8.25 internally swap

Dragonlich1961 · Apr 12, 2016

A thought popped into my head while preparing a jy run.
If I was to purchase a kj8.25 with disc. Could I use that to upgrade a 27 spline Xj 8.25 to 29 spline. I'm talking swaping axles and carrier. Last I checked I though the kj was a 29 spline. Most people steal the brakes off of these anyways. Why not buy the axle and swap guts to get the brakes while disc upgrading a 27 spline. Two birds with one stone. Proprably just as cheap as buying the nessesay parts to make the brake swap.

Just a thought.

need-a-bow · Apr 13, 2016

That actually sounds like a great idea

Sent from my SM-G900V using Tapatalk

Serious Offroad · Apr 13, 2016

Why not cut the brackets off the new axle and weld on some perches and shock mounts. Much faster and you don't need to have the gears set up.

I know a guy that sells the parts you'll need...

IslanderOffRoad · Apr 13, 2016

Is the kj axle the same width?

Demonoid369 · Apr 13, 2016

Serious Offroad said:
Why not cut the brackets off the new axle and weld on some perches and shock mounts. Much faster and you don't need to have the gears set up.

I know a guy that sells the parts you'll need...

^x1,000
Unlike the d30 where you can remove the carrier and place it back in without regearing, the 8.25 you will have too. At least if you cut the brackets off and weld on new perches on the kj 8.25, you can set the pinion angle for your rig

Sent from my iPod touch using Tapatalk

Demonoid369 · Apr 13, 2016

IslanderOffRoad said:
Is the kj axle the same width?

I believe so, I remember seeing a thread on here referring the axle shaft and they measured the same. Could be wrong though

Sent from my iPod touch using Tapatalk

Dragonlich1961 · Apr 13, 2016

Hoping to go for a no weld swap since the kj use a 4 link coil setup with a weird mount on the pumpkin. Hell if you were buying a new carrier and needed some shafts, if they were the right lenght thenjust get the shafts and backing plates and use your new carrier of choice. Saves buying shafts and gives people more options. Some kjs even came with factory LS some that might be an option.

Just food for thought.

Serious Offroad · Apr 13, 2016

Still faster and less costly to cut off the existing brackets and weld on some perches and shock mounts.

But...
It's your rig and your money so best of luck with your project.

md21722 · Apr 13, 2016

Swapping carriers requires full set up of the gears to set pinion depth & back lash. If you have a welder or access to one, Frank (Serious) is steering you the best way.

D.I.T.A · Apr 13, 2016

I thought you could just swap in the 29 spline side gears in to the 27 spline carrier ?

Wooooooo my 1,000th post !

md21722 · Apr 13, 2016

D.I.T.A said:
I thought you could just swap in the 29 spline side gears in to the 27 spline carrier ?

Wooooooo my 1,000th post !

Nope, they won't fit. Need to swap the carrier.

Dragonlich1961 · Apr 13, 2016

I'm understanding the gear and carrier Problem. But kj 8.25 most offten come with a 3.73 gear. Not compatible to most stock xj's. So one way or another you need to have one set of gears installed.

Could one not use the shafts and brakes to upgrade their 27s to 29s with discs, provided they get a carrier to go as well. Gears still need installed yes since you got a new carrier. It's a popular axle for brakes and more kjs are beginning to hit the yards then our slowly dieing breed of xj's. It's hard for me to find 96- xj's in yards. Lots of 2000-01 (stupid 0331)

Plus if you only had the Xj it's easier to bring home two axle shafts and two backing plates then a whole axle. If doing the swap you would have to order the new brackets and a set of gears for at least one diff due to mismatched gears.

themauler · Apr 13, 2016

Dragonlich1961 said:
I'm understanding the gear and carrier Problem. But kj 8.25 most offten come with a 3.73 gear. Not compatible to most stock xj's. So one way or another you need to have one set of gears installed.

Could one not use the shafts and brakes to upgrade their 27s to 29s with discs, provided they get a carrier to go as well. Gears still need installed yes since you got a new carrier. It's a popular axle for brakes and more kjs are beginning to hit the yards then our slowly dieing breed of xj's. It's hard for me to find 96- xj's in yards. Lots of 2000-01 (stupid 0331)

Plus if you only had the Xj it's easier to bring home two axle shafts and two backing plates then a whole axle. If doing the swap you would have to order the new brackets and a set of gears for at least one diff due to mismatched gears.

Get a 29 spline 8.25 from the JY and then grab the backing plates and brakes off of the Liberty for a total upgrade. To put 29 spline axles into the a 27 spline 8.25 axle requires a gear set up since you would need to instal the carrier and spider gears.

If you are worried about strength, a 27 spline 8.25 will live up to 35s. Not invincible but very manageable. Just put KJ brakes on the 8.25 you have now and carry a spare axle shaft.

Digger87xj · Apr 13, 2016

no need to set pinion if all you are swapping is ring gear from one carrier to the other, backlash is all that is needed to readjust.

dan1977p · Apr 13, 2016

Digger87xj said:
no need to set pinion if all you are swapping is ring gear from one carrier to the other, backlash is all that is needed to readjust.

Except that pinion and ring gear are matched sets and need to be moved together.

Digger87xj · Apr 13, 2016

dan1977p said:
Except that pinion and ring gear are matched sets and need to be moved together.

right but all he is changing is the carrier.

Digger87xj · Apr 13, 2016

md21722 said:
Swapping carriers requires full set up of the gears to set pinion depth & back lash. If you have a welder or access to one, Frank (Serious) is steering you the best way.

Nope... just backlash.

dan1977p · Apr 13, 2016

Digger87xj said:
right but all he is changing is the carrier.

I missed that. It looked to me like he was wanting a gear change in there too. If it's just to upgrade to a 29 spline carrier, I'd say it's just not worth it. I was trying to do the same and it ended up being too much hassle for no real gain on 33's.

Digger87xj · Apr 13, 2016

dan1977p said:
I missed that. It looked to me like he was wanting a gear change in there too. If it's just to upgrade to a 29 spline carrier, I'd say it's just not worth it. I was trying to do the same and it ended up being too much hassle for no real gain on 33's.

he wants the disk brake setup from the KJ as well.

dan1977p · Apr 13, 2016

Digger87xj said:
he wants the disk brake setup from the KJ as well.

Now I'm understanding why Serious is recommending cutting off the perches and putting new XJ ones on. Never heard of anyone taking a complete KJ axle and running it under an XJ.

I want to recap since I know I'm not the only one confused.

Option 1:
Buy complete KJ axle (assuming it actually is
Pull carrier, change ring gear to be the current xj and put KJ carrier in XJ 8.25
Pull shafts from KJ and use in XJ
Pull disc brakes from KJ and use on XJ

Option 2:
Buy complete KJ axle
Remove existing suspension mounting and burn new XJ compatible mounts
While there you can rotate if you have a SYE and get rid of shims
If gearing doesn't match XJ front, take used XJ ring and pinion and set them in the KJ axle

Option 3:
Abandon the 29 spline quest (the benefit seems to be very subjective)
Pull disc brake parts from KJ axle and only pay for them. Just did mine for $40 which is far less than the $175 it would have cost to buy the complete axle
Put parts on XJ

I like 3 but I just did that so it's fresh in my mind. If I want a stronger axle I'll build an 8.8, 44 or maybe even a 9in following the #2 option.

8.25 internally swap

NAXJA Forum User

NAXJA Member

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

NAXJA Forum User

Similar threads