" for a D60, it completely depends on how you drive

 

[NickLovesMarissa]

Okay but what if I want to lock it? Also what gears should I use to take the stress off the shafts? Would I be better with 29 splines?

 

[Lowrange2]

It's fine. Run it until it breaks. Many, many, many people run 33's on a bone stock 27 spline 8.25. Just bolt them on there and go for it. Upgrade if you need to.

Also, did Marissa make you use that as your screen name?

 

[NickLovesMarissa]

Nah I like showing her off lol. Also couldn't think of a good user name.

 

[Maxxrus08]

I ran 33" on my D35 with 27 spline, 3.07, and open diff for a long time before upgraded. Did fine. Just less worry when you go to a 29 spline or bigger.

 

[sidriptide]

your 27 spline is a perfectly good starting place. but plan ahead for an upgrade. if you are going to spend the $$ on gears you might as well step up to the 29-slp now. your 33s will love 4.56s.
that being said i ran a 27-spl with a Detroit Locker in my first XJ on 33s for 2 years and then it spent another year getting beat on with 35s by a friend of mine. when he pulled the shafts to sell it he found twisted splines, but never actually broke.
dont throw too much $$ at it because a replacement is pretty affordable.

 

[NickLovesMarissa]

Well about the 8.25 29 spline. I was thinking of wheeling the 27 spline till it breaks a couple times and see if it's gonna be a normal thing but if it is a normal thing I thought about swapping in the 29 spline 8.25 or a ford 8.8. But is the 8.8 narrow enough to notice? Or would I be better off with build a 8.25 29 spline?

 

[Lowrange2]

If you're going to swap anything I'd swap in an 8.8.

 

[NickLovesMarissa]

Okay say I was too go with the 8.8. Wouldn't a 29 spline and 8.8 be equal? 8.8 is just one spline bigger plus the 29 spline is bolt on. I'm not a welder.

 

[blondejoncherokee]

if you cant weld stick with the 29 spline 8.25, but they are in no way equal.

8.25 Ring gear versus a 8.8" ring gear, and the 8.8 has a massive pinion gear, 31 spline shafts and they are beefy. The 8.8 is made to handle 6800 ft lbs, a dana 44 is around 4600-5000 ft lbs, and d35 is around 4200 . so an 8.25 would be in between the 35 and 44, say 4400 ft lbs of torque.


8.8 has discs, which is normally a 300$ swap on a 44, cheaper on a 8.25 , using junkyard parts.

 

[Lowrange2]

Okay say I was too go with the 8.8. Wouldn't a 29 spline and 8.8 be equal? 8.8 is just one spline bigger plus the 29 spline is bolt on. I'm not a welder.

if you cant weld stick with the 29 spline 8.25, but they are in no way equal.

8.25 Ring gear versus a 8.8" ring gear, and the 8.8 has a massive pinion gear, 31 spline shafts and they are beefy. The 8.8 is made to handle 6800 ft lbs, a dana 44 is around 4600-5000 ft lbs, and d35 is around 4200 . so an 8.25 would be in between the 35 and 44, say 4400 ft lbs of torque.


8.8 has discs, which is normally a 300$ swap on a 44, cheaper on a 8.25 , using junkyard parts.

All ya have to weld on is the spring perches. $25 at a welding shop and you have an 8.8 ready to swap in.

 

[NickLovesMarissa]

I think I'll wheel the 27 splines and if it doesn't give me trouble I'll stick with them but if it does I'll get a 29 spline axle and swap in. 29 splines good with 33s right for weekend wheeling and daily driving? Also does lift have anything to do with axle shaft breakage I'm getting a 6.5" lift.

 

[kastein]

I ran a 27 spline 8.25 open on 33" BFG AT knockoffs for a year, wheeled it everywhere and beat the snot out of it, never had an issue. But I carried spare shafts in the back.

I would recommend carrying spares, but wouldn't worry about it too much. Adding more aggressive tread or a locker should mean you are less abusive on the throttle.

Lift isn't going to change axleshaft breakage at all, why would it? However, tire and wheel weight will, and terrain will. If you are going to lock it, pick up a set of 29 spline shafts and a 29 spline full case locker or a 29 spline lunchbox locker plus a 29 spline open carrier, it all goes right in. You'll need to reset your carrier bearing preload and ring gear backlash in the process because the 8.25 is a side adjuster based axle not a shim adjusted axle, but that's pretty easy.

 

[techno1154]

I do not understand this but,.....if you are going to swap in another differential why beat around trying to decide between the D44, 8.8 or a 27 spline 8.25. Go the easiest route first time and do not look back. If you have a D44 from an XJ go that route. Change the gears, repair or replace the brakes bolt it in and wheel it. I hear the 8.8 is a good swap because of the extras you get up front, extras like 4.10 gears, LSD and disk breaks but,....you have to weld on perches and maybe weld the tubes to the pumpkin and wheel spacers depending on the wheel back space you are using. If an 8.25 is your choice go directly for the 29 spline. Done.

My XJ have a D44 but that was only because I had it laying around for a few years. It needed to be repaired. So did the 8.25 under the XJ at the time. The D44 won over the 8.25 only because it was only a 27 spline.

 

[kastein]

I think he was asking because he currently has a 27 spline 8.25 in the jeep factory, but I could be wrong, he didn't say either way.