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torque

flexjay87

NAXJA Forum User
Location
iowa city iowa
just installed a new set of bearings on my high pinion d-30 non disconnect pinion shaft and torqued the nut to 230 lbs., vs. the correct torque of 210 lbs. my fault, but what should i do, remove nut and install new one at correct rating or leave it? inch pound wrench showed about 25-30 drag, bearings were still dry though when we checked .
 
Get a new crush sleeve and start over.

Where did you get the information that 210 foot-pounds is the "correct" torque? That's not how the factory manual tells you to check it. With a new crush sleeve, you torque the nut until the resistance to turn the pinion reaches a specified number of inch pounds (the pre-load). I don't remember off-hand what the number is, but I think it's 15 inch-pounds. The FSM does NOT specify a foot-pound torque for the pinion nut.

For replacement of the seal the FSM says to measure the rotating torque before disassembly, then after reassmbly to torque to 5 inch pounds more. For new bearings, I'm pretty certain they want you to use a new crush sleeve and start from scratch. I think you have yours much too tight.
 
Are you checking the drag with the brakes (rotors/calipers) on?
Did you replace the bearing or just the seal?
 
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we put on the whole pinion rebuild kit, bearings shims,etc.,etc. i trashed my old set of bearings, water damage, and excess vibes from d-shaft. had axle shafts ,carrier out, brakes off , the whole nine yards.
 
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Been awhile since I did a shimmed dana, but seem to remember the pinion nut torque, doesn´t have whole lot of effect on the bearing preload, that´s adjusted by the shim thickness. But crush sleeve or no, I measure the preload, before disassembly and seem to remember mine being around 10-15 inch pounds, after reassembly.
I usually set the carrier bearings at near zero pre load and my stuff hasn´t overheated or eaten any bearings yet. Too loose they get noisy, irritating but rarley fatal. Too tight and they get hot, turn blue/or black and eventually self destruct.
As a last test, I turn the yoke with three fingers, some resistance, but not really enough to strain your fingers. If it´s too stiff, you can almost feel the bearings, roll over (almost feel a rythm to the rotation). If the pinion has any side movement (at the yoke), it´s too loose.
Got to remember, the bearings expand as they heat up.
Some of the guys on the modified board may have some more tips, they do a lot more gear changes. I just change my bearings out a couple of times a decade.
I do a lot of industrial gear boxes, I set my stuff up by feel. And if I make a mistake, I try to make it to the loose side, more than the tight side. Though a slightly tight bearing, will usually wear in, before it overheats and self destructs. I´m a big fan of the fingure test, if the area around the bearing gets hot enough to burn/blister your finger somethings not right.
 
scott w said:
i have the non crush sleeve style, sorry i didn't make that clear.
MY BAD!

You did say D30, but my brain was visualizing D35.

Sorry!
 
25-30 in/lbs. is at the high end of the spec for new brgs. No oil on them definitely makes a difference so they will be fine once lubed. The pinion nut as long as its tight enough will be fine. It can't be overtorqued, at least from the aspect of brg. preload.
 
8 mud and Explorer. thanks for your input.seems like things will be ok as is hopefully. i think the preload was a little high due to no lube yet in axle. i know one thing, i am seriously goin to price out those axle tube seals, the ones that go at the knuckle end. i always have some serios crud inside the axle tubes, good old midwest mud. Scott
 
You´ll probably be OK, but if your worried (I would be), check the temp with your fingure periodically. Might want to jack it up in front and turn the driveshaft and get a feel for it. Then periodically jack it up and give the driveshaft a spin. It would be best to check after a say 10 mile highway run.
I´m a fan of molybidilium (sp?), leaves a micro coating of black snot on the gears (not to be used with clutch type gear boxes). I usually dip the bearings in synthetic motor oil, grease, STP or Moly assembly lube, whichever is handy, before reassembly. And put a finger full of grease on all the seals (between the ring seal and the spring). I once melted a new set of axle outer bearing seals, my assumption the axle oil would migrate, before friction had a chance to act, was false. They were leaking again pretty quick.
I´ve never had any trouble with the bearing changes I´ve done, but have seen some other guys have serious problems. Had one guy, pull into the shop, with his freshly rebuilt front squealing. Put it up on the rack and tried to turn the drive shaft by hand, then with a 14 inch monkey wrench on the yoke, then with a 2 foot extension on the monkey wrench handle, finally got it to turn with my whole wieght (185) hanging from the 2 foot cheeter bar. Sure glad that wasn´t my diff.
If you do a lot of mudding, I´ve had pretty good luck spraying bio degradable chain saw oil (I buy it in 5 gallon drums), on the trouble spots. I´ve got a undercoating spray gun, with a plastic tubing extension to get inside the frame and in the axle housings. The time it takes to spray, you save double in cleanup. Getting the mud off while it´s still wet is also helpfull.
WARNING, oil in a vapor is explosive.
Another good trick, is if you do get it cleaned up well, a brushed on coating of boiled linseeds oil (after it dries), leaves almost a shiny varnish type coating on everything, that sheds mud pretty well. I try to get it really clean, at least a couple of times a year, so the salt doesn´t stay in the mud and start rot. Most undercoating is a waste of time, though I have found the stuff detailers spray on there motors to make them shine, works well for shedding mud. Toreson (Hinkle/Loc Tite) makes a undercoating primer, that also works well (reminds me of Shellac). Shellac, boiled linseed oil and bio degradable chain saw oil are environmentally friendly, why not?
I´ve packed a ring of grease soaked hemp rope in the end of the axle housing around the axle. Which worked well, when it stayed put, about 80% of the time. Kept the mud out and polished my axle a little. The bearing seals, for the old model T were grease soaked hemp or felt, later graphit impregnated cotton rope (low tech.).
 
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New pinion bearing preload on a dana 30 is 12 to 15 inch pounds. 25-30 is way too high (dry or not), and will heat and eat the new bearings. With the shimmed pinion, just back off the pinion nut, reapply lock-tite and retorque till you get the preload you need. If you are missing or have too many shims you might need to adjust the pack to get a torque spec you are happy with and the preload that's good for the bearings. Shoot for a min of 180 ft lbs or so on the pinion nut.
 
I just looked in a 93 FSm and the pinion preload table for 30 and 35 said. New bearing 20-40 inch pounds (the bearings aren´t perfect and will wear in some), old bearing 10-20 (they are as round as they are gonna get) and 8 1/4 " ring gear 10-20. My old Dana manual (from the 80`s) says all Dana through 70 series 15 to 30 inch pounds. I read farther into the manual and it says for the 9 1/4 and 10 1/4 10 to 20 old bearing and 20-40 with new bearings.
I doubt many inch pound torque wrenches have been calibrated lately and are rarley perfect (especially at very low readings) when new.
The Spicer, light axle specifications manaual, says 15-30 inch pounds for the D 30.
 
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DaffyXJ said:
New pinion bearing preload on a dana 30 is 12 to 15 inch pounds. 25-30 is way too high (dry or not), and will heat and eat the new bearings. With the shimmed pinion, just back off the pinion nut, reapply lock-tite and retorque till you get the preload you need. If you are missing or have too many shims you might need to adjust the pack to get a torque spec you are happy with and the preload that's good for the bearings. Shoot for a min of 180 ft lbs or so on the pinion nut.


Where did you find those specs? Different manuals vary, but 12-15 is usually the low end in any book I've seen. 30 in/lbs is tight, but if everything is clean, won't create a problem. Just go easy on the break in.

The whole point of the preload shims is that they set the preload. If its too tight when the nut is tightened down, it needs more shim. You can't just back off the nut and then only tighten it partially. Loctite or not, this is not the proper procedure.
 
hey guys, i was lookin through my manual earlier tonight and found the same info as 8mud. 20-40 preload on new bearings and around 15 for used. anyhow i called Randy's r+p and they said factory manual for new bearings are high in their opinion. guy i talked to said the newer the axle ( mines an 87) the more problems they had with burnin up bearings. his "safe suggestion would be to back it off, but i may be ok? seems there were some communication problems between Dana and Jeep, on just what the preload should be, gee imagine that! i'm gonna keep an eye on mine, book says 20-40 and mine read that bone dry. if i see or sense any problems i will have to yank it back apart. heck i might just leave my driveshaft out unless i'm wheelin for a while..... and see what happens.
 
40 in/lbs. is definitely high as far as I'm concerned, and I wouldn't set them that tight intentionally. But I've also checked preload on used ones that were in the 25 range w/ no apparent problems. I usually ended up around 20 doing them by feel when I was setting them up regularly. Now, I don't do them much and check them w/ torque wrench. I've kinda lost my feel.
 
yeah 40 is the high end in the book and i was well below that, hopefully much less with lube in there and a little break in time.( i hope break is not the key word) just a little humor therer since it hasn't broken yet, i guess time will tell? thanks for your time.......
 
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