Bearings ?

[gloryracing]

Just a question to help my mechanically limited self understand.

Automobiles can travel for 100,000's of miles with no maintenance to wheel bearings. Why is it that trailers need service every year or so with so little mileage? Why can't a trailer have bearings and a setup like an automobile?

[Iwannacamp]

Originally Posted by gloryracing

Just a question to help my mechanically limited self understand.

Automobiles can travel for 100,000's of miles with no maintenance to wheel bearings. Why is it that trailers need service every year or so with so little mileage? Why can't a trailer have bearings and a setup like an automobile?

A few answers... China bearings/seals. Improper installation. Cheap grease(I am sure). Improper service procedures. Non sealed bearings. HEAVY load conditions. Hotter run temperatures.

[2Evil4U]

Bearing style is a big factor as well. The ones used in most late model cars are radial deep groove ball bearings in sealed cartridges. No adjustment possible, just run until they have excessive tolerance and replace.

The bearings on your trailer are 99% going to be tapered roller bearings like old cars used to have. Those would generally be repacked when you have the drum off for a brake job or adjustment.

The added cost to set up a trailer with cartridge bearings rather than just roller bearings on spindles would be spectacular as well. (You'd basically need an independent suspension setup.)

[gloryracing]

My question is 'why' these type bearings/systems are not used on rv/trailer? A new car can be purchased for well under $20k and they have bearings that do not need annual attention.

[510Rick]

One of the reasons is just about every auto parts place sells the basic bearings and seals these trailers call for . The other reason is cost ,sealed bearings are a lot more expensive .

[Iwannacamp]

IMO they are figuring you are going to service the brakes every 5-10K miles and this bearing repack would be a part of that... as it was in the old days. They used to make grease that was not compatible for disk brake applications because the disk brakes ran considerably hotter. Impact resistance/grease shear has a role in the life of the bearings.

[2Evil4U]

Originally Posted by gloryracing

My question is 'why' these type bearings/systems are not used on rv/trailer? A new car can be purchased for well under $20k and they have bearings that do not need annual attention.

Cost and complexity. I don't see in your profile what you tow with, but go look at the front suspension of your TV. Now imagine mounting all of that twice (or 3x) under your trailer.

[gloryracing]

Understand I am not disagreeing with anyone...simply trying to understand. But, if a new car which sells for less than $20k can have lifetime no hassle bearings, why not an rv which sells for 2,3 or 5 times more. I would certainly pay a bit more to never have to worry about and spend maintenance money on trailer bearings. I still just don't yet get it.

[2Evil4U]

Volume and robots.

16,000,000 autos produced in North America in 2016. Vast majority of construction done by robots.

431,000 RVs produced during same time period and that includes non-trailers. Vast majority of work done manually.

No way to amortize the initial investment in an independent suspension on an RV trailer and make it cost effective just so you don't have to maintain your wheel bearings.

[Davidg]

Originally Posted by gloryracing

Understand I am not disagreeing with anyone...simply trying to understand. But, if a new car which sells for less than $20k can have lifetime no hassle bearings, why not an rv which sells for 2,3 or 5 times more. I would certainly pay a bit more to never have to worry about and spend maintenance money on trailer bearings. I still just don't yet get it.

Bottom line? profit. Every part of most rv's are built cheap. The axles, wheels, tires, bearings, frame, and everything else is crap. We keep buying them that way with little complaint. And when you have a problem, there is no one to help. We are at the mercy of the dealer or manufacturer in most cases unless you are very handy. Most repairs are not complicated, but often require a little research. Google/youtube are your friend.

Having said all that, the manufacturers are always in heavy competition with each other to cram more stuff into a trailer and they are always walking that fine line of how much does it all weigh?

I'm fairly good at making repairs, and I've done a number of upgrades to my Silverback, and I've done almost every repair, warranty or otherwise. The manufacturer has shipped me a few parts that I've installed myself.

[Davidg]

Originally Posted by 2Evil4U

Volume and robots.

16,000,000 autos produced in North America in 2016. Vast majority of construction done by robots.

431,000 RVs produced during same time period and that includes non-trailers. Vast majority of work done manually.

No way to amortize the initial investment in an independent suspension on an RV trailer and make it cost effective just so you don't have to maintain your wheel bearings.

Yep, that pretty well covers it. I suspect the same is true for items installed on or in an rv, such as applicances, cabinets, etc...

[gloryracing]

Originally Posted by 2Evil4U

Volume and robots.

16,000,000 autos produced in North America in 2016. Vast majority of construction done by robots.

431,000 RVs produced during same time period and that includes non-trailers. Vast majority of work done manually.

No way to amortize the initial investment in an independent suspension on an RV trailer and make it cost effective just so you don't have to maintain your wheel bearings.

Thanx for the replies.

I understand the economies of scale and see how it would be a bit more expensive for rv manufacturers. Still, motorcycle/atv/side by side manufacturers produce in small numbers and yet include independent suspension, lifetime bearings, disc brakes, etc at retail prices much less than rv's.

So is this accurate....a different type/style bearing is needed and this bearing only works with independent suspension which would cost more than rv buyers are willing to pay? Wonder what that mass produced cost would actually be???

Is part of it perhaps that we as rv buyers put up with the industries bs and lack of providing what is needed?

[m35a2]

You could always buy a motor home. 400k but you wouldn't have to worry about bearings.

Seriously though, most people these days don't keep vehicles long enough to worry about wheel bearing replacement. They do go bad though and replacements aren't cheap.

[FFred]

"Bottom line? profit. Every part of most rv's are built cheap. The axles, wheels, tires, bearings, frame, and everything else is crap. We keep buying them that way with little complaint."

The bottom line is purchasers that ONLY look at their initial cost,

so the competition is for LOW initial cost buyers.

There are fantastic inverters (Mastervolt) that cost $2,000 to $4,000 but most folks will accept a $129 cheapo , and simply replace it when it fails.

Many fresh water pumps are under $100, they fail in full time use ,
but the better units Galley Maid are close to a grand.

Some Mfg have axle upgrades you can purchase on a new TT, a wise investment for long term travel.

A mfg that did "high end" TT would find few customers ,
as the will is seldom there to pay for it.

[NMWildcat]

Originally Posted by gloryracing

Is part of it perhaps that we as rv buyers put up with the industries bs and lack of providing what is needed?

Ok, let's start a class action lawsuit for our current rigs, and refuse to purchase any more new RVs. You go first

[gloryracing]

Based on some of the industry crap that I have read about I would not be surprised if a lawsuit does come about. This is Murica! How bout a fresh water tank falling out of a trailer and causing harm to someone. Certainly is well documented that this is a 'flaw' but continues to be manufactured simply to save money.

[Blackrock]

A properly grease packed wheel bearing that has the nut turned down to the proper spec should run for 50K miles before needing service. That said, many premature axle failure can be attributed to improper initial setup. I am a retired mechanic and worked my last 22 years for the Az Dept of Transportation and we serviced wheel bearings on every type of unit imaginable. Our fleet manager found that a lot of the younger techs had no idea how to properly set the preload on a bearing and how to judge the difference between a grease pack and an oil bath type

[Davidg]

Originally Posted by Blackrock

A properly grease packed wheel bearing that has the nut turned down to the proper spec should run for 50K miles before needing service. That said, many premature axle failure can be attributed to improper initial setup. I am a retired mechanic and worked my last 22 years for the Az Dept of Transportation and we serviced wheel bearings on every type of unit imaginable. Our fleet manager found that a lot of the younger techs had no idea how to properly set the preload on a bearing and how to judge the difference between a grease pack and an oil bath type

I agree with you. Would you mind telling us how you perform a wheel bearing setup? I have always done it this way; after packing wheel bearings and installing all parts except the dust cover I tighten the castle nut to aprox 50 ft/lbs while turning the wheel several rounds. Then stop turning the wheel and back off the nut until it is free, then lightly hand tighten, then install the cotter pin or nut locking clip. Then before installing dust cover, I will spin the wheel and check axial clearance just to make sure there is not excessive play. I used to establish a barely perceptible amount of axial "play"...probably .003-.005, just guessing.

So, am I missing anything?

[325BH]

Camper/RV manufacturers cheap-out for sure. There is however nothing wrong with Timken bearings. They are used in many things, including the axles of our trucks.

The "sealed for life" bearings used in cars have their own limitations. You start getting heavy and an inner/outer Timken setup is pretty bullet-proof.

[Blackrock]

Originally Posted by Davidg

I agree with you. Would you mind telling us how you perform a wheel bearing setup? I have always done it this way; after packing wheel bearings and installing all parts except the dust cover I tighten the castle nut to aprox 50 ft/lbs while turning the wheel several rounds. Then stop turning the wheel and back off the nut until it is free, then lightly hand tighten, then install the cotter pin or nut locking clip. Then before installing dust cover, I will spin the wheel and check axial clearance just to make sure there is not excessive play. I used to establish a barely perceptible amount of axial "play"...probably .003-.005, just guessing.

So, am I missing anything?

No, you are doing it right. For the final setting I always err to the tight side if the castle nut winds up in the middle. Some folks like the Red Tacky type of grease but I use the good black nasty Moly grease. But about any good quality EP-2 will work.