Dexter bearing adjustment procedure

[Timeking]

I totally get NOT using the EZlube fitting (ruined some brakes), Timken parts, and annual service. What I don't get is the conflicting methods being used to set the zero backlash on the bearing, i.e., 0.001 to 0.005 clearance.

My previous trailer had Alko axles, and I adjusted the bearing per Alko recommendations: rotate and tighten to 20 ft-lbs, loosen nut without motion, tighten to 8 ft lbs, back off one castellation, stick the pin in. Never had a problem in 60,000 miles.

My 2018 Rockwood has Dexter axles. Dexter says to rotate and tighten to 50 ft-lbs, loosen the nut, and then "hand tighten" the nut and back off a bit. What kind of procedure is that? Hand tighten?

If you go on Youtube, people are doing all sorts of crazy stuff, everything from tighten by hand and back off a full quarter rotation.

The Alko method seems scientific, the Dexter method seems weird, and many of the Youtube ideas will cause a failure I'm sure.

So .... from someone who has actually done this several times, and has gone 10's of thousands of miles ... how are you doing it?

PS: Dexter didn't see fit to install brake adjustment hole dust plugs which causes me concern for their commitment to quality.

[Ron3rd]

fj12ryder wrote:

Ron3rd wrote:

Timeking wrote:
That gives me a bit of assurance. When I first had a TT back in 2007, I paid a mechanic to repack my bearings ... and everyone of them failed. Spent hours and hours pounding all the races out and re-seating. Don't ever want to go through that again.

They all failed because he was a know-it-all expert mechanic in his mind and set the bearings too tight and did not follow the Dexter procedure. A tight bearing will burn up quickly; a slightly loose bearing will not.

Yes a tight bearing will bind and heat up and go south...but you have no idea what that "mechanic" did. You weren't there, and you're simply speculating, but you sound a lot like "a know-it-all expert mechanic in his mind". You might want to put an "I imagine" in there somewhere.

Hmmmm... every bearing failed after "the mechanic" repacked them. "I imagine" he did not follow the proper procedure which anyone can do if one can read at a 5th grade level. But some mechanics are smarter than the Dexter engineers. BTW it's clear he set the bearings too tight since all 4 failed. But I wasn't there, maybe he did everything right and all 4 failed by coincidence . Or he forgot to add grease.

[Timeking]

OK, so I called Dexter 575/295-7888 xferd to Warranty and talked to a tech. I told him I have 10F 4000lb axels, that I tighten to 50 ft-lbs with a torque wrench while rotating, loosen nut, tighten by hand, put on the clip, and the clip and bolt have some play.

HE TOLD ME THIS IS THE CORRECT METHOD TO USE FOR THIS
AXEL!!!!!!!!!!!!!!!!!!

Over and out.

[Timeking]

Muddying this up much? How much pressure do you think is on the bearings when you do a tight turn on the Walmart parking lot, and either the rear or the forward tires have to slide sideways? Alot!!

I wasn't comfortable with 50 ft-lbs, but a little late on that idea (if indeed correct).

[fj12ryder]

drsteve wrote:

RJsfishin wrote:
Tapered roller bearings and self adjusting brakes have not changed in in nearly 50 years,.so why all the hype ?

Think what you must, but torqueing a wheel to even 30 lbs, much worse turning it under that much torque, is asking for brg failure.
Turning a wheel under any more than finger tight, removes any and all grease that was applied to the rollers and race in that wheel. The clearance (play) in a bearing it to leave space for grease, not for expansion. But Dexter is God, so do it !

You're right. I'm sure the engineers who design these things know nothing about how to service them.

But a lot of times the engineers are overruled by the lawyers and BS artists who have to make sure all their bases are covered. The engineers say "That's too much" and the lawyers say "Better too much than not enough, it covers our butts".

OTOH I also think 50 lbft. is way too much.

[drsteve]

RJsfishin wrote:
Tapered roller bearings and self adjusting brakes have not changed in in nearly 50 years,.so why all the hype ?

Think what you must, but torqueing a wheel to even 30 lbs, much worse turning it under that much torque, is asking for brg failure.
Turning a wheel under any more than finger tight, removes any and all grease that was applied to the rollers and race in that wheel. The clearance (play) in a bearing it to leave space for grease, not for expansion. But Dexter is God, so do it !

You're right. I'm sure the engineers who design these things know nothing about how to service them.

[RJsfishin]

Anyone who blames bearing failure on the Chinese MFG, needs to be educated,....seriously !

[Timeking]

Thanks Lynmor. There is play in all the nuts under the clip, not much, but some. So I guess I did it OK.

I've serviced various bearings on TT and boat for 20 some years, just never ran into the 50 ft-lb and the hand tighten bit and the clip retainer, thus the source of my worry.

Its not just that your tire falls off. Its when your tire falls off coming down the west side of Monarch Pass in CO. Never happened to me, and I don't want it to ever happen. Ever.

[Lynnmor]

That 50 ft. lb. specification really just pertains to newly installed bearings and races so that they are fully seated. The instructions are written to insure that it was indeed done and was not neglected by a previous installation. It takes almost no torque to squeeze out excessive grease before final adjustment. If you are torquing to 50, be sure the wheel is spinning while tightening the nut. Also, be sure that the wheel does not move as you loosen and then do the final adjustment, so that grease isn't rolled back in. While there is a variety of retaining methods for the nut, all you are trying to do is get the least amount of play, but still have some.

I have had bearing failures and all were the result of defect Chinese manufacturing or water intrusion. The water intrusion was on snowmobile trailers where the axles are bathed in salt brine plus being operated in extremely cold temperatures.

[Timeking]

OK, I am just trying to make sure I did this correctly WITH THE CLIPS NOT WITH CASTLENUT AND COTTER PIN.

https://www.dexteraxle.com/resources/videos/bearing-maintenance

I used a torque wrench not a 12 inch wrench as shown in video because I have damaged shoulders (need leverage to get to 50 ft-lbs, I can't put 50 lbs of force on a 12 inch wrench).

[fj12ryder]

Timeking wrote:
... I think that Dexter's procedure is shooting for something close to a pre-load like used on semi trailers (google it). The wheel turned freely, so I guess I did it right.

...

You definitely don't want any preload. If you preload those bearings they will soon fail. How semis do it is immaterial to how your wheel bearings should be. Any preload is too much preload.

[fj12ryder]

Lynnmor wrote:

fj12ryder wrote:
Yes a tight bearing will bind and heat up and go south...but you have no idea what that "mechanic" did. You weren't there, and you're simply speculating, but you sound a lot like "a know-it-all expert mechanic in his mind". You might want to put an "I imagine" in there somewhere.

You haven't serviced your brakes in 8 years, so you may have no idea what is going on in your brakes and bearings.

I serviced them the year before last year, so it had only been 6 years. And they were fine as were all the bearings.

[RJsfishin]

Tapered roller bearings and self adjusting brakes have not changed in in nearly 50 years,.so why all the hype ?

Think what you must, but torqueing a wheel to even 30 lbs, much worse turning it under that much torque, is asking for brg failure.
Turning a wheel under any more than finger tight, removes any and all grease that was applied to the rollers and race in that wheel. The clearance (play) in a bearing it to leave space for grease, not for expansion. But Dexter is God, so do it !

[Timeking]

Sorry. I got confused about where its been. It is a 2018 trailer. Purchased new Aug 2017. So OH back to FL, run away to AL and MS from Irma, then run away from Florence and David to NC, TN etc. So ~4000 miles.

PS: 2016 to 2018 is "8 years"? We have had it 1 year and 4 months.

[Lynnmor]

fj12ryder wrote:
Yes a tight bearing will bind and heat up and go south...but you have no idea what that "mechanic" did. You weren't there, and you're simply speculating, but you sound a lot like "a know-it-all expert mechanic in his mind". You might want to put an "I imagine" in there somewhere.

You haven't serviced your brakes in 8 years, so you may have no idea what is going on in your brakes and bearings.