35” towing PSI

As the title says, I’m trying to figure out a good PSI to put my 35” tires-10 ply E load rating for when I tow my camper that’s about 4500lbs. Just looking for opinions, did research but it seemed all over or not for 35” tires.

 

Chalk test your rear tires. Then hook up camper and load gear, chalk test again. Add psi and chalk test until the same footprint is shown.

 

Camper or travel trailer? Big difference as 1 is loaded and 1 is towed. Towing with E-rated , just go as is. I have SL tires with a 5000LBS Surf Boat and don't touch them, be quite honest I haver never ever ever changed my pressure to tow anything.

 

It’s a travel trailer, I’m running 32 psi now but was worried they would heat up too much at that temp going through the Smokey mountains

 

You should be around 45-50psi to get the same load rating on E tires as you would on the stock SL tires at 35psi

 

I’d do 53 rear and 47 front.

 

Every answer online, with no mention of what tires and what weight will be on the rear, is at best a guess (maybe an educated one, but a guess).

First thing to do is figure out the weight that’s going to be on the rear tires. You can do calculations or just go weight the setup on a scale somewhere. Gets a little tricky to get the right weight, but it’s doable.

Ex: drive the truck and trailer onto a scale and drive the front axle of the truck off the end of the scale, leaving the rear axle and trailer axle(s) on the scale. Get a weight. This is the combined weight of the trailer and the weight on the rear axle. Next, drive forward until the trucks rear axle is off the scale and only the weight on the trailer axle is on the scale. This is the weight carried by the trailer axle. Subtract the two and you’ll have the weight the trucks rear axle carries.

….you could also just take the factory numbers for the weight on the rear axle of the truck, add any gear in the truck bed and add the tongue weight of the trailer and get pretty close.

THEN, go to the manufacturer who makes the tires you have. Look for information on their website (or contact them directly to ask) what weight ratings the tires have at certain PSI.

Find the relation between the weight the rear axle carries and what PSI safely gives you a conservative ability to carry that amount of weight, with two tires carrying that total load.

That’s now your minimum PSI, going above that would be determined by personal preference, handling characteristics of your specific setup or desire for different tire wear needs or MPGs.

Sounds like too much effort and you just want someone to give you a “good enough” PSI? Well…it’s really not that much work and it’s the right thing to do in order to be a competent and safe operator of the setup…so please just spend 30 minutes doing it….or as others have said, default to going to MAX PSI (as specified on the sidewall of your tire).

 

Tandem axle trailer with an E-rated tire towing 5000 lbs...I wouldn't change shit. Hook and go. I am 60 and have been towing 40 years and not once did I add air for ANYTHING. I am sure the nervous Nellies would, me....PFFFTTT hook and go

 

Funniest thing I have read in years. I sent it to some people who haul for a living.....Thank you from all of us

 

Why is it funny to you?

 

Since you’re towing a trailer that weighs about 4500lbs, then that would put somewhere around 500lbs of tongue weight on the back of your truck. To put it in perspective, that’s the same weight as 2~2.5 american males. That’s all the input that i got for you.

 

That light of weight - you’re probably fine as low as 40. 45-50 would make me feel better.

 

Regarding knowing the numbers and chalk testing, both strong advice! Def ask your manufacturer for a similar chart as below.

This is from Falken for my 33" LR-E:

"Most OE’s use a factor of safety of about 1.5 meaning the tire can support 1.5x the vehicle load to account for dynamic loads (braking, cornering, whoops off-road, etc.) The Tundra OE P275/55R20 can handle the max GVWR but without a ton of safety margin, so my recommended pressures are going to be a bit higher than OE."



Rear 1 is actual truck weight, unloaded. Rear 2 is my axle weight with trailer. Ignore Rear 3.

As a result, I run 40 all around unloaded, and bump it up to 50 front, 55 rear when towing. Chalk tests confirm a good contact patch.

 

I always see people posting this question. Real answer is what is on tire is the recommended pressure. If tire is not performing well with that heavy of a load. Then you haven't got right tire for job. If you are overloading your tires ability it is still going to squat. Because that tire is not recommended for that load.

Answer is what is on sidewall. Maximum pressure would be for heavy load. If you are not loading tire heavy little less pressure for comfort. Not lot less because it would cause tire to wear funny. Don't forget to rotate also.

 

chalk test is ideal but this tool will put you just about where you need to be. Ive used it for years and follow up with chalk test to confirm and it is always within a pound or two of ideal.

 

The tire only lists the maximum pressure rating of the tire. So it’s not a default, nor often relevant, pressure to set your tires, it’s just the max.

If you set your tires at the max PSI and aren’t hauling at the limits of the tires weight rating, you’re going to get horrible center tread wear and be more susceptible to tire damage.

 

Are you paying for the dental bills for everyone that inflates to 80psi?

 

Would nitrogen help at 80psi?

 

Maybe helium.

 

I didn't offer too. What I said adjust accordingly to load pressure. If you are not hauling and you are running LT's. I would run them around 60-65 psi. Any lower and they will wear funny. LT tire is not necessary to support a 4500 lb camper. P metrics could do that towing.

 

Too answer your question. I would run them about 65 or 70 to tow that camper. That shouldn't feel squirmy at that pressure.

 

We can agree on that.

 

That is a relief, I was hoping for your agreement.

 

Remember celebrity death match on MTV,?

 

Yeah I remember it. Remember when MTV started. They had little popup messages during songs?


https://www.youtube.com/watch?v=6jcdwiV6dXw

 

Messages, not so much. Song details, at beginning and end, yes. But good find on the OG broadcast.

 

VH1 was the pop-up video.

 

https://youtu.be/8s-rBa8BL30?feature=shared