Pre-97 vs. Post-97 8.25 axle?

I wanted to throw this out for some opinions - topic that's been beat to death but a new twist. (also cross posted on jeepforum).

Here's the specs from jeepforum on the 8.25 axle:

Chrysler 8.25 - 27 spline, 1.17" diameter shafts, 8.25" ring gear, 3" axle tube - used 91-96
Chrysler 8.25 - 29 spline, 1.21" diameter shafts, 8.25" ring gear, 3" axle tube - used 97-01

And this post is a nice writeup of relative strengths: http://www.naxja.org/forum/showthread.php?t=983204

Here's one piece of info that was in it:

AXLE STRENGTHS:
COT - Continuous Output Torque
MOT - Maximum Output Torque

Dana 35 ........................ COT: 870 MOT: 3480
AMC 20 .........................
Chrysler 8.25 .................
Dana 53 ........................
Dana 44 ........................ COT: 1100 MOT: 4460
Ford 8.8 28 spline ........... COT: 1250 MOT: 4600
Ford 8.8 31 spline ........... COT: 1360 MOT: 5100
Dana 60 semifloat ........... COT: 1500 MOT: 5500
Dana 70 ........................
Rockwell 2.5 Ton ............

I'm considering swapping out my Dana 35 for an 8.25 (I have a bead on a D44 out of an MJ though) I have a 99XJ/Auto/AW4 D35 rear.

What I'm wondering. A 91-96 XJ C8.25 shaft is not much larger than the D35 (though the ring gear and tubes are) I think everyone agrees that an 8.25 is better, but I assume it should be the 97+ 8.25 axle with 1.21" diameter shaft. How significant is the axle tube diameter in this discussion?

Am I splitting hair here? Is the pre-97 8.25 still signficantly stronger than the D35? Is the 97+ 8.25 that much better than the 91-96 8.25 or negligible?

For keeping w/ stock specs for a 97+, I could see the benefits of waiting for a later model 8.25, there's one I can buy now out of a 91-96 pretty cheap though.

Any thoughts or input appreciated.

Any 8.25 is a good upgrade from a D35. The 29 spline 8.25 is slightly stronger than the 27 spline. You can put 29 spline parts in a 27 spline if you replace the carrier, this would be useful if you find a good deal on a 27 spline and want to put a 29 spline locker or something in it. You just replace the shafts and the carrier. The 29 spline 8.25 is equivalent to a D44 IMHO. There are junkyard disk brake upgrades you can do to any 8.25. If money's tight you can install two of the long brake shoes on each side for an improvement in braking.

The common big benefit of getting rid of a D35 is getting rid of the C clips, they have been known to break and thus will allow the wheel and shaft assembly to walk right out of the housing. A pre 97 8.25 that is 27 spline would be better than a 35 and a 97+ is better yet, and for bolt in ability a 44 out of a late 80's xj is still even better. If you could get the 44 out of the MJ all you would have to do is swap the leaf perches as I believe they were all spring under.

dave92cherokee said:

The common big benefit of getting rid of a D35 is getting rid of the C clips, they have been known to break and thus will allow the wheel and shaft assembly to walk right out of the housing. A pre 97 8.25 that is 27 spline would be better than a 35 and a 97+ is better yet, and for bolt in ability a 44 out of a late 80's xj is still even better. If you could get the 44 out of the MJ all you would have to do is swap the leaf perches as I believe they were all spring under.

Click to expand...

Show me an instance where a c-clip failed while on a trail.

Not saying it doesn't happen (though highly unlikely), but too many people jump on the "I hate c-clips" bandwagon with no reasoning.

MoparManiac said:

Show me an instance where a c-clip failed while on a trail.

Not saying it doesn't happen (though highly unlikely), but too many people jump on the "I hate c-clips" bandwagon with no reasoning.

Click to expand...

X2. Know your limits and you won't ever run into a situation where c-clips would be an inconvenience.

MoparManiac said:

Show me an instance where a c-clip failed while on a trail.

Not saying it doesn't happen (though highly unlikely), but too many people jump on the "I hate c-clips" bandwagon with no reasoning.

Click to expand...

Its Not the C-clip failure thats the problem.Its Axle shaft failure and the fact that there is nothing to hold the shaft and wheel on/in the housing.
Thats why the D44 is a better way to go if possible.Pressed on bearing will keep the wheel assembly on the vehicle,repair is still needed if axle is broken.

Wayne

Wayne Sihler said:

Its Not the C-clip failure thats the problem.Its Axle shaft failure and the fact that there is nothing to hold the shaft and wheel on/in the housing.
Thats why the D44 is a better way to go if possible.Pressed on bearing will keep the wheel assembly on the vehicle,repair is still needed if axle is broken.

Wayne

Click to expand...

:banghead:

I know.

What I was speaking to was the fact that dave92cherokee stated the c-clip itself being a weak link. I have never seen a c-clip break. Sure the shafts break and walk out, but show me an instance where a c-clip broke.

Again, not saying it doesn't happen, but with that mindset people wouldn't be swapping in 8.8s.

im i the only one to think that you would stop when you broke a shaft and not drive on one? and if you think your wheelin hard enought to break a shaft that you would bring spares? on the topic of axles i blue up a d35 on the street with stock tires, ran a 27 spline 8.25 in my current jeep with 33's for 5 months and beat the living crap out of it it was till in perfect shape when i pulled it i swapped in a 29 spline with aussie locker and have been beating the crap out of that one since may with no issues

"im i the only one to think that you would stop when you broke a shaft and not drive on one? and if you think your wheelin hard enought to break a shaft that you would bring spares? on the topic of axles i blue up a d35 on the street with stock tires, ran a 27 spline 8.25 in my current jeep with 33's for 5 months and beat the living crap out of it it was till in perfect shape when i pulled it i swapped in a 29 spline with aussie locker and have been beating the crap out of that one since may with no issues "

X2. I broke a 35 shaft going 15 mph on a graded dirt road with 31's. My 91 with stock 27-spline 8.25 has never had a problem and my 90 with a swapped in 29-spline 8.25
hasn't either. Both are good.

Good feedback - thanks all. So how about aftermarket, gears, lockers, etc. Is there good availabilty for either the 27 or 29 spline, or would I typically upgrade the components to 29-spline before getting lockers, etc.

Oh - and if I don't know what year the donor XJ was, can I tell from the tag on the diff cover if it was pre/post 97?

grizbait said:

Good feedback - thanks all. So how about aftermarket, gears, lockers, etc. Is there good availabilty for either the 27 or 29 spline, or would I typically upgrade the components to 29-spline before getting lockers, etc.

Oh - and if I don't know what year the donor XJ was, can I tell from the tag on the diff cover if it was pre/post 97?

Click to expand...

ya gotta pull a shaft and count the splines

um dont 8.25,s also have "C" clips

Ewenm said:

um dont 8.25,s also have "C" clips

Click to expand...

Yupp, i've got a 27 spline and im running 35's on it no problem. I'll prolly be getting a 29 spline aussie and upgrade the shafts with jy ones when i put the locker in. I think that strength wise the 29 spline is very close to a 44. If not a match. The only big draw back is aftermarket support for the 8.25, it's not much when compaired to the 44.

ROBZ95Xj said:

im i the only one to think that you would stop when you broke a shaft and not drive on one? and if you think your wheelin hard enought to break a shaft that you would bring spares? on the topic of axles i blue up a d35 on the street with stock tires, ran a 27 spline 8.25 in my current jeep with 33's for 5 months and beat the living crap out of it it was till in perfect shape when i pulled it i swapped in a 29 spline with aussie locker and have been beating the crap out of that one since may with no issues

Click to expand...

I've seen how hard Rob beats on his shafts, if he can't break an 8.25 I'll use one any day of the week. I have one right now (but don't wheel on it anymore due to a gimpy front axle atm) and will only be swapping in an 8.8 because disc brakes + 4.10s + stronger axle for $200 total vs staying with drums + same axle and switching to 4.10s for $250-300+ was a no brainer for me.

dave92cherokee said:

The common big benefit of getting rid of a D35 is getting rid of the C clips, they have been known to break and thus will allow the wheel and shaft assembly to walk right out of the housing. A pre 97 8.25 that is 27 spline would be better than a 35 and a 97+ is better yet, and for bolt in ability a 44 out of a late 80's xj is still even better. If you could get the 44 out of the MJ all you would have to do is swap the leaf perches as I believe they were all spring under.

Click to expand...

not all d35 are c-clip. d35c from 84-89 or 90 are non c-clip.

with that said, swapping out the d35 is all about axle strength, not because of the c-clip

kastein said:

I've seen how hard Rob beats on his shafts

Click to expand...

:roflmao:

lastara

Oh man thats just wrong haha!

nochance9 said:

Yupp, i've got a 27 spline and im running 35's on it no problem. I'll prolly be getting a 29 spline aussie and upgrade the shafts with jy ones when i put the locker in. I think that strength wise the 29 spline is very close to a 44. If not a match. The only big draw back is aftermarket support for the 8.25, it's not much when compaired to the 44.

Click to expand...

You'll still need to replace the carrier as the opening for the axle shaft is bigger on the 29 spline. The 29 spline shafts won't through the hole in the 27 spline carrier. At least that's what I've read.

MoparManiac said:

:roflmao:

lastara

Click to expand...

hahahaha :roflmao:

Ewenm said:

um dont 8.25,s also have "C" clips

Click to expand...

Yup, they're "C" clipped also.




Fred