Axle issues / annoyance

[ML]

What are the symptoms of an axle that needs to be refreshed? How am I on the original axles with probably close to 130k miles (original), never being touched and being a track only car for last 4 years? I have actually been watching a adapter for 350z axles being developed for our cars, and will hop on that asap.

[Opie]

Originally Posted by blsfrs

Opening an old thread. I've had 2 of my repacked axles fail in the same weekend. I filled the cv cup 1/2-2/3's full of Redline cv2 grease and packed it around the bearings. The first time the boot was torn and a few of the bearings fell out.I thought initially that I had a loose wheel. The second time the inner retainer pushed off, venting the grease. I saw the smoke and pulled in the paddock. Left side both times.. I'm na powered and lowered 1". The cups were still very hot 1/2 hour after coming into the paddock.
I'm trying to troubleshoot, Too much grease? Too little grease. After reading what you and others have written, I'm going to insulate my exhaust pipe.

Any other suggestions?

Sounds like way too much grease...should be just enough to coat the joint, like 6oz

[gt5759]

Originally Posted by ML

What are the symptoms of an axle that needs to be refreshed? How am I on the original axles with probably close to 130k miles (original), never being touched and being a track only car for last 4 years? I have actually been watching a adapter for 350z axles being developed for our cars, and will hop on that asap.

Please do elaborate on these said adapters I have not heard about.

[blsfrs]

Originally Posted by Opie

Sounds like way too much grease...should be just enough to coat the joint, like 6oz

I might be overthinking this but, is there a difference between 6 fluid ounces and 6 oz by weight?

I've already done it wrong twice.

[ML]

Originally Posted by gt5759

Please do elaborate on these said adapters I have not heard about.

This guys is pretty active on the 86 drift FB page, and is saying he is going to get some going to sell.

[gt5759]

Originally Posted by blsfrs

I might be overthinking this but, is there a difference between 6 fluid ounces and 6 oz by weight?

I've already done it wrong twice.

Just my 2 cents for what it's worth. Don't over think it. Pull them apart, clean all parts completely, scoop grease out with your hand from the tub and coat the sides of the cups, pack a little at the bottom of the cups, coat the balls, cages and the centers. Re-assemble and pack a little more grease on top of the assembled joint. Super simple, been doing this on my circuit race cars for 25 years. I just rebuilt 2 sets for mine for the brz this past weekend, same technique, using cv2 grease and red wd40 straws from amazon under the outer boot clamp's for venting.
If the balls fell out of the inner joint it was because it was assembled incorrectly, overextended to the point it bypassed the wire clip/retainer at the end of the cup or you broke/cracked the cage in the joint - done that too, usually only in high hp cars. Just my opinion's here, not poking fingers.
When disassembling the inners make sure to not damage the wire retainer at the front of the cup and make sure to not damage the c-clip on the end when you take it out and remove the center piece that's splined. When re-assembling, make sure all the balls stay in place in the cage when sliding into the cup, usually grease will hold them place. Then make sure everything rotates freely before sealing up the boots.
Little things to pay attention to - the ball cages are directional and the forged center piece that is splined and slides over the bar, those are directional as well.
The outers come apart like any Rzeppa joint does. I clamp the shaft in the vice, use flat faced bar or punch, hit the center closest to bar to pop it over the wire clip on the end, it's the same style clip that helps retain the cv axle in the differential. It takes a few good hard whacks with a 5lb sledge.

Other little side notes. Make sure the new cv boot clamps you install don't have anything sticking up that can chafe the boots and cause a tear after tightening them down - if the folds in the boot can touch a sharp edge or raised edge, fix it. I also have never had a cv fail from over being over packed, not really sure that's possible but might be wrong?

Hoping this my help a few people

[redlined600]

Originally Posted by ML

What are the symptoms of an axle that needs to be refreshed? How am I on the original axles with probably close to 130k miles (original), never being touched and being a track only car for last 4 years? I have actually been watching a adapter for 350z axles being developed for our cars, and will hop on that asap.

I only pulled mine apart after a boot exploded on track. Almost all of the components looked good except one race on the inner cup on the driver's side had some pitting. They made no noise, or the stereotypical "clicking". I switched that one to the pass. Side.

I'm convinced the exhaust completely cooks the driver's inner cv joint.

Protip, take pics when you pull it apart because the cages can go in backwards.

[blsfrs]

Originally Posted by gt5759

Just my 2 cents for what it's worth. Don't over think it. Pull them apart, clean all parts completely, scoop grease out with your hand from the tub and coat the sides of the cups, pack a little at the bottom of the cups, coat the balls, cages and the centers. Re-assemble and pack a little more grease on top of the assembled joint. Super simple, been doing this on my circuit race cars for 25 years. I just rebuilt 2 sets for mine for the brz this past weekend, same technique, using cv2 grease and red wd40 straws from amazon under the outer boot clamp's for venting.
If the balls fell out of the inner joint it was because it was assembled incorrectly, overextended to the point it bypassed the wire clip/retainer at the end of the cup or you broke/cracked the cage in the joint - done that too, usually only in high hp cars. Just my opinion's here, not poking fingers.
When disassembling the inners make sure to not damage the wire retainer at the front of the cup and make sure to not damage the c-clip on the end when you take it out and remove the center piece that's splined. When re-assembling, make sure all the balls stay in place in the cage when sliding into the cup, usually grease will hold them place. Then make sure everything rotates freely before sealing up the boots.
Little things to pay attention to - the ball cages are directional and the forged center piece that is splined and slides over the bar, those are directional as well.
The outers come apart like any Rzeppa joint does. I clamp the shaft in the vice, use flat faced bar or punch, hit the center closest to bar to pop it over the wire clip on the end, it's the same style clip that helps retain the cv axle in the differential. It takes a few good hard whacks with a 5lb sledge.

Other little side notes. Make sure the new cv boot clamps you install don't have anything sticking up that can chafe the boots and cause a tear after tightening them down - if the folds in the boot can touch a sharp edge or raised edge, fix it. I also have never had a cv fail from over being over packed, not really sure that's possible but might be wrong?

Hoping this my help a few people

Your advice is very helpful. Well worth 2 cents. I think that I had the basic assembly right. I drove the car around town for a week and then on the interstate for 2 hrs to get to the track without problems. The problem seems to be the heat generated by track driving. My right axle (the first one I packed) did fine. It was the left side that failed x2. After the 2nd failure, the axle held together and I was able to put a clamp on it and drive 2hrs home. I used the wd40 tube vent on the axles but I'm thinking too much grease didn't allow for air/grease expansion once things got really hot.



For the outer joints, I flushed them out with solvent and compressed air until the were clean. Just this week I saw a video describing dis/reassembly.


I've got oem new axles coming tomorrow. I'm going to clean and lightly repack my current axles and try them at VIR later this month. I'll carry 2 new spares and let y'all know what happens.

[Matt93SE]

*typically* when the boot explodes, it's because it wasn't vented properly and the heat causes the air inside to expand, then they swell and catch on something under the car.
Last time I looked at mine, the boot was real close to something on the subframe.

[blsfrs]

Originally Posted by Matt93SE

*typically* when the boot explodes, it's because it wasn't vented properly and the heat causes the air inside to expand, then they swell and catch on something under the car.
Last time I looked at mine, the boot was real close to something on the subframe.

Someone needs to do a video of that. I'm going to take the temperature of the cv cups after a session or 2 just to see how hot they get.

[Matt93SE]

Originally Posted by blsfrs

Someone needs to do a video of that. I'm going to take the temperature of the cv cups after a session or 2 just to see how hot they get.

A friend of mine that races an Integra got some video of his a while back after he kept having exploding boot problems. it's both cool and gross to watch.
The first time I rebuilt mine and installed the PBM differential risers, I could see marks on the bottom of the subframe where the boots had swelled and were rubbing on the subframe.

I redrilled the holes on the PBM mount to reduce the crazy driveshaft angle and lower the diff a bit away from the subframe, vented the boots with a WD40 straw, and the marks went away after that.

[blsfrs]

This weekend, I had a great time at NASA Mid-Allantic Oktoberfast at VIR. In the last session, I had a fun time playing cat and mouse with a 2nd gen. He was pretty much stock. I could haul him in through the turns but, needless to say, he pulled away on the straights.

I did temperature checks on my CV's. After the morning runs (45*-50* ambient) I got 195*-200* on the left CV and 165*-175* on the right. Morning temp on the bottom of the diff was 195*. I did 2 afternoon checks on Saturday, ambient 75*-80*. Early afternoon was 235* on the left and 224* on the right. After the last session on Saturday, Left 245* and right 225*.

My tailpipe is wrapped. I've seen the shields folks have made. Has anyone tried reflective tape on the CV cup?

[redlined600]

I'm actually surprised it's that close. I would have expected a higher delta between the two.

Here is what I'm planning on adding to shield the heat.
Design Engineering 010450 Titanium Pipe Shield 6" x 1' Exhaust Heat Shield https://a.co/d/9VmdMNG

[blsfrs]

Originally Posted by redlined600

I'm actually surprised it's that close. I would have expected a higher delta between the two.

Here is what I'm planning on adding to shield the heat.
Design Engineering 010450 Titanium Pipe Shield 6" x 1' Exhaust Heat Shield https://a.co/d/9VmdMNG

I had some header wrap from an earlier project. I'd curious to see if titanium is a better heat shield that what I used. Can we get the sides equal? Do we need to?