Trailer Wheel Bearings - Replacing

[Sammy0884]

Hi Guys,

I want to replace the wheel bearings on my trailer, is this something usually done at home by yourself? or can i pay a mechanic to do it for me?

I do not want to replace them myself and have a failure on the highway.. is it difficult to get done right?

Cheers, Sammy

[Flightmanager]

It is not a difficult job Sam , but it is a bit messy to do properly.

Remove the wheel , and the bearing hub cover.

Remove split pin and casselated nut, retaining washer.

Gently rock hub , and the front bearing will slide out ,

With hub removed , gently pry out rear hub seal, and the rear bearing will come out.

Now , here is where it gets a bit messy. The new bearings have to be filled with grease. Place a small amount of grease in your left hand , and with the bearing in your right , force grease into the bearings by dragging the bearing across the grease. This must be done right the way around the bearing , until the whole bearing is full of grease. I was told many years ago that this is the ONLY way to ensure that all the rollers get covered in grease.

Installation is the reverse of the removal procedure , pack the hub bearing cover with grease to help prevent water entering the bearing enclosure.

Dont overtighten the casselated nut , it should be tight enough to stop any wobble , the wheel should spin true and freely , and with no grinding noises . Should take 20-30 minutes per side .

It might pay you to install a set of bearing buddies while you are at it .

Ross

[Sammy0884]

Cheers Ross, I've pulled the hubs apart when i did the brakes not so long ago, i didn't know if i should be playing with the bearings though... Trailer already had bearing buddies too...I'll give it a go i think...

[a boat]

Cheers Ross, I've pulled the hubs apart when i did the brakes not so long ago, i didn't know if i should be playing with the bearings though... Trailer already had bearing buddies too...I'll give it a go i think...

Hi Sam, you will be able to do it yourself mate, not hard, just messy.

Cheers,

Huey.

[pelican]

You need to be able to determin if the cones ( smooth metal the bearings run on in your wheel hub) are stuffed otherwise just putting in new bearings will just put off an inevitable failure.

Before you pull anything apart with the wheel jacked up spin the wheel - should be silent , spin freely , no grinding and no "notchiness"if there is such a word. Then check your bearing play - sit next to wheel and with both hands wobble wheel side to side , up and down and there should be the slightest of movement but you shouldn't be able to feel significant click click ( going all out with technical talk in this one) when you wobble it.

Next as above that Ross wrote down but also when you remove bearing buddies if there is any sign that the grease is emulsifies with water or if either of the above tests didn't feel right a serious inspection of the cones needs to be done. When removing the old grease rub your fingers through it as you may feel "grit"or metal filings which will indicate something is wrong or worn.

Then it is all pulled apart and you have wiped all the grease out with a rag ( I then just flush with petrol and a rag ( or wipe out with metho) I look really closely at the cones. The cones are the pieces of metal that the bearings run on and are softish metal with a hardened surface that are pressed into the hub. If there is any visible or fingernail feelable ( another technical term) sratches , lips ,, pitting , colour differences , sharp edges they are stuffed. The hard casing on cones once it is damaged ( as it is harder than bearings) will tear the crap out of as many new bearing as you choose to throw at them.

If the cones are stuffed they need to be pressed, cone puller ( or flogged out with a brass drift ) out and new ones pressed in. This is a job that needs to be seen and tried with someone who has done it a bit as there are lots of tricks and they are too hard to write down concisely but take only 10 minutes to show.

The other thing to clean and check when it is all apart it the area behind the wheel where the hub seal rides on the axel. Check it is smooth and clean asthat is the seal most water comes in through.

Grease is much cheaper if you buy a reasonable quantity and bite the bullet now and but a big tin and several tubes so you don't skimp on it. A couple of companies make specific marine wheel bearing grease which is both high temp bearing ( especially with disc brakes and heavy boats) and better water resistant.

My only other warning is to buy quality bearings as they come with better quality seals. Go to a bearing shop and buy SKF ( made in Germany Japan only ones not the china ones) or other known brand as they do last longer due to better tollerences in amnufacture and are more reliable than the shrink wrap at the chain shores. probably cheaper at the bearing store than from the chain store as well.

When dealing with unknown history trailers we have owned we have always done the full monty on them and done bearings and cones as then you know where you stand and as yet we haven't had a failure ( that we didn't deserve - lazyness - whoops). It only takes one near death failure 100k from a town at 2am in pissing rain on a trailer I didn't check ( trusted a mate - his trailer) to ensure you only did it the once.

The best bearing maintainance 30 second check is that when you arrive at the ramp , firsh thing check bearing buddies are still on and have spring loadd up and feel the temperature of the hub. If it is stinking hot ( and teh brakes are cool) you have a bearing issue. Do the same check when at home after returning from the ramp. The build up of temp speeds failure sometimes to the point of molten metal bearings and axels. Keep a spare set or the old bearings in the boot with enough tools as a back up in case you ave a failure.

Ya probably knew this but just in case I thought I write it down as with holidays about to start we will all see the poor bloke on the side of the road fixing his trailer.

I thought we had something on wheel bearing maintainance in teh how to do section but a quick search show nothing?

Edited December 8, 2008 by pelican

[Sammy0884]

Thanks for that Pel.

My bearings are perfect at the moment, no wobble, noises and perfect smooth running... i just want to put a fresh set in as i have no idea how old the existing set are, it will also allow me to re grease the hubs and give it all a good clean... i think i have my next windy day project sorted.

[achjimmy]

My only other warning is to buy quality bearings as they come with better quality seals. Go to a bearing shop and buy SKF ( made in Germany Japan only ones not the china ones) or other known brand as they do last longer due to better tollerences in amnufacture and are more reliable than the shrink wrap at the chain shores. probably cheaper at the bearing store than from the chain store as well.

PEL Last time i went to a bearing store, there bearings were exhorbiant. I found the "timken" brand blister packs at a well known automotive chain store to be good value. Only a few dollars more than the cheap chinese bearings they also sell. And as you may know "timken" were the original manufacturers of cone & cup bearings and generally dont make crap.

Sam where are you located, if in Western Sydney Iam happy to pop around and help you with a side to give you a start.

[chrisg]

When you do them put 3 pairs of the surgical type rubber gloves on.

Remove the old bearings and clean up with one pair, peel off and grease the new ones with the second pair, peel off and do the rebuild with the third pair.

You'll feel daft but it makes life so much easier and you don't contaminate the newies with old crud!

Cheers

C.

[pelican]

Any quality brand of bearing is Fine just aviod the crap ones. Timkin do make high quality bearings but not sure if they are the ones they put in blister packs. I don't really buy many very often so stick with the couple of brands I know. I can't believe the differences in tollerences when mates have put in cheapos - it only takes a few thou and all of a sudden seal is running on a slightly different part of the axel and gets worn fast and quality control doesn't seem consistant.

I use the double glove method a swell and with nitrile ones you an wipe them off with a petrol rag. 3 pairs and my hands are like a cripple as I'm sure they use a small hand as the template - loss of bloodflow in 10 minutes.

Normal gloves get affected by grease and fuel fast and can leave little bits of rubber in the grease if you don't work fast or "melt" on your fingers. The nitrile ones are only a couple of cents cheaper and stop yu getting in contact with oils and grease as they are not porus and don't break down. A lot of the greases and oils have additives in them and are all warning they are cancer causing, skin irritants , poisionous etc. I guess we all should be dead from years of contact but OH& S is a good thing and may as well teach the the young guys the "new " correct thing to do.

Edited December 8, 2008 by pelican

[achjimmy]

Yep the Timken ones in the pack are good quality, USA made if memory serves me. At under $25 a side good value.

[netic]

Sam as stated it is extremely simple........will take you no time at all

[Sammy0884]

Yep the Timken ones in the pack are good quality, USA made if memory serves me. At under $25 a side good value.

or $50 a side for those of us with dual axle trailers.

[stevefish]

apologies for pushing the thread in another direction.

i am concerned about the studs in my hubs, and whether i will be able to get the wheelnuts off too many more times. how do you remove and replace the studs or is it a case of replacing the entire hub?

[WANNAFISH]

Hi Sammy0884,

You can buy those bearing packer but you have 2 use a grease gun. Its a lot less messy and u just have to make sure it goes between the each roller and not just apply it with your hand but manually packing the bearings with grease is the best way to do it. Dont overfill the hub with grease as it still need an expansion space for the grease to circulate. Its better for someone to show you how to tighten the hub as you need the right load or torque for new bearings. Ill be gladly to show you how to do all of this. Ive got a day off on thursday.

Another thing always change the cones thats inside the hub with new ones that came with the new bearings

[achjimmy]

apologies for pushing the thread in another direction.

i am concerned about the studs in my hubs, and whether i will be able to get the wheelnuts off too many more times. how do you remove and replace the studs or is it a case of replacing the entire hub?

Steve you can buy studs. The old ones need to be pressed or knocked out and then the knew studs can by pressed in. Not hard unless the hub is badly rusted.

[dogtooth]

apologies for pushing the thread in another direction.

i am concerned about the studs in my hubs, and whether i will be able to get the wheelnuts off too many more times. how do you remove and replace the studs or is it a case of replacing the entire hub?

Hi Steve ,

Just use a lump hammer and hit the studs inwards . You may as well do the bearings at the same time as the shock hitting your studs wont help your bearings . Do all this with your hubs off Preferably..

Cheers John..

It is not a difficult job Sam , but it is a bit messy to do properly.

Remove the wheel , and the bearing hub cover.

Remove split pin and casselated nut, retaining washer.

Gently rock hub , and the front bearing will slide out ,

With hub removed , gently pry out rear hub seal, and the rear bearing will come out.

Now , here is where it gets a bit messy. The new bearings have to be filled with grease. Place a small amount of grease in your left hand , and with the bearing in your right , force grease into the bearings by dragging the bearing across the grease. This must be done right the way around the bearing , until the whole bearing is full of grease. I was told many years ago that this is the ONLY way to ensure that all the rollers get covered in grease.

Installation is the reverse of the removal procedure , pack the hub bearing cover with grease to help prevent water entering the bearing enclosure.

Dont overtighten the casselated nut , it should be tight enough to stop any wobble , the wheel should spin true and freely , and with no grinding noises . Should take 20-30 minutes per side .

It might pay you to install a set of bearing buddies while you are at it .

Ross

This is spot on well done Ross. So many people never pack there bearings with grease properlly. Only thing i would add is change your bearing cones as there is no point putting new bearings in your old bearing cones . And when your hub is off the trailer degrease with a 2 dollar can of degreaser into a bucket then hose and dry . That way when your Knocking your old bearing cones out you can see what your doing. . Buy a pin punch set to help you out. Slow and steady taps all the way around your bearing cones and watch your thumb....

Cheers John......

Edited December 8, 2008 by dogtooth

[dangles]

just adding the easiest way to get the new cones back into the hub is by using the old one to tap with the hammer. ie sit the new one in as far as possible, then sit the old one on top of this and tap away evenly around. If the old cone is tight in the hub, u can use a drift to tap it back out.

This method saves slipping with pin punches etc and gouging/scratching the new cone

[fisherboy]

The Seal is the item that keeps out the Salt water and should not be overlooked.

With the Bearings, if in doubt replace them. Timken are a great brand (Orange Blister Pack), they also market Boat Trailer seals as well as other companies. These seals have a Stainless steel insert that you knock into the hub after you install the bearing for the seal to run against. Dont wast your time with the one piece seal that run against the rusty axle as they dont keep the water out.

A good rule is to check them by pulling them apart as its easier than on the side of a Highway.

[Blood Knot]

Just a couple of thoughts -

Allways replace the bearing cups (the outer bearing - which is parallel on the outside and tapered inside) when fitting the cones as the interior surface of the cup will be worn and to some extent will not match the taper of a new bearing cone (due to the wear).

It is sometimes difficult to remove the cup(s) from the wheel hub as it is an interference fit in the hub to stop it rotating. More often than not there is not a sufficient amount of the back of the cup ( the thickest part ) showing above its housing to allow it to be easily driven out.

Care should be taken removing the cup and I would suggest using a a mild steel drift to punch them out taking care again, to keep them square to the bore as they are driven out. Ideally they should be pressed out using a plate machined to the correct diameter in a hydraulic press. Pin punches are generally made of steel that has been hardened to some extent and these may cause damage to a hardened bearing do not use pin punches particularly for re-assembly.

John

Edited December 9, 2008 by Blood Knot

[dogtooth]

This is a pin punch and drift punch ... Nearly all are hardened drift and pin . if worried when reassembling you can use large socket when you have tapped the bearing cone in flush just search for the correct size if you have large sockets... Read below for the correct uses for a drift punch and pin punch....

Cheers John...

Pin

pin punch

The purpose served by pin punches is somewhat different from the center punch. A pin punch is used as a driving tool, typically, as the name implies, to drive pins that are used to affix a fixture to a rotating shaft. Pin punches are typically characterized by a hexagonal body, with a long, flat ended cylindrical section.

Drift

drift punch

A drift "punch" is misleadingly named; it is not used as a punch in the traditional sense of the term. A drift punch, or drift pin, is used as an aid in aligning bolt or rivet holes prior to inserting a fastener. A drift punch is constructed as a tapered rod, with the hammer acting on the large end of the taper. The tapered end of a drift punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole. As it is driven in, the taper forces the two components into alignment, allowing for easy insertion of the fastener. Unlike most punches, force is never (and should never be) applied to the tip, or end of a drift pin.

[pelican]

just adding the easiest way to get the new cones back into the hub is by using the old one to tap with the hammer. ie sit the new one in as far as possible, then sit the old one on top of this and tap away evenly around. If the old cone is tight in the hub, u can use a drift to tap it back out.

This method saves slipping with pin punches etc and gouging/scratching the new cone

Hi Dangles

I have used this method before when i have had to but beware you are hitting 2 hardened faces together and depending on how tight it is yu may splinter off a face and get hurt. Yeah I've done heaps but I have seen a couple splinter on bigger bearings and I wouldn't want it in my eye or hand. I have seen the h=fac eon hammers shatter as well.

Only ever use a brass or soft metal drift if flogging out old cones.

Pressing with the correct brass plates is the safest way if you have a press. Sockets are heat treated or hardened so hammer face can splinter and so can cone.

Pel

PS alot people also use a old cone and just gring off the a small part of the outside so it doesn't get stuck when using it as a punch for the new cone - again you are doing a hardened face against a hardened face.

[wonniefisho]

On this same subject (since this thread is fairly recent I'll just ask here) - that I'm assuming from reading all this (and just doing one of mine) that since you tighten the hub bolt, then back it off til the wheel spins without resistance from the bolt itself, that the whole hub and wheel assembly is just being held onto the axle with just the 'loose' bolt and a split pin????? That if for some reason the split pin failed, then one needs to hope the man above us is on our side? In particular since I used a new bolt (replaced the hub as well) it turns a lot more easily than the old slightly rusty one.

Edited December 11, 2008 by wonniefisho

[Dreamtime]

2 pages of confusing advice for something that is a very simple task....

The old cones can be easily removed with a flat blade screwdriver in the 2, 180 degree opposed slots present in nearly every hub.

The new cones are easily driven in using the old cones (make sure the old cones go in the same way as the new cones or there will be no "lip" to knock out the old cones once the new cones are seated).

Soft drifts and splinters and this, that, yarda yarda yarda is "theoretical talk". Its not practical. I have fitted hundreds and hundreds of bearing sets in customers trailers over the years using the above method. Never have I encountered a splinter or any issue. Should you feel the need to wear safety glasses, helmet, radiation suit etc etc then feel free.....

Mate, its a simple job and disregard all the "dire warnings" given here. With regard to replacing bearing cones, of course you would as they typically come as pairs (cone and race).

Hope this helps

[Sammy0884]

Well....

i ended up taking on this task on the weekend just gone, I picked up a blister pack of bearings from my local chain store as it was the only option on a saturday afternoon when i had already pulled two hubs apart.

Disassembly was simple enough save for a few frozen bolts that mount the brake calipers. Then came the biggest headache in the world. Removal of the cones, which ended up being impossible... the drift didn't budge it... a screwdriver did even less... i guess they have been in there since 2002 and simply refuse to come out...they were very very smooth, no lip or scratches.. even the old bearings were perfect... but they were out and on the ground so they were going in the bin, the previous owner probably used the boat a dozen times in its life and lived 1km from the ramp, he also claims to have never submerged the trailer either, so that explains the condition of the bearings.

So, i packed the bearings with grease, and re assembled using the old cones and filled the hubs with grease... i suggest that i will need to get hold of some SKF or NSK quality bearings and get a mechanic to press out the old cones because there is no way in hell i am getting them out.

[BFB]

Sammy0884

I am sorry to hear that you could not get the cones out. Personally I have never had any problems. Sometimes heating the hub helps.

But I would not use any new bearing with old cones. I have learnt over the years, after doing thousands of bearing replacements (My father owned a truck) that you never run a new bearing on an old cone. The cones and bearings are normally made as a matched item and running them the way you have put them together is a recipe for disaster.