PDA

View Full Version : Brake/Tire Temps.



olcoon
08-25-2010, 12:22 AM
I've seen a lot of threads about keeping an eye on the tire air pressure, and putting your hand on the tires to check for excessive heat or using an infa red thermometer to check the temp. I was wondering what temp would be excessive for the tires/brakes? We are heading to Colorado & wondered what temp should I start being concerned for the tires & brakes?

lwmcguir
08-25-2010, 02:02 AM
My simple rule of thumb before I had a laser temp gun was if I cant hold the top of my hand on the tire comfortably then either I am overloaded, under inflated or it is really hot out. Whatever the reason you are running high temp the more likely to see a tire unwind. You all know this by all the tire parts you see on the road. Don't matter what you are driving temperature kills tires and if they are overloaded and under inflated then it happens quickly. Same for the brakes, if you feel around the hub and it is extremely hot you however something going on. Compare with he other wheels and see if one stands out from the others. Best thing to do is have a little safely margin. A lot of folks are upgrading to get that margin in suspension, tires, and wheels.

SouthernNights
08-25-2010, 04:44 AM
I used to use my hand but finally broke down and bought an infared gun last year. With my hand I just looked for any tire that was hotter than the rest. Real scientific but it worked for years.

After a year of checking with the infared what I have found to be 'normal" for our rig is tire temps between 110 and 115. That is on hot days middle of the afternnoon etc. The rear tires on the truck usually are the highest by a few degrees.

jnbhobe
08-25-2010, 05:57 AM
On my TST tire monitor the lowest tire temp setting is 157*. They say no tire is a problem below that. As Larry said my tires run in the 95* to 120* range. My pressures have rose to as high as 127 psi on the trailer from 110 psi. I have no problem with brake temps as I run disc brakes.

jmgratz
08-25-2010, 07:53 AM
I would have to say it all depends on the ambient temperature, speed you are traveling, type of road surface, whether the tire is on the sun side or shady side, type of rubber etc. What I do is check the tires and get a feel for what the average is and if a tire is outside of that then investigate it further. For example: If all of them are 125 degrees and then one is 140 then why is that one 140? Or if the shady side is 112 the sunny side might be 120. I would not recommend using you hand to feel as you might pull you hand back with nasty burns if one is very hot. Also don't forget to check the temperature of the wheel bearings. If one is 'out of normal' or average then it might be beginning to fail. An excellent question.

jayc
08-25-2010, 09:55 AM
I use the "hand on the tire" method too, but after my trip to Colorado recently, I can see the need to upgrade to an infrared thermometer. The tires on the sunny side were considerably hotter than the shady side. It surprised me when it was as hot as it was, but all the tires on that side, both truck and trailer were hot. Maybe Santa will bring me one.

PUG
08-25-2010, 10:30 AM
I agree with what everyone has said above. I saw an add at Harbor Freight last weekend for their $60 infared thermometer on sale for $26 with a coupon. I saw the coupon on their website yesterday again. I have compared the temps displayed to my brothers $100 IT and it is within a degree. The people at Harbor Freight said they have had very little trouble with them. I used mine to check my circuit breakers etc around the house last week. They have a couple different ones but the "gun" style appears to be the best. What the heck $26 bucks>>>

SouthernNights
08-25-2010, 11:25 AM
Here is an interesting (meaning "how dumb can I be?) story that happened on the way back from Nashville last month.

We stopped for fuel just before getting into NC, While the truck was filling up, I grabbed the IT and started checking tires. All good until I got to the last one which was the left steer tire. It read 147 or something higher than all the others. Well Crap-now what. Looked at the tire, felt it with my hand, all good. Double checked the temp. Yup Still 147.

I thought well maybe the plies were starting to seperate. So I drove the next 50 miles or so at 55. Didnt want to change the tire if I didnt have to. Stopped again at the "coffee recycling center" and checked the tires. This time the left steer was back down to normal and the right steer was hot. It finally dawned on me that the IT was picking up engine heat coming out of the wheel well.
As simple as this sounds, I never had that problem with the GMC and it took awhile to figure what was going on.

Lesson learned. pay attention to where you hold the gun and where you shoot the tire.

hillsonwheels
08-25-2010, 09:04 PM
Shoot the "tar"? :( I thought that was only reserved for china bombs! :rolleyes:

Dick

olcoon
08-25-2010, 09:14 PM
Thanks for the info. I had been checking the tires by putting my hand on them. We are now on our first big (Pee Wee's Big Adventure?) to Colorado. Before we left I bought an infra red thermometer because I wanted to keep a close eye on the brake temps while driving in the mountains, plus the tires & bearings. On the way across Kansas everytime we'd stop I'd take the temps to kind of get a feel for the normal temps. BTW from my volunteer fireman days, if you use the back of your hand to check for heat when you feel it the natural muscle reaction to pull away is quicker. We used to do this to doors when in a housefire to see if there was an inferno on the other side of the door. If you do get burnt it will be very minor.

jmgratz
08-25-2010, 09:28 PM
Here is one http://www.grainger.com/Grainger/WESTWARD-Infrared-Thermometer-1VER1?Pid=search

SouthernNights
08-26-2010, 05:31 AM
Shoot the "tar"? :( I thought that was only reserved for china bombs! :rolleyes:

Dick

"Shoot the tar"=a phrase used several ways in parts of the deep south. e.g.1) Them is stealin the chikens-shoot the tars and stop them: or 2) Them is stealing the chikens-shoot the tar out of 'em.


Note: For those of you in the north trying to learn proper english in the south, this is an advanced lesson. Please do not try this at home without supervision.

lwmcguir
08-26-2010, 06:20 AM
I would have to say it all depends on the ambient temperature, speed you are traveling, type of road surface, whether the tire is on the sun side or shady side, type of rubber etc. What I do is check the tires and get a feel for what the average is and if a tire is outside of that then investigate it further. For example: If all of them are 125 degrees and then one is 140 then why is that one 140? Or if the shady side is 112 the sunny side might be 120. I would not recommend using you hand to feel as you might pull you hand back with nasty burns if one is very hot. Also don't forget to check the temperature of the wheel bearings. If one is 'out of normal' or average then it might be beginning to fail. An excellent question.

You use the top of your hand so the reflex is to pull away if it is really hot. And it it is really really hot you will feel and smell the tire. You do want to be careful of course.

Elevatorman
08-26-2010, 06:21 AM
"Shoot the tar"=a phrase used several ways in parts of the deep south. e.g.1) Them is stealin the chikens-shoot the tars and stop them: or 2) Them is stealing the chikens-shoot the tar out of 'em.


Note: For those of you in the north trying to learn proper english in the south, this is an advanced lesson. Please do not try this at home without supervision.


I'll never forget that infamous saying, "I'm gonna beat the tar out of you boy!" ........just as the belt came off!

JohnDar
08-26-2010, 09:21 AM
I picked up one of the Harbor Freight IR guns a couple of weeks ago (on sale). Works great. Haven't had the chance to use it on the trailer tires, but on the truck, the fronts run around 110 and the rear duallys closer to 90. That's after running at 70 mph for about 90 minutes on the freeway. Since it's laser guided, it should only pick up the temp of what the beam is on.

porthole
08-26-2010, 09:50 AM
You use the top of your hand so the reflex is to pull away if it is really hot. And it it is really really hot you will feel and smell the tire. You do want to be careful of course.

The reflex is the same top or palm.
Use the top - so when you do burn your hand it only hurts, but you still can grab and use your fingers without it hurting even more :D




I have no problem with brake temps as I run disc brakes.

What about bearing problems?

Coming back from Nashville we went though Kentucky - Ohio - PA - WV and into Maryland. And we went through some fairly hilly areas. I was using the trailer brakes a bit on one hill, just because I wanted too. I managed to get them hot enough that there was a little bit of smoke coming from the left side (only side I saw in the mirrors).

The good thing though was that they still worked and still work just as good as new. (This was a test and done on purpose)

porthole
08-26-2010, 09:50 AM
I'll never forget that infamous saying, "I'm gonna beat the tar out of you boy!" ........just as the belt came off!


You too?

If the laws of today were around when I was a kid my parents would sill be in jail :cool:

WilmanJim
08-27-2010, 04:58 AM
I even use my IR gun and check the Trucks Oil pan, Radiator Hoses, Turbo and Rear Axle temps at various outside temps, as well as the Trailer tires and Hubs, and record them when we stop at rest areas or fuel stations. Just for references. By the time I get all that done the Turbo is cool enough to shut down.

Jim

porthole
08-27-2010, 09:17 AM
By the time I get all that done the Turbo is cool enough to shut down.



Since you brought that up. I have an aftermarket kit I installed on the truck. Took less then an hour and has a momentary button type switch. Each press of the button adds 1 minute of run time. Pull the key, get out, lock the doors and walk away. It can be set from 1 to 45 minutes. A step on the brake shuts the engine immediately.