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trailer brgs. and digitial temp readings? waht should they be?
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trailer brgs. and digitial temp readings? waht should they be?
bought a digitial temp gauge with infra-red pointer and checked the bearings on a dual axle trailer, with disc brakes on one axle...about 5300 lbs, boat and trailer.
ambient outside temp about 60 +. front axles read about 65-75 degrees F, rear read 95-105 degrees.
anybody have any idea what temp. the bearings should be after warmed up?
Re: trailer brgs. and digitial temp readings? waht should they be?
Speaking from EXTENSIVE experience with my new trailer with malfunction (dragging) disk brakes all the time. Hot is 185 to 205 degrees. Be very careful if things get that hot. When they are working correctly In the summer in Florida hubs run 120 to 135. Winter they run about 110. My boat goes around 6,000lbs when loaded...You are fine!!!
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RE: trailer brgs. and digitial temp readings? waht should they be?
Quote:
Capt. John Deering - 11/29/2006 6:11 PM
anybody have any idea what temp. the bearings should be after warmed up?
An axle without brakes will be about ten degrees above ambient temperature after several miles of trailering. I now have disk brakes on both axles and the hubs are about 140 degrees after several miles of city (stop and go) traffic. It depends on how much braking you are doing and how heavy your trailer is (how much weight you are stopping).
The important thing is that the temperatures are nearly equal on each end of a particular axle. Anything else indicates a problem.
RE: trailer brgs. and digitial temp readings? waht should they be?
While some of the temperature difference can be a result of the brakes, with a tandem axle trailer it can also indicate tongue height problems. The 30 degree difference in your hubs may be a result of the tongue being too high and placing more load on the rear axle than the front. Change the drawbar and bring the tongue down about 3 inches and see what change it makes in the temperature.
I've found that hubs should not run much over about 35 degrees above ambient. The brakes do play into it, but unless you're towing in the Rockies, they should not be a major factor - if they are not dragging. Tow the trailer on a flat and level stretch for about 10 miles. Make a gradual stop, going uphill if possible and check the temps quickly after you come to a stop.
RE: trailer brgs. and digitial temp readings? waht should they be?
Quote:
kerno - 11/30/2006 2:08 AM
While some of the temperature difference can be a result of the brakes, with a tandem axle trailer it can also indicate tongue height problems. The 30 degree difference in your hubs may be a result of the tongue being too high and placing more load on the rear axle than the front. Change the drawbar and bring the tongue down about 3 inches and see what change it makes in the temperature.
I've found that hubs should not run much over about 35 degrees above ambient. The brakes do play into it, but unless you're towing in the Rockies, they should not be a major factor - if they are not dragging. Tow the trailer on a flat and level stretch for about 10 miles. Make a gradual stop, going uphill if possible and check the temps quickly after you come to a stop.
I believe the difference in thempratures is because he only has brakes on one axle.
As a person who has operated the same trailer with drum brakes on one axle, then disk brakes on one axle, and finally, disk brakes on both axles, I can state from personal experience that disk brakes run hotter than drum brakes (there's less mass to disperse the heat) and that hubs on axles with brakes will run considerably hotter than hubs on non-braking axles. The way brakes work is to convert motion (energy) into heat. Use your IR thermometer to measure the actual rotors and you'll be surprised - they will be over 200 degrees if you've been doing much braking. Check the tow vehicle - same thing.
You make a valid point about towing a tandem axle trailer as level as possible. Not only for braking, but to avoid overloading one of the axles or the tires. Hook the trailer to the tow vehicle and park on a level surface. Measure from each end to the pavement or put a level on the frame. If it's not level, get the appropriate ball mount to make it level.
RE: trailer brgs. and digitial temp readings? waht should they be?
Our hubs run 105 to 108 with the tires 125 to 135. The sunny side tires are usually 3-5 degrees warmer. Front and rear axles are usually within a degree or two of each other. Ambient temperatures 80+.
I need to shoot the asphalt next time, see how that relates.
Re: trailer brgs. and digitial temp readings? waht should they be?
I shoot mine with a temp gauge also. They run between 110-130 degrees. Ambient temperature will change your readings a little bit.
I'd start to worry if you got over 150 or any one hub shows a big difference. I have SS Disc brakes on all four wheels and there is no difference front to rear or left to right.
RE: trailer brgs. and digitial temp readings? waht should they be?
Quote:
rwidman - 11/29/2006 8:06 PM
The important thing is that the temperatures are nearly equal on each end of a particular axle. Anything else indicates a problem.
From my experience, that may not always be true. Last August I was trailering on I-75 going south in the afternoon and when I hand checked the hubs at a fuel stop, the right side was much hotter than the left. I got worried. My son offered that it could be the sun causing the difference, since that was the sunny side of the rig. That night I checked the hubs again and they were much cooler, and about the same temperature. I think he was right.
Re: trailer brgs. and digitial temp readings? waht should they be?
Capt. John, it sounds like your brakes are mounted on the rear axle if the rear is warmer than the front. It is my understanding that if you only have brakes on one axle of a tandem axle trailer, they should be mounted on the front axle. Am I misreading something?
By the way, I just bought an IR thermometer and will start taking readings soon also as I am curious.
Re: trailer brgs. and digitial temp readings? waht should they be?
Quote:
Bokat - 11/30/2006 10:38 PM
Capt. John, it sounds like your brakes are mounted on the rear axle if the rear is warmer than the front. It is my understanding that if you only have brakes on one axle of a tandem axle trailer, they should be mounted on the front axle. .
Champion Trailer says they should be mounted on the rear axle:
Quote:
When only one brake axle is being installed on a tandem axle trailer, the brakes should be on the rear axle for maximum system performance. Rotational torque applied to axles during braking shifts the equalizer and applies more weight to rear axle. If brakes are installed on the front axle, the wheel may skid during braking. Brakes on rear axle are more effective as the equalizers shifts and the rear tires dig in to the pavement.
Actually, this only applies to certain spring configurations and not to tandem axle trailers.
Many states require brakes on all axles if brakes are required at all. As someone who has towed with and without "all axle brakes", I highly recommend adding brakes to the remaining axles.
Re: trailer brgs. and digitial temp readings? waht should they be?
rwidman,
It would be nice if the "experts" could get their stories straight, wouldn't it? I have a tandem axle Boat Master trailer with brakes on one axle. They said the brakes should be on the front axle as did one other manufacturer I talked to. Who knows?
It seems logical to me to have the brakes on the front if they are only on one axle. The front brakes on a car or truck are more effective than the rear. Can we apply that same logic to a boat trailer, I would think so, but then again, who knows?
RE: trailer brgs. and digitial temp readings? waht should they be?
my brakes are on the front axle...its a nextrail out of florida, i think when you purchase a trl. buy oversize. its a 7000 lb. trl. on scales boat tr. etc. are about 5300 lbs. trl. weighs about 1000 its a dual aluminum bunk set-up. probably should have bought a 10, 000 lb. trl. bearing temp today 110 degees on the braking axle. fun post!
Re: trailer brgs. and digitial temp readings? waht should they be?
Quote:
Bokat - 12/1/2006 10:30 PM
rwidman,
It would be nice if the "experts" could get their stories straight, wouldn't it? I have a tandem axle Boat Master trailer with brakes on one axle. They said the brakes should be on the front axle as did one other manufacturer I talked to. Who knows?
It seems logical to me to have the brakes on the front if they are only on one axle. The front brakes on a car or truck are more effective than the rear. Can we apply that same logic to a boat trailer, I would think so, but then again, who knows?
It would be nice. Their explanation has something to do with the way the equalizer acts during braking. I don't believe it applies to torison axles (there is no equalier) and it may not apply to all spring configurations.
As I said above, you are better off with brakes on both axles of the trailer just like on a car. I could really tell the difference when I added brakes to the second axle. You are doubling the braking power and the road contact of this braking power.
Re: trailer brgs. and digitial temp readings? waht should they be?
rwidman,
You are right about the brakes on both axles. One of these days I'll get to that project. I have torsion axles, so that may be the difference. I just switched from the bronze brakes that came with my Boat Master to the Kodiak brakes. So far I think they are a better brake. We could probably pose this question to Steve @ East Coast Trailers.
Re: trailer brgs. and digitial temp readings? waht should they be?
Bokat,
I have heard arguments on both sides regarding the placement of a single axle brakes on a tandem or tri-axle trailer.
I would think the forward axle would do a better job stopping the trailer (just as you said) and have less chance of locking up or skidding. I have also read what rwidman posted regarding rotational torque and equalizers and this could very well be valid.
I had a galvanized tandem axle leaf spring suspension Shorelander trailer (say that fast five times) that I purchased new about 15 years ago. It had a single axle of drum brakes and they were on the front axle. I was told by the dealer the brakes were on the front axle because there was less chance they would be dunked in saltwater and would last longer (LOL). I really don't recall seeing a single set of brakes on the rear axle of a tandem or tri-alxe trailer here in FL.
Sorry I don't have any scientific data to provide and I'm sure there will always be varying opinions on this subject. I have always seen them on the front axle.
trailer brgs. and digitial temp readings? waht should they be? 
