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dynatrac hub tempertures?

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after installing newbearing after failure from water contamination i felt the outside of hubs after about 30 miles on highway. both sides are pretty warm to touch. i didn't get temp reading with thermo gun. its about 80 outside... hot hot do these thing get normally? bearings are packed with grease and tightened to spec(which ends up being around hand tight) thanks,
 
bearing buddies on dynatracs? i thought these were for trailers? i will check with temp gun to see what they are running at
 
My Spyn Tec's are "warm" after a 30 mile trip in 95F weather. The pain threshold is 120F for most folks. If you can hold your hand on them for several seconds with no discomfort - your good. If not then you might want to ck actual temp.

Bill
 
I just finished installing my Dynatrac hubs and after a test drive I could bearly keep my hand on the hub. I called Dynatrac tech support and he replied that if my hand didn't blister then more than likely they were ok. On installation I had only backed off the inner nut a 1/8 turn after tightening to 50 ft. lbs. , so I went back in and re-torqed to 50 lbs. then backed the nut off a quarter turn and now they stay cool.
 
One thing to keep in mind when you set up the bearings is that tightening the lock nut will also tighten the bearings beyond where you set them with the inner nut. As the lock nut is tightened, it takes up any play in the threads between the adjusting nut and the spindle, thereby making the bearings tighter than you thought they were.
 
I just finished installing my Dynatrac hubs and after a test drive I could bearly keep my hand on the hub. I called Dynatrac tech support and he replied that if my hand didn't blister then more than likely they were ok. On installation I had only backed off the inner nut a 1/8 turn after tightening to 50 ft. lbs. , so I went back in and re-torqed to 50 lbs. then backed the nut off a quarter turn and now they stay cool.
Interesting. I also back mine off 1/8 of a turn thinking that since they were new it might loosen a bit. I was planning back off 1/4 turn when I repack. My hubs get very warm but not too hot to hold you hand there.
 
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I run mine 1/4 turn loose... for the reason mentioned by rscurtis. I've never had my hubs too warm to touch, and as I stated above; most times they are less than 100*F using an IR thermometer. In the winter, they won't even reach 50*F.

One thing to keep in mind, the quality of grease used can also affect temperatures... I've seen this in my own setup.
 
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Ran into this problem when reinstalling my EMS hubs after ebuilding my front end. There recomended torque was way too tight. I just ended up doing it by feel. Made sure i could turn the rotor by hand with about 20 lbs of force. So far so good.
 
thanks for help guys,, when i installed bearings, i also set nut to 50 lbs, backed off full 1/4 turn. then set nut hand tight. i can hold my hand on the hub no problem so i guess i'm good! thanks again!
 
A while back there was an article on wheel bearing failures the number one cause was not enough pre-load. if there is too much play the wheel is allowed to wobble, and chatter thus taking out the races. This was on over road trucks. On Volvo and MerCruiser outdrives the in put shaft has bearings the same as our wheel bearings two cup/cone roller bearings. They are tourqued so that the bearing has a pre-load. The end result is 12 in Lbs rolling tourque for new bearings and 5-7 in Lbs rolling tourque for used bearings. Our trucks call for tourqueing the first nut to 40 Ft Lbs then back off 1/8 or until the locking tab can be inserted. Then the outer nut (Jam nut) tourqued to 40 ft Lbs. I've used this method on all wheel bearings with out any failures. Yes they some times run a bit warm when first set but after the bearings seat everything is nice and cool. That said I had a Suzuki side kick many years ago and I quote the manual thhe wheel bearings were turqued to 95 ft Lbs! then backed off the 1/8 and then the lock nut installed to the same tourque. When I did this the special Suzuki socket dam near sheared off... . But the wheels rolled nice and smooth with very little heating...
 
IIRC, the rule of thumb with tapered roller wheel bearings is that a little bit loose is FAR preferable too a little bit tight. Certainly, like EDankievitch points out, much too loose can lead too wobble and race pitting, but too tight WILL lead to axle overheating and metal fatigue. Also, IIRC, the technique with most of these bearings is pretty much the same...
over preload to set them (spin by hand a few times) and then back off in order to be able to be able to move the thrust washer with gentle pressure with a flathead screwdriver.

All that being said, there is nothing better then just right, installed to specs !!
 
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