Proper Wheel Bearing pre-load?

[steve.barnett71]

What is the proper way to set wheel bearing pre-load? With the tire on I can get about 1/8" of movement when I check mine. I think this is about right but wanted some more expert opinions.

Thanks.

[bfs673]

There are many videos on you tube on this topic. I only suggest that as it's not specific to any axle brand / size.
But simply, while spinning the wheel, hand tighten the castle nut by hand until tight. I often spin the wheel/hub and tighten the castle nut with a pair if channel locks until the wheel experiences some friction while turning.
I then loosen the castle nut and tighten again by hand. I always loosen and tighten slightly by hand while spinning to ensure there is no increased friction while spinning the hub.
Once I have the tire on, I always try to rock the tire back and forth from the top/bottom and left/right sides to ensure there is no play.

It's hard to explain via text, but some videos will definitely help!

[steve.barnett71]

There are many videos on you tube on this topic. I only suggest that as it's not specific to any axle brand / size.
But simply, while spinning the wheel, hand tighten the castle nut by hand until tight. I often spin the wheel/hub and tighten the castle nut with a pair if channel locks until the wheel experiences some friction while turning.
I then loosen the castle nut and tighten again by hand. I always loosen and tighten slightly by hand while spinning to ensure there is no increased friction while spinning the hub.
Once I have the tire on, I always try to rock the tire back and forth from the top/bottom and left/right sides to ensure there is no play.

It's hard to explain via text, but some videos will definitely help!

Thank you.

The process you described is the basic process I used when I installed the bearings. After a couple short trips I was checking everything out. I have a slight amount of play, no more than 1/8" max. Several sources I have researched like Etrailer suggest some small amount of play.

Just want to make sure I won't have a bearing problem on our trip to Yellowstone.

[LV Naturist]

Thank you.

The process you described is the basic process I used when I installed the bearings. After a couple short trips I was checking everything out. I have a slight amount of play, no more than 1/8" max. Several sources I have researched like Etrailer suggest some small amount of play.

Just want to make sure I won't have a bearing problem on our trip to Yellowstone.

The proper way to set the preload on trailers, assuming you are reusing the bearings and races (not replacing the races), is to torque the castle nut to 20 ft-lbs while spinning the wheel. Then back off until the nut is loose (maybe 1/2 to 3/4 turn). Then hand tighten until slightly snug. At this point, adjust the nut to the loose side just until the locking device can be installed, whether it is a cotter pin or a holding snap. When done properly, you should feel SLIGHT movement. Again it's hard to describe a feeling in text, but you should be at just the point where you feel movement. If there is more than that, the bearings are too loose. If you're feeling 1/8" movement, they are too loose (I realize that was just a guesstimate on your part). If you were to set up a dial indicator, you would want +/- .005" end play.

If you have replaced the bearing races (always replace bearings and races as a set) then the initial torque should be 50 ft-lbs to make sure the races are properly seated in the hub, back off till loose, then torque to 20 ft-lbs and adjust as above.

John

[jkwilson]

The proper way to set the preload on trailers, assuming you are reusing the bearings and races (not replacing the races), is to torque the castle nut to 20 ft-lbs while spinning the wheel. Then back off until the nut is loose (maybe 1/2 to 3/4 turn). Then hand tighten until slightly snug. At this point, adjust the nut to the loose side just until the locking device can be installed, whether it is a cotter pin or a holding snap. When done properly, you should feel SLIGHT movement. Again it's hard to describe a feeling in text, but you should be at just the point where you feel movement. If there is more than that, the bearings are too loose. If you're feeling 1/8" movement, they are too loose (I realize that was just a guesstimate on your part). If you were to set up a dial indicator, you would want +/- .005" end play.

If you have replaced the bearing races (always replace bearings and races as a set) then the initial torque should be 50 ft-lbs to make sure the races are properly seated in the hub, back off till loose, then torque to 20 ft-lbs and adjust as above.

John

X2! Couldn’t have better described how I do it. (Honestly probably couldn’t have done it as well )

[steve.barnett71]

The proper way to set the preload on trailers, assuming you are reusing the bearings and races (not replacing the races), is to torque the castle nut to 20 ft-lbs while spinning the wheel. Then back off until the nut is loose (maybe 1/2 to 3/4 turn). Then hand tighten until slightly snug. At this point, adjust the nut to the loose side just until the locking device can be installed, whether it is a cotter pin or a holding snap. When done properly, you should feel SLIGHT movement. Again it's hard to describe a feeling in text, but you should be at just the point where you feel movement. If there is more than that, the bearings are too loose. If you're feeling 1/8" movement, they are too loose (I realize that was just a guesstimate on your part). If you were to set up a dial indicator, you would want +/- .005" end play.

If you have replaced the bearing races (always replace bearings and races as a set) then the initial torque should be 50 ft-lbs to make sure the races are properly seated in the hub, back off till loose, then torque to 20 ft-lbs and adjust as above.

John

Thanks John,
I used the method your describe to adjust all the bearings. I can just barely feel movement but cannot see or measure it. I feel much better about our upcoming trip.

[LV Naturist]

Thanks John,
I used the method your describe to adjust all the bearings. I can just barely feel movement but cannot see or measure it. I feel much better about our upcoming trip.

You're welcome! My emphasis in the quote is exactly what you're supposed to feel. Good job and have a safe trip.

John

[huntindog]

There are many videos on you tube on this topic. I only suggest that as it's not specific to any axle brand / size.
But simply, while spinning the wheel, hand tighten the castle nut by hand until tight. I often spin the wheel/hub and tighten the castle nut with a pair if channel locks until the wheel experiences some friction while turning.
I then loosen the castle nut and tighten again by hand. I always loosen and tighten slightly by hand while spinning to ensure there is no increased friction while spinning the hub.
Once I have the tire on, I always try to rock the tire back and forth from the top/bottom and left/right sides to ensure there is no play.

It's hard to explain via text, but some videos will definitely help!

I wil add that I hate the term "preload" as when it is done right, there id NO preload. Bearings are supposed to run at zero clearance. For that to happen they NEED a slight amount of play when cold... If there is no play when cold, they will be to tight when the assembly heats up and expands in use.

I hate to tell someone I do not know how to do it by feel. Too easy to get it wrong.
Instead I tell them to READ the manual for your specific axles to get the proper procedure. Follow it precisely and you will end up with the right amount of play.

[LV Naturist]

I wil add that I hate the term "preload" as when it is done right, there id NO preload. Bearings are supposed to run at zero clearance. For that to happen they NEED a slight amount of play when cold... If there is no play when cold, they will be to tight when the assembly heats up and expands in use.

I hate to tell someone I do not know how to do it by feel. Too easy to get it wrong.
Instead I tell them to READ the manual for your specific axles to get the proper procedure. Follow it precisely and you will end up with the right amount of play.

WOW! Thought I was seeing double for a moment there^^^

Anyway, I understand what your saying, and "Preload" does seem to be a misnomer but it is technically correct. It's not like a pinion bearing or side bearings in a differential where you preload the bearings and leave it there. However, even though the final outcome has no "preload" it is important to preload the bearing initially to make sure everything is seated properly and to give a reference/starting point if you will for the final adjustment.

John

[huntindog]

WOW! Thought I was seeing double for a moment there^^^

Anyway, I understand what your saying, and "Preload" does seem to be a misnomer but it is technically correct. It's not like a pinion bearing or side bearings in a differential where you preload the bearings and leave it there. However, even though the final outcome has no "preload" it is important to preload the bearing initially to make sure everything is seated properly and to give a reference/starting point if you will for the final adjustment.

John

I understand that,,,,I also know why one has to leave the bearing preload in most differentials ( I have set them up a number of times)
But from what I read on forums, that term gets a lot of shade tree trailer mechanics in trouble.