How do I find out if I have a 27 spline or a 30 on my 1999 TJ?

[Firstjeepbuild]

I have 99 TJ Sahara with a Dana 30 in front and 35 in the back. I want to make sure what my Dana 30 spline is before I order and ARB air locker for it. I believe it is has a 27 spline but I beed to verify. I might as well know what the 35 is as well. I called the dealer and they said I would have to pull the front diff cover and count.

 

[Jerry Bransford]

The factory installs 27 spline shafts in both the Dana 30 and Dana 35. For a front locker I'd replace the factory axle shafts with chromoly replacements like from Revolution Gear. A locker in the front has a nasty habit of breaking/stretching the front axle shaft's "ears" that hold the axle shaft u-joints.

What size tires are you running and are larger replacements in your future?

 

[Firstjeepbuild]

I forgot to say I run 32 in tires and use the jeep in sand, snow and mud hunting as well trail running no rock crawling.

 

[Firstjeepbuild]

I do not plan on going bigger than 32’s

 

[Jerry Bransford]

I forgot to say I run 32 in tires and use the jeep in sand, snow and mud hunting as well trail running no rock crawling.

Be careful to limit how much power you give the Jeep when you're in 4Lo and making a sharp/hard turn which is when the ears and u-joints are seeing the most stress. That's how I busted one of mine, I ended up limping out in 3wd while being towed over anything that could break the other side too. The inner axle shaft had to be removed before going any further.