Glenwood
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That's what I replaced in my 63 housing. They were not welded in.
Chrysler 8 3/4 Axle bearing and Seal R&R...A How To
- Thread starter threewood
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That's what I replaced in my 63 housing. They were not welded in.
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Was thinking they are very similar if not just like the axle retaining plate studs. Been a very long time since totally removing the studs from a housing....
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I thought I was going to have to replace a couple of them a couple of years ago. I believe the FSM says to torque them to 45 ft lbs. Well when I first installed my center section I could feel them stretching at 40 ft lbs. Stopped right there and started a search on this. I found threads where guys were snapping them off trying to torque them to 45 ft lbs. Ended up using 30 ft lbs to 35 ft lbs. Pass it on!
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A grade 8 is in the high 40's and kinda doubt these are even gr 5's. Mine are done with a 3/8ths drive regular handle ratchet and might see 30. Never had a problem like that. Seem to remember using a torque wrench once just to get a feel for them....
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FYI....
The Tensile strength of grade 8 bolts/studs is:
150,000 lbs. per square inch
Grade 8 bolts are designated as a 150 ksi. This means its tensile strength or the resistance it has before it is subject to breaking under tension is equal to 150,000 lbs. per square inch.
One KSI or Kips per square inch = 1000 PSI.
The torque value is dependent on size and grade of the fastener and bolt involved. For example, all 1/2" dismeter bolts no not have the same maximum torque, tensile strength or yield point.
Not to get "preachie", but the torque value and the YIELD point of the fastener, referred to previously as "stretch" are similar terms but related to the grade of the fastener used.
To determine the yield point, or stretch, of a bolt or stud, a fastener of the size you want to use is tested by simulating a bolting application. A bolt is placed in a plate with just the threads exposed an threading on a corresponding nut and to begin tightening the nut with a beam style torque wrench. Continue to tighten the nut, until the the torque increases to the point where the torque required to turn the nut stops increasing. The bolt is now at its yield point. To be safe, take 70% of this torque reading as the maxinum value the particular diameter and grade of fastener should be torqued to. Thread pitch, coarse threads vs fine threads, in addition to bolting material also influence in clamping force of the fastener can provide.
There are several different interpretations with regard to the diameter and grade of the fastner and corresponding nut, on the intetnet. If you're curious as to the derivation, I would be happy to show and explain the differences. Just my opinion of course.
BOB RENTON
The Tensile strength of grade 8 bolts/studs is:
150,000 lbs. per square inch
Grade 8 bolts are designated as a 150 ksi. This means its tensile strength or the resistance it has before it is subject to breaking under tension is equal to 150,000 lbs. per square inch.
One KSI or Kips per square inch = 1000 PSI.
The torque value is dependent on size and grade of the fastener and bolt involved. For example, all 1/2" dismeter bolts no not have the same maximum torque, tensile strength or yield point.
Not to get "preachie", but the torque value and the YIELD point of the fastener, referred to previously as "stretch" are similar terms but related to the grade of the fastener used.
To determine the yield point, or stretch, of a bolt or stud, a fastener of the size you want to use is tested by simulating a bolting application. A bolt is placed in a plate with just the threads exposed an threading on a corresponding nut and to begin tightening the nut with a beam style torque wrench. Continue to tighten the nut, until the the torque increases to the point where the torque required to turn the nut stops increasing. The bolt is now at its yield point. To be safe, take 70% of this torque reading as the maxinum value the particular diameter and grade of fastener should be torqued to. Thread pitch, coarse threads vs fine threads, in addition to bolting material also influence in clamping force of the fastener can provide.
There are several different interpretations with regard to the diameter and grade of the fastner and corresponding nut, on the intetnet. If you're curious as to the derivation, I would be happy to show and explain the differences. Just my opinion of course.
BOB RENTON
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@RJRENTON Are you familiar with a product call Supertanium from Lawson Products? The company came out to the plant machine shop some years back and put on what I thought was a pretty good seminar and showed us how torque was applied and tested. Since our machine shop shared the same building as our disassembly and assembly section, we all attended. After all, we were trained to do it all including compressor work.....and I ain't talking about little compressors. They also showed how a cap screw and a nut performs when torqued multiple times. It was interesting. We knew they were coming so I brought in some fasteners that I was using from ARP and local hardware stores. Was a bit surprised to find that a rod nut gives up way before the rod bolt does and that pretty much applies to most nuts. I still have their fastener assembly handbook with all the charts. It also shows torque specs for dry and lubed and what slicker lubes do to the torque values.
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I've used the Supertanium Products before. Yes, the have a nice presentation and their products work quite well. With regard to the sometimes needed nuts, the best ones are called heavy hex nuts, where the wall, height and alloy correspond to the bolt it is used with. Heavy hex nuts, because off their construction, resist flattening under high clamp loads (high torque).
My only objection to the Supertanium Products was, when trying to use their products in an ASME CODE pressure vessel (boiler), where I had to produce documentation for the Material Certification and Traceability Requirements (heat composition of the bolt/nut used in manufacturing the item), they said the alloy and heat treatment specs were proprietary and would not be available. AWS D1-1 specs are more lenient. Holoochrome hardware is another good fastener to consider.
The choice of fastener to use in a specific application, and its installation torque values must be or should be strictly followed to provide the best way to insure a successful installation or repair. Just my opinion of course.
BOB RENTON
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With regard to your comments about industrial compressors, i have much experience with 3000 HP 4 stage double acting hydrogen gas compressors used the hydrogenation process of making food based oils to solids as in making Crisco. The 4th stage of the compressor exhaust pressure approached 2500 psi @ 2000+° F, which required both high tensile strength high alloy bolting hardware to survive the conditions. Upon disassembly of a high pressure (and interstage) connections, the hardware was discarded and new hardware was used upon reassembly. Hardware failure was not an option. However, the biggest issue was the short life of the 4th stage exhaust valves, due to the hi temps and pressures, even though the cylinders, valve seat areas were liquid cooled (not water). Hardware is also an important consideration in the waste gas (exhaust) side of a gas turbine feeding a waste heat boiler because of thermal cycling leads to hardware failure. Yes.... hardware is important consideration.
BOB RENTON
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threewood
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This thread just turned into a Science Journal article 
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Listen or read and learn.....you ain't heard nothin' yet......This thread just turned into a Science Journal article
BOB RENTON
66 Sat
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I've got a leak on my car and think it's this axle seal. It is running down the back of the tire, through the drum. I was hoping it was a brake cylinder but that looks dry. Does it look like the seal is leaking from the photo below? I've never tackled the rear end before but I'm keen to try. I'll probably replace the other non leaking side for peace of mind, if the first side goes according to plan.
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threewood
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Just looking through, I forgot the axle bearing / race part numbers....
WRONG PICTURE!!!! Those are carrier bearings, sorry.
WRONG PICTURE!!!! Those are carrier bearings, sorry.
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I'm barely rated as a shade tree mechanic and the axle seals are doable. Service manual helps, and lots of YouTube videos, too.
I'm going to man up and pull the axles and 3rd member on mine soon. I did call in some help for getting the 3rd member out.
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Yup, looks like an axle seal isn't doing it's job. Also you might replace the outer seal. It's just mainly to keep the grease on the bearings from getting out and any dirt getting into them. The outer seal can't be replaced without removal of the bearings though....
66 Sat
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Yeah it's all fixed now thanks, did the inner and outer seals and new bearings too. Rebuilt the drum brakes on both sides, set the end play, followed the advice on here, learned a lot.
flyingfeathers
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just for my own info in the 8 3/4 axles what years did the change of the diameter of the axle shaft from 1 5/16 diameter all the way thru to tapered 1.41 to 1.31,
29 spline
29 spline
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Don't know about pre 66 all that much but from then on, all 8 3/4 axles are 30 spline....just for my own info in the 8 3/4 axles what years did the change of the diameter of the axle shaft from 1 5/16 diameter all the way thru to tapered 1.41 to 1.31,
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And all of the axles that I've seen with a twist, the twist was in the splines but it's still a good idea to scribe a line done the entire length of the axle if you are worried about twist.....
440 Charger
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Thats true lol.Hey man, don't give away the ending!
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