martinf Posted May 15, 2009 Share Posted May 15, 2009 Bear with me on the lack of correct terms here...I've got a 1965 B set up as a dump truck with bogie camelbacks. The caps that hold the trunion tube to the trunion stands( or do you call it supports?) have 4 bolts on each side of the truck...and they are marginally loose. One even has the head popped off. There's even some space between these bottom caps and the tops. Just to clarify here, I'm not tallking about the ubolts at the spring pads/perches.A couple of questions for you expert wrench spinners....Should I tighten or replace these bolts and nuts? They're pretty rusty and funky. What grade should I replace with?Could someone explain to me the function of these things that I am calling caps? Seems like they hold the trunion tube up against the stands. SInce the wieght of the truck bears down on the trunion stands and onto the tube, it seems like these only serve as to hold the trunion in place (and deal with the bouncing up of the suspension system when you went over a bump, for example. Is this correct?Thanks for bearing with my lack of correct terms and for helping me understand what purpose these serve and how to fix.~martin Quote 1965 Mack B-74, dump1974 Mack R, logging w/Prentice self-loaderwww.somewhereonthemountain.blogspot.com Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/ Share on other sites More sharing options...
MACKS Posted May 15, 2009 Share Posted May 15, 2009 You should replace the bolts with new ones,since one is already broke off you should do this as soon as possible,without those caps your tandem could separate from the truck,your gonna need to heat thaes bolts to get them off and any mack dealer will have the right bolts to put back on,if the inside of the caps are worn witch they most likely are replace the caps also or run a few beads of weld on them so they tighten up against the trunion bar. Quote Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35233 Share on other sites More sharing options...
theakerstwo Posted May 16, 2009 Share Posted May 16, 2009 and use grade 8 on ever thing on a truck unless it is hanging a fender on or holding a mirror on. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35251 Share on other sites More sharing options...
martinf Posted May 16, 2009 Author Share Posted May 16, 2009 Thanks for the info guys. And what should I torque those trunion cap bolts to?~martin Quote 1965 Mack B-74, dump1974 Mack R, logging w/Prentice self-loaderwww.somewhereonthemountain.blogspot.com Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35275 Share on other sites More sharing options...
Rob Posted May 17, 2009 Share Posted May 17, 2009 Thanks for the info guys. And what should I torque those trunion cap bolts to?~martin1250-1400ft. pounds sounds about right off the top of my head.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35298 Share on other sites More sharing options...
martinf Posted May 17, 2009 Author Share Posted May 17, 2009 1250-1400ft. pounds sounds about right off the top of my head.RobRob,thanks, and what is the official name for the thing I am calling a "cap"? Quote 1965 Mack B-74, dump1974 Mack R, logging w/Prentice self-loaderwww.somewhereonthemountain.blogspot.com Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35302 Share on other sites More sharing options...
Rob Posted May 17, 2009 Share Posted May 17, 2009 Rob,thanks, and what is the official name for the thing I am calling a "cap"?Spring insulator cap.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35304 Share on other sites More sharing options...
MACKS Posted May 17, 2009 Share Posted May 17, 2009 Spring insulator cap.RobRob, he is talking about the trunion caps,the two caps that have four bolts in each witch hold the trunion stands to the bar.I never used a torque wrench on them I just tighten them equally with a big air gun,you want the cap to go on straight so tighten each bolt a little at a time. Quote Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35305 Share on other sites More sharing options...
HK Trucking Posted May 17, 2009 Share Posted May 17, 2009 And he should also make sure to remove all loose rust & dirt from the mating surfaces of the caps and trunnion stands & shaft before installing the caps, or else they will loosen up again quickly as the rust & dirt sqeezes out during operation. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35309 Share on other sites More sharing options...
Rob Posted May 17, 2009 Share Posted May 17, 2009 Rob, he is talking about the trunion caps,the two caps that have four bolts in each witch hold the trunion stands to the bar.I never used a torque wrench on them I just tighten them equally with a big air gun,you want the cap to go on straight so tighten each bolt a little at a time.Don't know how I got off on that tangent..... Just broke a camelback suspension apart earlier in the week for rehab and was thinking of the rubber spring ends for some reason.Thanks,Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35313 Share on other sites More sharing options...
jeffbyrne Posted May 17, 2009 Share Posted May 17, 2009 Bear with me on the lack of correct terms here...I've got a 1965 B set up as a dump truck with bogie camelbacks. The caps that hold the trunion tube to the trunion stands( or do you call it supports?) have 4 bolts on each side of the truck...and they are marginally loose. One even has the head popped off. There's even some space between these bottom caps and the tops. Just to clarify here, I'm not tallking about the ubolts at the spring pads/perches.A couple of questions for you expert wrench spinners....Should I tighten or replace these bolts and nuts? They're pretty rusty and funky. What grade should I replace with?Could someone explain to me the function of these things that I am calling caps? Seems like they hold the trunion tube up against the stands. SInce the wieght of the truck bears down on the trunion stands and onto the tube, it seems like these only serve as to hold the trunion in place (and deal with the bouncing up of the suspension system when you went over a bump, for example. Is this correct?Thanks for bearing with my lack of correct terms and for helping me understand what purpose these serve and how to fix.~martinHi Martin, the stands that come down from the frame are referred to as a pedestal, the tube is called a spindle,some are hollow some solid, the trunnion slides on to the spindle. The spindle is clamped to the pedestal with the 4 bolts each side, there should be a collar between the pedestal and the spindle. Regards Jeffro Quote Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35340 Share on other sites More sharing options...
martinf Posted May 17, 2009 Author Share Posted May 17, 2009 quote name='MACKS' date='May 17 2009, 06:50 AM' post='35305']Rob, he is talking about the trunion caps,the two caps that have four bolts in each witch hold the trunion stands to the bar.I never used a torque wrench on them I just tighten them equally with a big air gun,you want the cap to go on straight so tighten each bolt a little at a time.That's it! Okay, so before I replace bolts, I'd like to understand a bit about what's going on here....The caps are downright loose. well, I can't shake them, but the bolts can be spun in the holes by hand.So how did the caps and bolts get so loose? And why is the opening between cap and trunion stands much bigger on the wheel sides than on the insides? Did something bad happen or is this normal for an old truck?And then regarding the fix. Since this truck is only used to haul stuff up on my ranch (not even licensed for the road), could I get by with just tightening up the bolts? And, since I'll need to use heat to persuade them, will that weaken them even more? (this sounds like a bad idea even as I write it!)And, if I could ask one more question, what's the proceedure here? It looks like I could take off all four bolts, drop the cap, wire brush clean/ weld beads if need be to tighten the slop up, put new bolts in and re-tighten. I'm assuming the trunion cross tube will stay put as long as the spring assemblies are all in place.thanks again[ Quote 1965 Mack B-74, dump1974 Mack R, logging w/Prentice self-loaderwww.somewhereonthemountain.blogspot.com Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35343 Share on other sites More sharing options...
HK Trucking Posted May 17, 2009 Share Posted May 17, 2009 quote name='MACKS' date='May 17 2009, 06:50 AM' post='35305']Rob, he is talking about the trunion caps,the two caps that have four bolts in each witch hold the trunion stands to the bar.I never used a torque wrench on them I just tighten them equally with a big air gun,you want the cap to go on straight so tighten each bolt a little at a time.That's it! Okay, so before I replace bolts, I'd like to understand a bit about what's going on here....The caps are downright loose. well, I can't shake them, but the bolts can be spun in the holes by hand.So how did the caps and bolts get so loose? And why is the opening between cap and trunion stands much bigger on the wheel sides than on the insides? Did something bad happen or is this normal for an old truck?And then regarding the fix. Since this truck is only used to haul stuff up on my ranch (not even licensed for the road), could I get by with just tightening up the bolts? And, since I'll need to use heat to persuade them, will that weaken them even more? (this sounds like a bad idea even as I write it!)And, if I could ask one more question, what's the proceedure here? It looks like I could take off all four bolts, drop the cap, wire brush clean/ weld beads if need be to tighten the slop up, put new bolts in and re-tighten. I'm assuming the trunion cross tube will stay put as long as the spring assemblies are all in place.thanks again[Just cut off the nuts, drive the bolts out, clean up any loose rust & dirt from the trunnion shaft and the caps, then reassemble with new grade 8 fine thread bolts and tighten the sh*t out of the bolts & nuts.Now that I've seen a picture of the stuation, I notice there is still a gap between the cap and the trunnion stand, so there's no need to weld on anything to "take up the slop".Tightening the new bolts should pull it all together quite nicely. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35345 Share on other sites More sharing options...
martinf Posted May 17, 2009 Author Share Posted May 17, 2009 Great, thanks, that's what I'll do.Any thoughts as to how they got so loose?~martin Quote 1965 Mack B-74, dump1974 Mack R, logging w/Prentice self-loaderwww.somewhereonthemountain.blogspot.com Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-35346 Share on other sites More sharing options...
mudslut28 Posted August 26, 2009 Share Posted August 26, 2009 LOL I know this is an old thread but I havent been here for a while. Does it look to anyone else like that saddle is toast also? Quote Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-39610 Share on other sites More sharing options...
Rob Posted August 26, 2009 Share Posted August 26, 2009 LOL I know this is an old thread but I havent been here for a while. Does it look to anyone else like that saddle is toast also?From the angle of the photo it does appear that the mating surface is "scrubbed off" a bit on the inside. This may or may not be a factor as those surfaces are not a load bearing member when the bushings are good. Cracks are what I've replaced the lower saddles for. I believe is the main reason for replacement in the shops.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9398-trunion-bolts/#findComment-39614 Share on other sites More sharing options...
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