Trailer axle seals short life

[t700]

Thanks for the end play spec.
We will use a laser thermometer to monitor temperature
Do you run Lucas hub oil or synthetic 75-90 and what temps do they run?

Thanks for the help
T700

[Chamberpains]

Problem with switching to grease is you'll probably never know if the seal failed or grease is low or dry until it burns up because of very easily overlooked grease leak.

Just in case someone doesn't have Stemco's official torque procedure here is a DIRECT DOWLOAD LINK
https://www.google.com/url?sa=t&source=w...vv4P8QJofc

I also believe the final 1/4 back off is too much. Rawze goes with a straight 50 ft/lbs preload. I personally found that a hair tight and lost a bit of fuel mileage. So I back mine off 1/8th which comes out to .001-.002 movement. I also take A LOT of extra wheel turns while doing the initial 200 ft/lb torque more than a couple times to insure everything is seated. Beaings, races and seal. Then proceed to back off, then torque to 50 ft/lbs then back off my final 1/8th.

[Hammerhead]

(07-31-2018 )t700 Wrote:  Thanks
The Stemco procedure calls for torque to 200 spin repeat 2 more times
Back off
Torque to 100 spin repeat 2 more times
Final step back off 1/4 turn

Not sure what the final torque is

Will try your method with the final torque at 50

Thanks
T700

Whoa whoa whoa whoa!!!!!
Are you talking the Stemco Pro-Torq bearing nuts?

IF YOU ARE, YOU MAY NOT BE FOLLOWING THE DIRECTIONS PROPERLY!!!
Please read Step 4 B in This instruction sheet again VERY CAREFULLY!
There is ONLY ONE TRAILER AXLE NUT THAT GETS BACKED OFF 1/4 TURN!!!
ALL THE REST ONLY GET BACKED OFF 1/8 TURN!

I’m thinking you’re axle nuts are too loose.
Verify the endplay with a dial indicator, this is the PROPER way to confirm you’ve done it correctly.
These bearing nuts are so repeatable it’s ridiculous. Following the instructions properly results in 0.001-0.002” every damn time. And I STILL verify it with a dial indicator.
I’m not kidding, I get well over 200,000miles running between 20-23,000lbs per axle!
No Problem.
I change seals after 3 years or so to change the hub oil, and I rarely have one fail in between time.
IIRC, I’ve changed 2 unscheduled trailer wheel seals in the last 10 yrs, and I have 6 trailer axles.

[t700]

Thanks Hammerhead for your reply.
We have the Stemco Pro-Torq bearing nuts.
The nut we have is the 447-4743 which is the only one with the 1/4 final back off.

On the next seal will try 1/8 final back off, check end play with gauge, and monitor
temperature on the road.

T700

[Hammerhead]

(08-02-2018 )t700 Wrote:  Thanks Hammerhead for your reply.
We have the Stemco Pro-Torq bearing nuts.
The nut we have is the 447-4743 which is the only one with the 1/4 final back off.

On the next seal will try 1/8 final back off, check end play with gauge, and monitor
temperature on the road.

T700

If your trailer uses 447-4743 bearing nut, then I stand corrected on the 1/4 turn back-off.
I wonder what kind of trailer axles you have, I have never known anyone to require the 4743 nut.

DO NOT BLINDLY FOLLOW THE ADVISE OF SOME JACK@$$ on the interwebs! If you have THAT nut, then follow the procedure as described. But make sure you use a dial indicator to verify endplay, this setting is very critical. Wheel bearings and such are NOT parts and procedures to "just wing it", wheel-offs are NOT something anyone should experience.

The amount of "back-off" is determined by the TPI (Threads Per Inch) of the spindle. The finer the threads, the more turn it takes to accomplish the correct amount of relief, so please follow the procedure.

What bearings does this axle use?

[t700]

Thanks for the advice.
This is a 2007 Utility Reefer that was built from the factory for super singles and can not run duals. Tire wear has been good and we have a spare super single on rim on a tire rack under the trailer in case of problems.
Most trailers who run super singles have been converted from duals.

The original bearings appear to be Chinese.
We have replaced 2 sets with: Timken set#413 HM212011 and HM212049
set# 414 HM218210 and HM218248
These are taper bearings
National seal 370025A or Stemco Voyager Seal
373-0143
May try the SKF seal if we continue to have problems

T700

[Hammerhead]

(08-03-2018 )t700 Wrote:  Thanks for the advice.
This is a 2007 Utility Reefer that was built from the factory for super singles and can not run duals. Tire wear has been good and we have a spare super single on rim on a tire rack under the trailer in case of problems.
Most trailers who run super singles have been converted from duals.

The original bearings appear to be Chinese.
We have replaced 2 sets with: Timken set#413 HM212011 and HM212049
set# 414 HM218210 and HM218248
These are taper bearings
National seal 370025A or Stemco Voyager Seal
373-0143
May try the SKF seal if we continue to have problems

T700

Ok, thanks for the info.
I run the SKF one piece Scottseals, in green boxes.

[gatow900]

(07-31-2018 )t700 Wrote:  We have a 53' 2007 Utility reefer.
The trailer has super singles, which we like.
A new axle seal will only last about 6 or 7 month, so with the 4 axles we are replacing all the time.
The axles have the Stemco single nut system and when we replace a seal the Stemco procedure is followed.
Were using Lucas hub oil, but for the last 2 seals switched to synthetic 75-90 which have not leaked yet, but has been only a couple of months.

One guy we know packed bearings with grease and changed end caps and according to him has not had any problems.
I have heard that changing to grease can be hard on the spindles.

Suggestions would be greatly appreciated.

T700

Don’t use the Lucas it clogs the breath hoe in the cap. It builds pressure and u get a leaky wheel seal

[Redland1]

I don’t know if big trailers have the same seals as goosenecks,but I will tell you that if the proper procedure is not followed seals will fail prematurely.Also everything in the assembly needs to be super clean because any debris will shorten the lifespan of the seal as well.Synthethic oil boils at a much higher temp than regular oil and usually extends the life of the seal.