Towing and tire pressure

[johnboytoo]

I'd still suggest you go by a cat scale to get your weights and see if the tires are up to the task

[nachtmsk]

Just got back from my trip. I put the tires at 45psi each. What a difference that made in towing. I hardly knew I was pulling anything. I was really surprised at the difference.
I'll put them back down to 35 when I'm not towing.
Thanks for all of the advice!
Mike

[johnboytoo]

That's great....

I ran to get the 5er to load up for next week's trip and since the storage area is only 10 miles, didn't really think I needed to bump up the pressure --- WRONG - felt like I was driving on marshmellows

[mike06081969]

Good news, Mike! Glad that it towed better at the increased pressure.

[r2millers]

Originally Posted by Kingfish58

The sticker in my 2012 Crewmax with 275/65 18's specify 30psi on the front and 33 in the back.

You need to find the type of tire you have and determine whether that tire should even be used for towing?

I'd be very careful of any tire for towing that suggests a 30 psi inflation.
I would Never tow with P (passenger) rated tires although there are HD tires for light towing. If you are seriously towing, ensure you have LT (light truck) tires.

Mine inflate to 90lbs max.
My trailer tires are E rated, 80 psi max.

[nachtmsk]

r2millers -
Thanks for the concern and advice. The tires don't suggest they be set at 30 psi. That is just what they are put at when I go in for service. Probably because that's what it says on the door sticker. But the tires aren't the stock tires that usually come with the truck.
The sidewall says that max cold pressure is 50psi.
The truck came with a tow package installed. Not sure if that means they would automatically put a 'towing' tire on the rig. Probably not.
I will look at the sidewall and see if I can figure out more info about the tires. I've already put a call into the dealer but haven't heard back yet. I'll be trying that again.
Mike

[johnboytoo]

if the dealer changed tires, that changes the ratings... and the mfg would probably have something to say about that ---- good luck !

[nachtmsk]

I checked the Mich site.
It has this next to the tire: 305/50R20/XL 120 H
Does anyone know how to decipher this? What does the H mean? Is that the rating?
It also says: Max Load Single: 2806@50

http://www.michelinman.com/tire-sele...ck-to-top-link

[mark5w]

Below is a list of speed ratings along with the corresponding speeds they represent. Remember, the speeds are test speeds, not recommended speeds.

• B - Up to 31 mph
• C - Up to 37 mph
• D - Up to 40 mph
• E - Up to 43 mph
• F - Up to 50 mph
• G - Up to 56 mph
• J - Up to 62 mph
• K - Up to 68 mph

• L - Up to 75 mph
• M - Up to 81 mph
• N - Up to 87 mph
• P - Up to 94 mph
• Q - Up to 100 mph
• R - Up to 106 mph
• S - Up to 112 mph

• T - Up to 118 mph
• U - Up to 124 mph
• H - Up to 130 mph
• V - Up to 149 mph
• W - Up to 168 mph
• Y - Up to 186 mph
• Z - 149 mph and over

[Lloyd]

Mark, I don't understand what that is suppose to mean????

[avvidclif]

It means his tires are rated for up to 130 MPH.

They can carry 2806 lbs@50 PSI. Now look and see how that compares to the sticker. If the tires are rated higher then you should be OK, if lower????

[mark5w]

From Tire RAck:

Speed Rating
In Germany some highways do not have speed limits and high speed driving is permitted. Speed ratings were established to match the speed capability of tires with the top speed capability of the vehicles to which they are applied. Speed ratings are established in kilometers per hour and subsequently converted to miles per hour (which explains why speed ratings appear established at "unusual" mile per hour increments). Despite the tire manufacturer's ability to manufacturer tires capable of high speeds, none of them recommend the use of their products in excess of legal speed limits. The maximum operating speed of a vehicle must be limited to the lowest speed rated tire on the vehicle.
Speed ratings are based on laboratory tests where the tire is pressed against a large diameter metal drum to reflect its appropriate load, and run at ever increasing speeds (in 6.2 mph steps in 10 minute increments) until the tire's required speed has been met.
It is important to note that speed ratings only apply to tires that have not been damaged, altered, under-inflated or overloaded. Additionally, most tire manufacturers maintain that a tire that has been cut or punctured no longer retains the tire manufacturer's original speed rating, even after being repaired because the tire manufacturer can't control the quality of the repair.
Over the years, tire speed rating symbols have been marked on tires in any of three ways shown in the following examples:
225/50SR16225/50SR16 89Sor 225/50R16 89S
Each of these was an acceptable method of identifying speed ratings.
Early tires had their speed rating symbol shown "within" the tire size, such as 225/50SR16. Tires using this type of branding were not to have been produced after 1991.
225/50SR16112 mph, 180 km/h225/50HR16130, 210 km/h225/50VR16in excess of 130 mph, 210 km/h
Beginning in 1991, the speed symbol denoting a fixed maximum speed capability of new tires must be shown only in the speed rating portion of the tire's service description, such as 225/50R16 89S.

[Lloyd]

Thanks. I think that was more then I wanted/needed to know.

[Tim D]

My Mud Claws say M+S. What does that mean?

[mike06081969]

Originally Posted by Tim D

My Mud Claws say M+S. What does that mean?

Mud and Snow

[mike06081969]

As for load carrying capability, that is usually expressed as "Load Range" on a radial tire. For example, I have Load Range E tires, which correspond to the old 10 ply tires. A lot of people still call Load Range E tires "10-ply".

[Tim D]

Originally Posted by mike06081969

Mud and Snow

Hah. That was a stupid question! I was looking for a speed rating.

[mike06081969]

Originally Posted by Tim D

Hah. That was a stupid question! I was looking for a speed rating.

No such thing as a stupid question. (Although most of the ones I ask would appear to be so, lol.)

[Tim D]

Originally Posted by mike06081969

No such thing as a stupid question. (Although most of the ones I ask would appear to be so, lol.)

You are too kind. I felt like a dumb@$$ after I realized what I done. Oh well, If you can't laugh at yourself you can't really laugh at anyone else.

PS. They are rated Q. 100 mph. lol

[nachtmsk]

I wasn't looking for how fast I could go, I was looking for how much I could tow.
There should have been a course in college -- Tires 101, because with all the letters and various scales/charts, I still have no idea if my tires can carry the load I'm putting on them. It seems a simple question and an important one, but no where on the tire does it say (Can tow up to xxxx lbs). It says each tire can carry 2806lbs on the Mich web site, so does that mean I need to multiply by 4 to get the full load they can carry or multiple by 2 (Back tires only). Does that number refer to tongue weight or full weight of trailer?
At least I know I can go 130 mph, though not the most useful piece of information. I've gone through a summer towing my 6000lb TT and it's been fine. So I will likely leave it at that. But I will try one more time to call the dealer and see what they say.
I wonder if Michelin has an 800 number. That would be handy!
Thanks for all the input everyone.
Mike