2126 Posted March 15, 2007 Share Posted March 15, 2007 The person who did that is really stupid. Why you wouldn't spend $50 and have some shouldered ring gear bolts made, or better yet, get the right carrier in the first place is beyond me. I wouldn't base any decision I made on some random moron's good fortune. Not trying to get bitchy about it, but that's a pretty damn stupid thing to do. So Jon, I'm very surprised you would call Precision Gear morons and stupid!!! So why didn't you use shouldered ring gear bolts and or use the right carrier....so, I guess it's safe to assume you are also stupid and a moron. Jon, I don't really think your a moron or stupid, I'm only trying to make a point about the un-necessary spacers when using 10mm ring gear bolts and ring gear on a carrier intended for 12mm ring gear bolts and ring gear. As I said before....I think Precision Gear knows what they are doing, based on experience. I still respect you Jon!!!! Tom Link to comment Share on other sites More sharing options...
blairjj Posted March 16, 2007 Share Posted March 16, 2007 I'd like to offer the following for your consideration: http://en.wikipedia.org/wiki/Bolted_joint I could reference more technical docs but I think Wikipedia did a nice job one this one. Jay Link to comment Share on other sites More sharing options...
JMortensen Posted March 16, 2007 Share Posted March 16, 2007 So Jon, I'm very surprised you would call Precision Gear morons and stupid!!! So why didn't you use shouldered ring gear bolts and or use the right carrier....so, I guess it's safe to assume you are also stupid and a moron. Jon, I don't really think your a moron or stupid, I'm only trying to make a point about the un-necessary spacers when using 10mm ring gear bolts and ring gear on a carrier intended for 12mm ring gear bolts and ring gear. As I said before....I think Precision Gear knows what they are doing, based on experience. I still respect you Jon!!!! I'm not running the freakin Baja 1000. My project is extremely budget limited, and if I was running races of that caliber you can be assured that I would have found a ring and pinion set with 12mm holes and run it instead. That's the kind of race and the kind of punishment where EVERYTHING counts. On my car if it breaks I'll pull my truck in front of it, put it on the trailer and tow it home. A little different. Link to comment Share on other sites More sharing options...
lbhsbZ Posted March 16, 2007 Share Posted March 16, 2007 If I was running the baja, I'd use a Ford 9" or bigger Thats just me though. Both answers are correct. AFAIK, The ring gear is designed so that the bolts, loaded in tension only, provide enough friction between the ring gear and the diff to keep everything in place so that bolts are never loaded in shear. But, if enough load is put on the ring gear to overcome the amount of friction between the ring gear and diff, then they will spin indepenently and load the bolts in shear. Now the question....since the bolts aren't supposed to be shear loaded anyway, does it matter if they are loaded by a steel spacer or a cast diff? I dunno. Link to comment Share on other sites More sharing options...
wheelman Posted March 16, 2007 Author Share Posted March 16, 2007 I said I'd update this thread once I installed the ring gear so here goes. Edit: The measured backlash on my open diff was .007". My ring gear did have a fairly tight interference fit with the open diff so took a bit of persuading to remove. It also has a good tight fit with the LSD. There were no alignment issues from the hand made shims I used, all the bolts threaded right in with no binding what so ever. Now I'm waiting to receive the bearings so I can finish the swap. I can hardly wait. BTW: I never meant to restart the argument about the need for spacers, sorry to wack that hornets nest. Wheelman Link to comment Share on other sites More sharing options...
Guest TurboHatch Posted February 1, 2010 Share Posted February 1, 2010 sorry to bring back from the dead but i am getting some spacers made as we speak and i need to know the exact length, i understand the length will be on the short side and thats fine i just dont want to have them made to long. by the way i can have extra made and post them up in the classifieds, sure will be cheaper then that mc masters price lol. Link to comment Share on other sites More sharing options...
Gregmatic Posted February 1, 2010 Share Posted February 1, 2010 I made a quick writeup for those inclined to know. This will wrap this thread up: http://www.z31performance.com/forum/viewtopic.php?f=3&t=14753&hilit=12mm+spacers See? You can learn something from Z31P once in a while. Although it is usually the other way around Link to comment Share on other sites More sharing options...
Guest TurboHatch Posted February 1, 2010 Share Posted February 1, 2010 I made a quick writeup for those inclined to know. This will wrap this thread up:http://www.z31performance.com/forum/viewtopic.php?f=3&t=14753&hilit=12mm+spacers See? You can learn something from Z31P once in a while. Although it is usually the other way around I already read your write up or maybe it was one you copied or some one that copied you not sure but its the exact same down to the pics and its one of the reasons that prompted me to ask for better info you say they are 12mm in length and need trimmed a couple mm sooo is 10 mm the proper length with out a doubt? some people use the word "couple" loosely. like i said i am cutting these and dont want to have to do it twice. Link to comment Share on other sites More sharing options...
Gregmatic Posted February 1, 2010 Share Posted February 1, 2010 yup,take off like 2mm on each one with a dremel. Easy. Link to comment Share on other sites More sharing options...
JMortensen Posted February 1, 2010 Share Posted February 1, 2010 Can't see the link, but didn't we establish that there is a bronze mcmaster.com 12mm OD x 10mm ID x 12mm length bushing that pops right in and doesn't need screwing with? I believe it was this one... http://www.mcmaster.com/#6679k14/=5mo30r Link to comment Share on other sites More sharing options...
Guest TurboHatch Posted February 1, 2010 Share Posted February 1, 2010 Can't see the link, but didn't we establish that there is a bronze mcmaster.com 12mm OD x 10mm ID x 12mm length bushing that pops right in and doesn't need screwing with? I believe it was this one... http://www.mcmaster.com/#6679k14/=5mo30r Good question, and the reason why I am asking around, it seems that every article i read on these bushings claims they come 12 mm in length and need trimmed a "couple" mm. however I have come across a post or two that suggest they are fine as is. The discrepancy is what i am trying to clear up so I and future readers wont have to sift threw hours of searching like I am having to do. Link to comment Share on other sites More sharing options...
JMortensen Posted February 1, 2010 Share Posted February 1, 2010 I think you're making it worse for people down the line trying to search and find the answer. I haven't seen anyone say anything about trimming prior to this. I'd suggest you actually buy the spacers, stick them in the carrier and make sure they don't protrude out on either side. So long as the spacer is equal to or narrower than the carrier flange, no problem. http://forums.hybridz.org/showpost.php?p=982194&postcount=54 Link to comment Share on other sites More sharing options...
JMortensen Posted February 1, 2010 Share Posted February 1, 2010 HUH? your joking right? almost EVERY thread dealing with the mcmaster bushings all say they need trimmed. let me quote exactly for you. this quote is from z31 site. and the exact same information is here on this forum if you search for the subject. now I also found 1 fella who claimed he did not trim his.and i found another guy who claims he had to trim some. so once again full circle to the original question. I was hoping to get the spacers made before i had the rear tore apart so i am ready to go. obviously since It seems to be a conflicted answer i will be forced to make them after i have the rear apart and can measure once and for all. the bottom line is I am not making it worse I am making it better Its answers like yours that give 0 feed back to the real question at hand that litter up these threads and make it worse. you might as well told me elvis was spotted at mcdonalds because it would have had as much helpful information in that statement as your post did. please forgive me for assuming these datsun forums are a place to pluck valuable information from people who have already "been there and done that" I guess I am spoiled by all the other forums for other makes and models that i am a member on. Never been on any Z31 site, so I have no knowledge of that, but I'll take your word for it that people there are cutting down the spacers. That doesn't necessarily mean that it needs to be done. I've been in damn near EVERY diff thread on this forum in the last 5 years, and I have never seen anyone talk about cutting down the mcmaster spacers. So when you take an issue that has previously been pretty settled and bring in posts from another forum that bring things into question, I'd say you've muddied the waters. I just went and looked at my spare LSD, and marked the depth of the carrier. I then went to measure with my digital caliper but the batteries are dead. Eyeballing against a metric ruler it looks like right about 12mm. Tough to say exactly, but I can tell you that 10mm is shorter than strictly necessary without a doubt. If you would like to send some spacers to me I'll check them and let you know. Link to comment Share on other sites More sharing options...
JMortensen Posted February 1, 2010 Share Posted February 1, 2010 Then there's this. I know Dave was using the OBX, but he says: http://forums.hybridz.org/showpost.php?p=1120579&postcount=3 Link to comment Share on other sites More sharing options...
B00STDZ Posted February 2, 2010 Share Posted February 2, 2010 Im following this thread as well and am curious if trimming is required... Link to comment Share on other sites More sharing options...
JMortensen Posted February 2, 2010 Share Posted February 2, 2010 Im following this thread as well and am curious if trimming is required... Follow the link on my last post. Link to comment Share on other sites More sharing options...
B00STDZ Posted February 2, 2010 Share Posted February 2, 2010 Is that for the z31 clsd? Link to comment Share on other sites More sharing options...
B00STDZ Posted February 3, 2010 Share Posted February 3, 2010 I went ahead and purchased 10... Link to comment Share on other sites More sharing options...
260zman Posted February 5, 2010 Share Posted February 5, 2010 Jeez guys! they're only spacers for bolts. All i did (last week) for mine was used some 1/2"OD stainless tube which is just about 3/8" ID. i cut off the spacers 10mm long in my drop saw (nothing techo about this i know, but my lathe aint going right now), then linished the burr off the ends, used a bigger drill bit to remove internal burrs, and then pressed them (or use a vice/big hammer and anvil) into the 12mm holes. when linishing the ends, i put a bit of a lead in on one end to help guide the bush into the housing. The 1/2" tube is an absolutely perfect interference fit in the hole (1/2" = 12.7mm) and if they've been pushed in squarely, they wont require much for the 10mm bolt to go in. I think i had to ream 2 or 3 with a 10mm drill bit but that was about it. So there you go, it took me around 20-30 minutes all up to make them up, and i had no idea when i opened the diff up to swap ring gears -that i would have to make spacer bushes. Some people do try to apply rocket science to things that arent going to the moon. Link to comment Share on other sites More sharing options...
B00STDZ Posted February 5, 2010 Share Posted February 5, 2010 10mm-12mm long seems to be the length. If you were having them made i would do 10mm long. Link to comment Share on other sites More sharing options...
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