jbc3 Posted June 17, 2007 Share Posted June 17, 2007 This afternoon I was out on a cruise and stopped by a friends house. Of course he egged me on to stripe the road in front of his house. All I heard was BOOM! The MM billet stub axle broke clean on the passenger side. I'm going back tomorrow with the trailer to get the car and I'll post a few pics. I was running street tires too. Fortunately I was some place where I had help and I could leave the car, and not out in the middle of nowhere. (got to look for something positive) Jody Pictures added looking at the bearing race, broken axle inside Looking at the companion flange, still bolted to the CV. Broken end of axle inside. Close up of above pic cleaned up straight on of above pic. End of broken axle in the companion flange. Broken end of stub axle, after knocking it out of the companion flange. Bolt and washer still attached. Stub axle. Close up of break. Shered off and twisted the splines. Looking at the splines of the companion flange, where the break occurred. No significant damage. I set the broken piece back on the axle. Quote Link to comment Share on other sites More sharing options...
lbhsbZ Posted June 17, 2007 Share Posted June 17, 2007 Thats disturbing....especially after I coughed up the cash for a set of Ross's indestructable stubs. Try to post pictures before and after disassmebly so we can try to piece together what went wrong. A burnout doesn't put much stress at all on a stub axle I wouldn't think....not compared to cornering loads and having the tires stick. Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted June 17, 2007 Share Posted June 17, 2007 Thats disturbing....especially after I coughed up the cash for a set of Ross's indestructable stubs. Try to post pictures before and after disassmebly so we can try to piece together what went wrong. A burnout doesn't put much stress at all on a stub axle I wouldn't think....not compared to cornering loads and having the tires stick. A burnout can be quite rough on an axle if the wheel hops or it goes from spinning to hooking up quickly. Cornering puts side loads on the axle and not torsional loads. Need to see pics of how it failed and where, hopefully the wheel remained captured! Quote Link to comment Share on other sites More sharing options...
jbc3 Posted June 17, 2007 Author Share Posted June 17, 2007 The car never even moved an inch... 3 grand and as I let the clutch out (not side stepped) Boom it went. I actually first thought it popped out of gear. Now, the car has been to the track a hand full of times on slicks with a bunch of 10 second passes and several 1.47 60' times and I have indeed smoked the tires a time or twenty , but as a general rule, driving the car to work or around town, it's just cruising. The set-up on this car has been great, it never wheel hops at all and the tires I run are huge (285/50/16). They suprisingly hook extremely well on the street. Unless I really try to spin the tires, it dead hooks... even on the spray! I am not trying to say that I am gentle on the car, but I bought these thinking they were not going to be a problem... I took a quick look under the car and pulled the axle down after pulling it up my friend's 800' driveway. The CV joint and companion flange appear to be fine. The stub axle looks like it broke flush with the end of the companion flange. Unless someone has a better option... I will likely be buying another set billet stubs. Up to now they have been great... and it would cost ALOT more to change direction and go with a different set-up. Jody Quote Link to comment Share on other sites More sharing options...
Mikelly Posted June 17, 2007 Share Posted June 17, 2007 Jody, I have a set in my car, and this is a bit disturbing. However, I keep telling myself those 10 second passes probably are a lot more harsh than I'll be on them on a road course... God I hope so anyway! Mike Quote Link to comment Share on other sites More sharing options...
Mikelly Posted June 17, 2007 Share Posted June 17, 2007 A burnout can be quite rough on an axle if the wheel hops or it goes from spinning to hooking up quickly. Cornering puts side loads on the axle and not torsional loads. Need to see pics of how it failed and where, hopefully the wheel remained captured! Woa, we have a stranger in our house! Jim, good to see you on the site again, after such a long absence! Mike Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted June 17, 2007 Share Posted June 17, 2007 Sounds like they have taken some pretty good stress in the past - 1.47 60s is pretty good to say the least! I'd bet that the axle was damaged and a time bomb waiting to go off It might be a good idea to pull both of them and see what condition the other is in, if they have an index stripe on them you can see if they have twisted at all. I'd bet that OEM axle stubs wouldn't have lasted so well! There's an 8second 2JZ powered 240Z using these stubs I think who should probably be pretty worried! I cannot imagine having one of these fail at speed, particularly under really hard accel at the track Yeah Mike I'm around a bit. I may yet wake my car up to have something to work on until the Supra is finally settled and I may yet drop a 2JZ into the 240 I think the 2JZ would be much more fun than the 383 Meanwhile I'm reading up on developments since I was last around. These axles sound like a pretty good replacement and hopefully a failure analysis will be done and improvements made.... Quote Link to comment Share on other sites More sharing options...
v80z Posted June 17, 2007 Share Posted June 17, 2007 Do you think the upgrade to 295/50/16s contributed to the failure? Quote Link to comment Share on other sites More sharing options...
TimZ Posted June 17, 2007 Share Posted June 17, 2007 Did you actually see the stub broken off? There is a known issue with the CVs popping out if the travel limiters aren't installed, and the symptoms would appear the same - well, except for the potential wheel falling off thing... Glad nobody got hurt. Quote Link to comment Share on other sites More sharing options...
Sven Posted June 17, 2007 Share Posted June 17, 2007 I hope you already contacted Ross and gave him a chance to investigate the failure before airing this on a public forum. Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted June 17, 2007 Share Posted June 17, 2007 This is the first instance of someone breaking one of Ross' stubs (atleast to my knowledge). Keep us posted on the developments. BTW, I am still on the stock 280z stubs, but have considered going to the MM units. I am anxious to find out the results. Could you post some photos of the carnage when you get it disassembled? Thanks in advance, Mike Quote Link to comment Share on other sites More sharing options...
jbc3 Posted June 17, 2007 Author Share Posted June 17, 2007 I am not trying to trash Ross or the stub axles... I think that I am the first to break one of these... I was also one of the first to buy them. Yes I did see that the axle was broken, not the CV joint. I am uploading the pictures and will edit them into my first post. As far as the 296/50/16's, I believe that they did significantly contribute to the failure. They hook like slicks on the street. When you consider that before my head cam swap, I was making 589 foot pounds of torque and these heads flow between 45 and 50 cfm better and the intake was cut, welded and ported, I am expecting an easy 75 hp gain. I just have not gotten to the dyno to get a number yet. Jody Quote Link to comment Share on other sites More sharing options...
buZy Posted June 17, 2007 Share Posted June 17, 2007 jbc3, it's safe to say running 10's your car is wicked FAST! IMO those MM stubbies held up pretty darn well for how much torque has been applied to them. Another "consumable" item Quote Link to comment Share on other sites More sharing options...
jbc3 Posted June 17, 2007 Author Share Posted June 17, 2007 Yes, another consumable item... that's a good way to look at it. Fortunately the 4th gen f-body rear brake set-up will retain the broken stub in the bearings, unless I am doing some crazy sideways stunt. I will surely be pulling the other axle at some point soon, and inspecting it for any obvious stress. Jody Quote Link to comment Share on other sites More sharing options...
Z-Gad Posted June 17, 2007 Share Posted June 17, 2007 WOW, thanks for the photos... Now, I will wait to see what Ross has to say regarding the breakage. Mike Quote Link to comment Share on other sites More sharing options...
v80z Posted June 17, 2007 Share Posted June 17, 2007 I was just going to ask" What does the other side look like?". It is always amazing to me to see hardened materials fail. It appear there was a large amount of plastic deformation prior to the catastrophic failure. Was this driver or passenger side. What diff do you run LSD/WELDED/OPEN? You know I wonder why it twisted there rather than the CV shaft axle going into the diff. I wonder if the cv shaft splined portion is starting to show the same deformation. More pics as you get time please. Interesting stuff. Joe Quote Link to comment Share on other sites More sharing options...
pallnet Posted June 17, 2007 Share Posted June 17, 2007 From what I understand that is a weak spot on the Z's even when useing stock parts and driving a little harsh. Anything can break and it's always possible for things to be made and have one or so production flaws. From this post I don't gather that Ross is being bashed and as it's been said, This is the first I've heard of one breaking. Ross makes some fine products. We all know that the parts makers are not fighting over the chance to make parts for old Z's. Quote Link to comment Share on other sites More sharing options...
jbc3 Posted June 18, 2007 Author Share Posted June 18, 2007 This broken axle was on the passenger side. I am running an R230 rear with Moser axles (Modern Motorsport supplied also)... you know, what is listed in my sig . I have not pulled the CV's apart, but they are tight and have no obvious backlash. Quote Link to comment Share on other sites More sharing options...
v8dats Posted June 18, 2007 Share Posted June 18, 2007 wow! good job! that is some serious torque! add wide tires and traction. and i suppose that the tires werent wet? boom is right! Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted June 18, 2007 Share Posted June 18, 2007 Considering ths speeds that some guys are running on these axles I'd say ANY failure ought to be brought to light. No one is bashing Ross but if I was running a set of these at speed and wasn't made aware of a failure upset wouldn't even begin to express how I'd feel! It looks like it might have failed out nead an end, hard to put the pics together in my mind, but if that's so is it possible there wasn't deep enough spline engagement? Or did it fail back at the root? Would be helpful to see the parts laid out - been awhile since I've ripped the rear out of my car heh. Hopefully there's some measure that can be done to help prevent this in the future, this was certainly a pretty extreme example of stress! Any nitrous used while running these? Quote Link to comment Share on other sites More sharing options...
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