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I just serviced my trailers, 5 axles in all, for the year (hopefully). On a few of the wheels the castle nut fell perfectly on the cotter pin hole such that I either had to back off or go forward which adds a smidge of preload to the bearings. Backing off leaves the tiniest bit of wobble in the wheel so I opt for a little preload instead. Just curious what others do.
 

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If you pre-load, the bearing assembly will expand due to heat from use,,,
the expansion will force all the grease out of the bearing, the bearing will fail.

Bearings will not work without a film of lubricant.
 

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PHP:
I guess we'll see what the bearings look like next spring
On my pj trailers they say to torque to a certain ft. Lbs. don’t remember the exact value but around 55lbs I think. Then loosen and turn nut to touch again and put in closest castle nut slot. Closest is maybe not the correct term. Go backwards to the first is a better term, if it is close to the next one that is fine if you can get there with your finger. If you need a tool that is too tight.
 

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From the Timken book!!!!

MANUAL BEARING SETTINGManual methods are frequently used to set bearings on avariety of equipment with low to moderate volume productionrequirements whereby a non- exact, primarily end play, settingrange variation is acceptable. No special tooling, gauges,charts or fixtures are typically required, but assembler’s skilland judgment are necessary. For example, in the case of aconventional truck non-driven wheel with a single adjustingnut design (Figure 3), manual setting involves tightening theadjusting nut while rotating the wheel until a slight bind is felt.Then the adjusting nut is backed off 1/6 to 1/4 turn to the nearestlocking hole or sufficiently to allow the wheel to rotate freelywith some minimal end play. The adjusting nut is then locked inthis position. Skill and judgment are required to determine whenthe wheel binds slightly in rotation. The more complicated theequipment and/or the larger and heavier it is, the greater degreeof skill and judgment required.

https://www.timken.com/wp-content/uploads/2016/10/5556_Bearing-Setting-Brochure-1.pdf
 

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I’ve always preloaded. Torque to spec while spinning. Back it off to next hole. All of the aviation schools and everything I’ve been taught ha aligned with that procedure. Never had a bearing failure associated with it. :unknown:

I have seen loose bearings cause issues though....
 

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From the Timken book!!!!

MANUAL BEARING SETTINGManual methods are frequently used to set bearings on avariety of equipment with low to moderate volume productionrequirements whereby a non- exact, primarily end play, settingrange variation is acceptable. No special tooling, gauges,charts or fixtures are typically required, but assembler’s skilland judgment are necessary. For example, in the case of aconventional truck non-driven wheel with a single adjustingnut design (Figure 3), manual setting involves tightening theadjusting nut while rotating the wheel until a slight bind is felt.Then the adjusting nut is backed off 1/6 to 1/4 turn to the nearestlocking hole or sufficiently to allow the wheel to rotate freelywith some minimal end play. The adjusting nut is then locked inthis position. Skill and judgment are required to determine whenthe wheel binds slightly in rotation. The more complicated theequipment and/or the larger and heavier it is, the greater degreeof skill and judgment required.

https://www.timken.com/wp-content/uploads/2016/10/5556_Bearing-Setting-Brochure-1.pdf
Apparently skillandjudgment arenot required to writ theyer manuals.

Maybe the writer was preloaded...:bigbeer:
 

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Torquing the adjustment nut while rotating the wheel is performed to displace grease grease between the spindle and the inner bearing races and to seat them on the spindle. Backing off the nut after that is to remove the preload. Often, the shop manuals will also provide and end play specification if your not comfortable with your skill and experience level.
 

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I've never added preload to a wheel bearing. Normally, I torque the nut to a certain spec, then back off the nut about 1/8-1/4 turn. If the bearing nut is too snug, there's a chance that the bearing will build heat and sling the grease out.
Same here, I rotate the tire/wheel as I tighten, to 50lb-ft, then back of between 1/8 to 1/4 turn, to a lock position. If it feels too loose, I tighten again to 50lb-ft and back off the 1/8 - 1/4 turn.
 

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I’ve always tightened the nut with channel lock pliers while rotating the hub assembly with other hand until snug. Stop turning hub, back nut off with pliers then hand tighten nut. If cotter pin hole doesn’t line up always back off the nut to first alignment hole. This is the method my dad showed me many years ago and after hundreds of bearings over the years no failures (knock on wood!). I think any preload on a trailer bearing is bad as there is no room for heat expansion.
 

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I’ve always tightened the nut with channel lock pliers while rotating the hub assembly with other hand until snug. Stop turning hub, back nut off with pliers then hand tighten nut. If cotter pin hole doesn’t line up always back off the nut to first alignment hole. This is the method my dad showed me many years ago and after hundreds of bearings over the years no failures (knock on wood!). I think any preload on a trailer bearing is bad as there is no room for heat expansion.
Same way I do it too. :cheers:
 

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Like others I just spin the wheel until it gets noticeable drag on it the I back off 1/8 to a 1/4 a turn until the wheel spins freely again and lock the nut down.

I just did a brake job on my 03 Lightning which requires removing the bearings on the front if you remove the rotors as the bears and races are housed in the rotors. Pretty old school approach on the 2WD 97-04 Heritage F150's, but it works well IMO. Anyways thats the way I always do the brakes on my Lightning. Every brake job it gets new front wheel bearings and they've never failed me. Typically I use Redline grease, but his time I used JD Polyurea grease. Lol
 

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I’ve always tightened the nut with channel lock pliers while rotating the hub assembly with other hand until snug. Stop turning hub, back nut off with pliers then hand tighten nut. If cotter pin hole doesn’t line up always back off the nut to first alignment hole. This is the method my dad showed me many years ago and after hundreds of bearings over the years no failures (knock on wood!). I think any preload on a trailer bearing is bad as there is no room for heat expansion.
Pretty much how I do it. Although I tend to use a socket wrench instead of a Chanel lock pliers.
 

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Pretty much how I do it. Although I tend to use a socket wrench instead of a Chanel lock pliers.
Like MTB98, I've always use the channel lock pliers I used to take the dust cap off with.
 

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A wheel bearing that is too loose will increase tire wear, due to "wobbling". A wheel bearing that is too tight/preloaded will fail due to lack of lubrication. I'd rather replace a $100 dollar tire every 10,000 miles than a bearing and maybe hub and axle every 50 miles!

After replacing bearings, run the trailer for 20-25 miles, preferably with a load, and then stop and carefully tough the hub...it should be slightly warm, but definitely not hot! If too hot to touch, back nut off right then and there. Bob
 

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Like MTB98, I've always use the channel lock pliers I used to take the dust cap off with.
As someone who was in the trailer "bidness" and has seen an axle or three worked upon and more than one missing spindle which started a roadside fire, including one I started myseld north of Denver on the highway and burned 1/2 mile until the rail road tracks to the east stopped the fire, the highway to the west and the exit ramp and overpass road to the north provided a burn line.

The fire from the hot bearings when they came out of the spindle (on a friends trailer that they didn't properly maintain....) spread so fast it was scary, between the strong prairie winds and the vehicles fanning the flames as they passed, the fire spread very quickly.

Using the channel locks that you pull the cap with is also a great way to not over tighten the castle nut. Snug it down till you feel drag on the spinning hub, then back off to the closest point where the cotter pin alignment to re-secure the nut occurs.

Make sure the trailer brakes aren't dragging on the hub when you put it back on so the actual drag you feel is the drag of the bearing being tightened, not the trailer brakes dragging. Some trailers without a lot of use, the brakes maybe frozen somewhat, so make sure the brakes are moving properly before putting the hub back on.

And make sure to use a new cotter pin and then use the channel locks to bend the long arm of the pin over the side of the castle nut, and flare the short arm of the cotter pin around to the castle nut, for the spindle cover to fit back on without contacting the cotter pin. Make sure to tap the center cap so the edges are flush with the axle flange and once they are, you are good to go...............
 
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