janaka Posted March 20, 2010 Share Posted March 20, 2010 Hey guys Yesterday, for the 2nd time, my driveshaft has loosened the nuts off the bolts while driving. Needless to say the vibrations weren't fun and I pulled over to inspect what the possible issues were and all 4 DS bolts were loose. I hand tightened them (whilst burning my wrist on my exhuast) and limped home. Threw it up on a jack and tightened the SOB's back down and the test drive went well. I'm looking to know what size of DS bolts you guys are using (I have an R200 rear end and JCI DS). At this point the threads are getting chewed up from this and feel better replacing them than trying to reuse them. Also I had a local race guy say that if I'm loosening the DS bolts I may have a driveline angle issue that is causing extra vibrations which is loosening the bolts off. Does this sound accurate as a potential cause for my problem? Any input is appreciated Thank you Jason Quote Link to comment Share on other sites More sharing options...
proxlamus© Posted March 20, 2010 Share Posted March 20, 2010 i had a similar issue.. even with loc-tite .. it was the weirdest thing. After a heavy inspection I found that my lock washers were no longer "locking" after being worn down over the years. May I also recommend a "stubby" 10 mm wrench.. it makes life much much easier =) Quote Link to comment Share on other sites More sharing options...
johnc Posted March 20, 2010 Share Posted March 20, 2010 Hey guys Yesterday, for the 2nd time, my driveshaft has loosened the nuts off the bolts while driving. Needless to say the vibrations weren't fun and I pulled over to inspect what the possible issues were and all 4 DS bolts were loose. I hand tightened them (whilst burning my wrist on my exhuast) and limped home. Threw it up on a jack and tightened the SOB's back down and the test drive went well. I'm looking to know what size of DS bolts you guys are using (I have an R200 rear end and JCI DS). At this point the threads are getting chewed up from this and feel better replacing them than trying to reuse them. Also I had a local race guy say that if I'm loosening the DS bolts I may have a driveline angle issue that is causing extra vibrations which is loosening the bolts off. Does this sound accurate as a potential cause for my problem? Any input is appreciated Thank you Jason They are M8 x 1.25P. If the threads are chewed and/or the bolts won't hold torque its time to replace them. Buy a good class 10.9 bolt (nothing from Home depot, Ace, etc. - go to an industrial supply house) of the correct grip length and then use metal locking nuts. Quote Link to comment Share on other sites More sharing options...
m1noel Posted March 20, 2010 Share Posted March 20, 2010 I had the same problem after the swap. I put in slightly longer bolts and used torque-biased locking nuts. Now no problems in 2 years. Quote Link to comment Share on other sites More sharing options...
mark Posted March 20, 2010 Share Posted March 20, 2010 I used aircraft hardware. The nuts are bolts are drilled for cotter pins that are placed after it is torqued down. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted March 20, 2010 Administrators Share Posted March 20, 2010 The locking nuts both JohnC and m1noel mentioned cured mine as well. Sometimes referred to as "prevailing torque" nuts. Not to be confused with the nylon style. They are all metallic and look pinched or crushed on one end. They work great on collector flange bolts as well. And yes, driveline vibration does seem to exaggerate the problem. Quote Link to comment Share on other sites More sharing options...
janaka Posted March 20, 2010 Author Share Posted March 20, 2010 Awesome guys, thanks for the help. There are a couple industrial supply shops here that I'll pop into on monday. I'll make sure that I get the metal lock nuts (I know what ones you guys are talking about, someone else was describing them). What kind of scared me was that my wife (8.5months pregnant) took the car to work the day before this happened to me (she only works 5miles from home thankfully). Car is out of commission now till I get these new bolts in. Stubby wrench is about the only way to get these tightened I'm convinced, having done this twice now...lol Quote Link to comment Share on other sites More sharing options...
Drax240z Posted March 20, 2010 Share Posted March 20, 2010 Take a cheap box end (full length) and grind down the profile so it fits... I'm convinced you can't get enough torque on them using a stubby. FWIW, I've used new factory hardware, nice and tight and never had issues. Solid diff mount too. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted March 20, 2010 Administrators Share Posted March 20, 2010 FWIW, I've used new factory hardware, nice and tight and never had issues. Solid diff mount too. Ah yes, but you have an L6. This problem is common with the Chevy swap. Quote Link to comment Share on other sites More sharing options...
Drax240z Posted March 20, 2010 Share Posted March 20, 2010 I wasn't going to mention that, wouldn't want to make the Chebby guys feel inferior. Quote Link to comment Share on other sites More sharing options...
janaka Posted March 20, 2010 Author Share Posted March 20, 2010 Take a cheap box end (full length) and grain down the profile so it fits... I'm convinced you can't get enough torque on them using a stubby. FWIW, I've used new factory hardware, nice and tight and never had issues. Solid diff mount too. I've been working out just for this reason. 21" pythons will git-r-done. Ok well not 21" but ... ah fack, I'm just havin' fun now. Thanks again guys Quote Link to comment Share on other sites More sharing options...
Drax240z Posted March 20, 2010 Share Posted March 20, 2010 Half the lever arm needs twice the force to get the same torque... even if you are stronger than average, you're probably not twice as strong. Quote Link to comment Share on other sites More sharing options...
janaka Posted March 20, 2010 Author Share Posted March 20, 2010 (edited) physics always beat smartass' oh and super moderators are NEVER wrong Edited March 20, 2010 by janaka Quote Link to comment Share on other sites More sharing options...
Drax240z Posted March 21, 2010 Share Posted March 21, 2010 super moderators are NEVER wrong We have a winner! First hybridz member to figure it out. You win... 23 seconds of ban immunity......... Well, time is up! Quote Link to comment Share on other sites More sharing options...
MoNkEyT88 Posted March 21, 2010 Share Posted March 21, 2010 When I dissassembled my 6 liter z I noticed that the driveshaft hardware had stretched or somehow loosened. 480hp > cheap hardware Quote Link to comment Share on other sites More sharing options...
johnc Posted March 21, 2010 Share Posted March 21, 2010 I used aircraft hardware. The nuts are bolts are drilled for cotter pins that are placed after it is torqued down. Uuuhhh, no. Not cotter pins, safety wire with a very specific wrap and twist. http://www.ultralightnews.com/pilotslounge/safetywire.htm Quote Link to comment Share on other sites More sharing options...
johnc Posted March 21, 2010 Share Posted March 21, 2010 Halfshaft bolts/nuts loosen from inadequate torque and vibration. The vibration comes primarily from the u-joints cycling but the type of differential also has an affect. A welded diff will loosen halfshafts nuts very quickly. Racers will check then after every session if they are running a welded diff. Quote Link to comment Share on other sites More sharing options...
MoNkEyT88 Posted March 22, 2010 Share Posted March 22, 2010 (edited) They sure are a pain to get at also. Are there any trick tools to make it easier to get at?? Edited March 23, 2010 by MoNkEyT88 Quote Link to comment Share on other sites More sharing options...
janaka Posted April 12, 2010 Author Share Posted April 12, 2010 well i finally got around to pulling out these bolts and putting in the new ones with the metal locking nuts. well holy snit, all 4 had the threads destroyed in the middle section of the bolts (worn FLAT) and 3 of 4 were slightly bent. These were fubar'd much worse than I ever imagined. The bolts themselves were stamped 8.8 on the top although I'm not sure if thats the grade rating or not but I'm glad that they were somewhat strong as to not have completely let go when they came loose when I was driving. Its scary when I look at them now. I took the car out and beat on it for a bit with the wife and all seems well. I'll probably put the car up this week to make sure that they are still tight just to be safe. thanks again to those who helped, a potential crisis was adverted. I'll try to post a pic of a bolt later on when I get a chance. jason Quote Link to comment Share on other sites More sharing options...
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