Tire Question

[Teri C.]

I think Toxic pointed out something I didn't think about. If a tire reads Maxium Load 2033 lbs? What exactly does that mean? If your boat and trailer weigh 2500lbs, does that mean those tires can't tow my boat because it's too heavy? The car is rated at 5000lbs and 500 tongue weight so I know it's capable. Would I have to buy new tires or what?

 

[Bruce Freeman]

2033 lbs max per tire.. So 2 tires = 4066 lbs. 2033 x4 8132

so I would not worry about your tires..

BF

 

[Mike Levesque]

Teri, I'm not positive, and I'm sure someone here will have a definitive answer for you, but my guess would be that load rating is for each individual tire? And that you're just fine with them. Remember, the only added weight load (I think) from the trailer is a couple hundred pounds at the hitch, and all that other weight wears more on the engine, brakes, transmission, etc...... like I said, that's just a guess tho...egMike

 

[Mike Newman]

Just another note. Tire ratings are listed at the specified tire pressures. As pressure drops then the load rating also drops. Also as the tire pressure drops the side walls flex more which creates excessive heat at highway speeds and starts to breakdown the rubber compounds. End result is early tire failure normally by blow-out.



... Always keep an eye on the tire pressure.

 

[Staci Matheis]

Teri -



From an ex-Goodyear Commercial Fleet Sales Manager, don't worry! You are in great shape! The tires are more than sufficient to do anything you'll ever put them through.



Just be sure to keep them inflated - I always keep mine at the maximum pressure on the sidewall of 35#. It's kind of hard to explain, but it is actually the air inside the tire that carries the load - the tire is just the container.



me!



(Big title only means I sold truck tires to fleets.)

 

[TOMMY RICH]

If there bias-ply like the standard trailers for the aluminum rigs then most should be run at 50 PSI...I found out after I started gettin' wear on the outside edges. I'm runnin' them @50PSI now and it's going away.

TEE

 

[Staci Matheis]

TEE -



She's talking about the tires on her new QX4 which should be "B" load range and maximum inflation of 35#.



me!

 

[Larry Harp]

I'll say for sure that the tire pressure makes a big differance in how the boat/trailer pulls. I was noticing the trailer was bucking and bouncing and I was thinking about how when I first bought the boat it pulled so easy I would almost forget it was back there. I checked the tire pressure and both tires were down to 35. Aired 'em back to 50#'s and all is great again. I'll be checking every trip now.

Harpo

 

[Teri C.]

I just noticed that me! (Scott/Staci, not sure what you prefer, just let me know) said to inflate the tires on my Infiniti to 35. That's what my TrailBlazer was but these tire say to inflate to 44PSI Maximum. The dealer has all 4 at 32. What do you think?



By the way, it's really nice to have you guys around. I feel like I can ask questions without feeling stupid or getting yelled at. Thank you!

 

[Greg Meyer]

Hey Terri... That Commercial Fleet Tire guy will get you your answer 'bout them tires...



The other matter.... Now when "I" want to feel stupid I just put my hand on my face... worls every time...LOL



Just keep asking questions... shows you are smart enough to want to know the right answers... That's what I like about this place... the wealth of information is astonishing

 

[Bruce Freeman]

There are as many answeres to tire questions as there are tires. The car/truck maker will recomend a tire pressure for the ride. The tire maker will offer a pressure for max tire wear and saftey.. I am from the old school where you do what the tire says I run 50 in my 6ply pick up tires and 32 in my car tires. In your case if the tire say 44 lbs I would pick a round number like 40 and set the tires there. See if the ride becomes to rough for you.. I would think not with that quality of SUV and keep an eye on your tire wear. Wears out the center too much air, wears out the inside and outside not enough air. If you have them checked every time you get your oil changed you should never have a tire related failure..Other than stuff in the road of course. Unlike "ME" who basicly said the same thing in 300 less words I still sell tires.

BF

 

[Staci Matheis]

Teri -



First, I really do prefer Staci.....



Now, on to how much air.....





Your tires are "containers" for the air. The maximum inflation pressure listed on the sidewall should be considered the "capacity" of the container. Like a 1 gallon jug or a 55 gallon barrel. You can fill the container all the way to the top or leave it half full / half empty!



Remember, the air is what carries the load. You need 44# of air to carry 2033# of load at each corner. If you have less of a load, you can get by with less inflation pressure.



Automobile manufacturers will often show (or at least used to) inflation pressures for front and rear tires based on the front and rear weights of the vehicle. When possible, carrying less air than the maximum can sometimes cushion the ride for passengers..... But if the pressure is too low, it can also lead to heat build-up in the tire and eventually to delamination of the plies and blow-outs.



This was a big part of the Firestone/Ford Explorer fiasco. Ford was recommending lower pressures in the tires so that their buyers would not feel a "truck-like" ride. The tires were not well constructed to begin with and the additional flexing and heat build-up resulted in tragedy.



Why were your tires at 32#? My guess would be that whoever prepped your car didn't know any better than I did - that your tires were rated for 44#.



Do you need to have 44# in the tires at all times? Probably not..... BUT..... If it were my vehicle, I would carry that much or close to it. The ride might be a bit harsher, but you will benefit from increased load capacity, better and longer tire wear and better overall handling and control response. Not to mention safety!



Well..... That's kinda the story in a nutshell.....



me!

 

[Scott Hammer TOXIC]

No one has addressed the "low profile" aspect of the tires. Does that make a difference. I would think that the low profile would require maximum inflation due to the fact that there is less sidewall to absorb bumps and dips. Is there a risk of her banging a rim? Slicing a tire? Bruce? Staci?



TOXIC

 

[Staci Matheis]

Under "normal" conditions? Not really. I wouldn't begin to be concerned as long as the tires are properly inflated.



Low profile tires were developed for increased handling performance. There is less sidewall to flex so the steering response is much quicker and more accurate.

 

[Teri C.]

Holy crap Batman!! Tires are complicated. I just thought the SUV looked really nice (I know typically female). Guess I didn't think about all the details. I need to get all this straightened out before I drive 14 hours to Minnesota. At this point, I am thinking of putting 40 in all 4 tires. My trailer tires are rated at 50 and I have 50 in each. Any objections let me know. Thanks for the explanation, Staci.

 

[Staci Matheis]

Gets the "Thumbs Up" from me!

 

[Scott Hammer TOXIC]

Teri,



Low profile are the tires with less sidewall. Look at the tires on my explorer then look at yours. You will notice that if you measure from the rim to the edge of your tire I have a LOT more tire between the rim and the ground. Like Staci said, less sidewall more stability in handling but I was concerned about the tires ability to "absorb" a bump, pothole, whatever, under increased load. I think tongue weight is all you have to worry about added to any loading you do to the vehicle. Your trailer tires take the boat weight.



TOXIC

 

[Michael Frank]

It really depends on the weight that you are putting on the tires. If you have a tire rated at 2033 lbs per tire, on a estimated 4000lb vehicle, then max inflation is probably going to be a little overkill. I would definately not recommend running at max PSI in the front, you will affect the handling and steering of the vehicle. (i.e. wandering, twitchy steering, etc.)



Although it's a bit of a pain, you could always do the chalk test. Take a big piece of white chalk (kids sidewalk chalk works well) and make a thick line across the tread face of the tire, outside to inside. Drive 30 or 40 feet and check the line. If it's all evenly rubbed off, you're good. If the outside edges of the line are gone, but the center is still there, you are under inflated. If the opposite is true, you are over inflated.



That is method Jeepers use to judge proper inflation when going to larger-than-stock tires. My Jeep has 33x12.5x15 tires on 15x10 rims, and I run 26lbs in each to keep the tread flat on the road. My tires are load range C, 2550lbs at 50 psi, but my 3,800lb Jeep doesn't need anywhere near that much load capacity, and really gets squirrely at higher psi.



When towing with my Expedition, I run the fronts at 33psi and the rears at 38psi, factory says 32 and 35. The handling gets really bad if I go up any more in the front. If you are running factory stock size tires, you are usually fine running whatever it says on the door jamb sticker or your owners manual for the front tires, and maybe add a couple of psi in the rear when towing. Like egMike said, the boat probably only adds about 200-300lbs (usually 10% of gross trailer weight) on rear of the vehicle, everthing else is carried by the trailer. Your engine, tranny, and brakes are going to be abused more than the tires.



Sorry to blather on, I'm bored at work, and this topic comes up once a week on the Jeep boards.

 

[Larry Harp]

I'm impressed! Where else except the good old NTOWS could you get this much information about tire pressure?

Harpo

 

[Bruce Freeman]

And just think we have not even gotten into the aspect ratio yet.

BF

 

[Scott Hammer TOXIC]

or offset rims.....



TOXIC

 

[Staci Matheis]

I use Comet to clean my white lettering!





SOS pads work well, too!

Just harder on the fingers!