Changing CV joints (front right and left axle assemblies)

[tom4bren]

Okay... apparently, no one has actually changed out an entire axle assembly, or at least hasn't come forward. As Tom4Bren said, it's much more involved than the simple 4-bolt, 1-retaining ring instructions for changing just the boots.

I have ... twice.

Here's what I've found after taking it apart as far as I dared.

A complete axle assembly is built like this:

outer spline->outer CV joint->shaft->inner CV joint->cup (also called an inner housing)->inner spline

The CV boot repair instructions are helpful, but they leave the splines attached to the vehicle. This is because you can simply pull the inner CV joint out of the cup, easily disassemble it, and slide the new baffles on from that end.

If you want to remove and replace an entire assembly, including the splines, a much more involved process is required:

OUTER SPLINE: From what I can see, complete disasembly of the wheel is required. This probably will involve removing the brakes, removing that big honkin axle nut, repacking the bearings, etc. Unfortunately, I can't find anything here detailing this. Even the manual seems to be a little sparse.

No, you can disassemble the inner CV per the boot instructions - then remove the hub cover (6 allen bolts) - then remove 1 clip ring on the spline - then just slide the inner CV with shaft out of the hub assembly from the inside.

INNER SPLINE: You have to completely drop the differential to remove the inner splines and cups. There is an excellent tutorial on this.

Yes

Caveat: Depending on how much slack is present, you do not HAVE to replace the inner cup. You can simply purchase an axle assembly which stops at the inner CV (doesn't have the cup/inner housing), and reuse the prexisting cup. However, I've heard that the bearings in the aftermarket CV axle assemblies are smaller than factory, and will rattle around in the cup.

I have no response to that

I would expect however, that if only your outer CV joint is bad, and you've purchased an axle assembly without the inner housing, you could disassemble the new inner CV on on the replacement axle assembly and use the CV joint from the old one instead, couldn't you?

Yes, as long as the short shaft between the CVs has the same spline geometry at the inner CV.

I anyone has more information on removing the wheel assembly to get at the outer CV spline, I'd appreciate it.

Look in the Download Section for Kenny's bearing re-pack instructions. PM me if you can't find it & I'll send you the pdf.

Thanks

-Mike

[mcaramb]

Awesome that I don't have to completely take apart the wheel... will look at it today.

Would you recommend changing the cups?

What's the best way to test if they are hosed?

The boots were sealed and were in perfect condition, no grit in the grease, there was a little play in them, but real little, and it might have just been total slack down the drive train to the diff.

Would it be worth the effort of dropping the diff?

I got my axle assemblies from O'Reilly (includes the cup). While playing around with it, it surprised the hell outta me that I was able to pull the inner CV right out of the cup by hand (boot still attached). I immediately pushed it back in and felt around for missing balls and didn't find any, so it looks like it went back together ok, but I don't know why they didn't put a retaining ring in their cup to stop that from happenning.

Anyone have any experience with the O'Reilly assembly?

UPDATE - I pulled the boot off the O'Reilly assemby to see if the shaft geometry matched my old inner CV (intending to keep the old bearings since I'm no longer changing the cup), and discovered why it slid out on me earlier. It's not an Rzeppa joint at all, it's a Tripod joint, thus completely a different architecture. The cup is a bit larger than the stock cup, so that should have given me a clue. I put it back together neatly and returned them to O'Reilly. I've ordered the assemblies from Autozone instead (without the cup). I'll let you know how well it matches up to the original stock inner CV geometry when they come in.

-Mike

[tom4bren]

BTW, here are some instructions for the clip ring you'll need to pull for the outer shaft removal:

http://www.4x4wire.com/isuzu/tech/manualhubs/

You can run your finger along the grooves on the inside of the green cup. Rough with divets & grooves = worn; smooth = good.

If the only play was associated with the outer CVs, then yes, you can probably re-use the inner CV components.

[mcaramb]

OMG that was easy.

No need to drop the differential, I'm not going to replace the inner splines.

7 allen bolts and one lock ring later, I'm holding an axle in my hands Now that I've figured it all out, I literally had the other one off in under an hour (including jack up, and tire removal time)

I felt inside the cups as you suggested and they are perfectly smooth as were the ballbearings, chase and pivot bearing parts. Break cleaner is your friend. The grease just melts off.

I'm still waiting for the autozone parts to come in (sometime today they swear), but should have it all back together in a few hours if things match up. Will let everyone know.

I may take pics and put together a complete CV axle replacement guide so folks don't have to piecemeal the instructions from one place or the other like I did. Will post soon.

-Mike

[mcaramb]

Just curious, in a pinch, could I drive it like this with no axles attached?

Or, does there have to be some steel inside the core of the wheel bearings? Without the spline there, it seems like those bearings would be pretty structurally weak.

-Mike

[tom4bren]

Sorry, I can't answer that one for you. I had disassembled outers to run in mine while the CVs were being re-built.

[mcaramb]

UPDATE: The AUTOZONE replacement CV axles (WITHOUT the CUP) are indeed much smaller than the original stock. According to my caliper, the complete INNER BEARING assembly is more than 1/8" smaller in diameter from outer edge of one bearing to the outer edge of the bearing 180 degrees across from it. That's after compressing the both assemblys in the comparison inward as much as possible so slack wouldn't skew the result.

That's pretty significant. I don't think I want to put that in the stock cup. My guess is that it would eat itself within a year. If anyone has experience using smaller aftermarket bearings in the cup, I'd like to know how long it's lasted you.

Now, to my idea of simply replacing the bearing on the end of the shaft. Well, that's out. The rebuilt Autozone shaft has a 25 (approx) tooth spline on the inner bearing end. The stock shaft has a 33 (approx) tooth spline. So you can't interchange them. Why they are different, considering these are rebuilds is beyond me. My best guess is that they are rebuilds from a Trooper or something.

So... does anyone besides Autozone sell just the CV Axle without the cup? ie: with a Rzepper joint, not a Tripod?

thanks
Mike