Towing Wander.....

[EdZacko]

Make sure that your tire pressure for each axle matches the weight carried for each axle (including the trailer) - very easy to overlook. I recommend weighing and recording the weight of each axle for the load you are carrying if you haven't done so already.

I have heard people refer to what @Ozymandias mentions as "tire squirm" which can occur with new tires. I personally have never experienced this situation, but I am certainly not saying that it doesn't exist.

In 2015, on a return trip from visiting the east coast, I stopped in El Paso, Texas and replaced all four Michelin LTX tires with another set of the same. I asked that the front tires be aired to 55 psi and the rear tires to be aired to 50 psi. (I was pulling a travel trailer with gross combined weight of 12,500 lbs - rear axle weight was 4000 lbs).

I left El Paso and for the next two hours of driving I felt exactly the symptoms that you mentioned. Each time I passed a semi, or one passed me, I felt a subtle continuation of sway that was never there before. Tire squirm? I was thinking maybe so. Then I started thinking a bit more about it - Discount Tire (whom I've used for years) has a habit of airing up rear tires to 80 psi. So, I stopped at the next rest area and discovered that this was the case. I reset both rear tires to 50 psi and left the rest area. Trailer sway gone! The rig handled exactly as it did before the new tires.

If it were my rig, the first two things I would check would be axle weights and tire pressure.

- John

I had this happen years ago with a Suburban. It got so bad that it was dangerous to drive---You AIMED IT! When a semi would pass--especially when going down hill the squirm would start and I would have to ACCELERATE to stop it---really scary. I had the front suspension and steering gear checked and no one could ever find anything wrong. Then one day I took the truck for state inspection and had to leave it outside the gate. I was standing in the bay when the tech drove the truck up to enter the bay and was astounded to see the front tires wobbling like crazy---it was comical----what had happened was that the inner plies of the tires had shifted internally---this had evidently been going on for some time and had now become critical. It was only when looking at the truck coming at you that it was noticeable. Turned out that all four tires were doing the same thing. Vhanged the tires and the truck ran straight and true.

Just a thought.
Eddie

 

[Too Tall]

Person opinion but I would stay with 65/80 psi or you will sway worse and reduce the load limit of the tire. I have the same tires and brake in is not a factor for me. (Very good tires). For me, to reduce sway, I reduce tongue weigh by spreading the load to the front of the truck by raising the rear. However this does shift more weight to the rear of the camper so having the proper tongue weight and trailer loading is necessary to achieve this.

 

[AH64ID]

Person opinion but I would stay with 65/80 psi or you will sway worse and reduce the load limit of the tire. I have the same tires and brake in is not a factor for me.

You can carry that opinion, but tire manufacturers don’t agree.

Proper pressure for the load is always the recommended pressure for street use, towing or empty. There are minimum pressures to adhere too, but generally those don’t apply when towing.

 

[Too Tall]

I just go by RAM's recommendation which is 65/80, they don't specify street vs towing.

 

[Cummins12V98]

I just go by RAM's recommendation which is 65/80, they don't specify street vs towing.

most likely that is for max axle rating.
Know your weights and use the weight/inflation chart you your tires.

I add 10psi fronts snd 5 psi rears. 65k on my DRW tires.

 

[AH64ID]

I just go by RAM's recommendation which is 65/80, they don't specify street vs towing.

Ram’s recommendation, just like what’s stamped on the wall, is based max load and not actual load. Ram uses the axle weight rating, the sidewall uses the load index of the tire.

 

[Too Tall]

Understand load charts vs tire pressure but I'm lazy and with 65/80, I don't have to worry about the mule, I just load the wagon, ha.

 

[Cummins12V98]

Understand load charts vs tire pressure but I'm lazy and with 65/80, I don't have to worry about the mule, I just load the wagon, ha.

Understand load charts vs tire pressure but I'm lazy and with 65/80, I don't have to worry about the mule, I just load the wagon, ha.

FACT, running 80 rear unless loaded to your RAWR you will have a poor ride, less stopping and poor tire wear.

 

[AH64ID]

FACT, running 80 rear unless loaded to your RAWR you will have a poor ride, less stopping and poor tire wear.

Additionally, the tires are more susceptible to road hazards and punctured.

Many more reasons to worry about the mule when you’re overinflated vs proper inflation. People are just too lazy these days.

 

[Topzide]

The Laufenns that I put on my truck like 65psi in the front to run without wearing them but in the rear, 55psi works and the ride is so much nicer! The DW has noticed the difference in the ride as I've settled in on the pressure changes. That's why they make portable air compressors that fill these tires fast without breaking the bank! I keep a load chart on my phone and know close enough on what load is to keep them where they need to be. Safety is first followed by comfort. Even the factory tires can be made to ride nicer and last a bit longer if pressures were adjusted as needed.

 

[slowmover]

CAT Scale is the start point as in my earlier post. RAM pressure range respected inside of Load & Pressure Table.

There’s a minimum for the load. The maximum isn’t that far above it. Work with real numbers using scaled axle values.

Guesstimates don’t cut it. I average well over 100k per tire set as a result of not being too lazy to get true numbers and do a minimum of testing to verify.

Chalk lines, etc, aren’t valid.

Too much air pressure is the common RV’er sin. Increases risk. Handling & Steering are not tire pressure problems, per se. Address the chassis as is proper after W/D hitch settings (if applicable).

.

 

[AH64ID]

The Laufenns that I put on my truck like 65psi in the front to run without wearing them but in the rear, 55psi works and the ride is so much nicer! The DW has noticed the difference in the ride as I've settled in on the pressure changes. That's why they make portable air compressors that fill these tires fast without breaking the bank! I keep a load chart on my phone and know close enough on what load is to keep them where they need to be. Safety is first followed by comfort. Even the factory tires can be made to ride nicer and last a bit longer if pressures were adjusted as needed.

Even then 55 psi is good for over an 8K RAW, have you tried lower when empty?

 

[Cummins12V98]

"I average well over 100k per tire set as a result of not being too lazy to get true numbers and do a minimum of testing to verify."

Sounds like me, I would get WELL over 100k running 3rd get take offs on my 98 12V.

65k on my DRW Michelin's towing 24k 5er 1/2 the miles with a 6k pin.

 

[Topzide]

@AH64ID, At 55 psi, they've got a nice profile on the pavement and ride is great. Going lower might cause some weird wear issues. Think I'll just stay with 55 psi and go up if needed pending load.

 

[AH64ID]

@AH64ID, At 55 psi, they've got a nice profile on the pavement and ride is great. Going lower might cause some weird wear issues. Think I'll just stay with 55 psi and go up if needed pending load.

If you’re empty I doubt you get any weird wear issues on stock sized tires. The rim width is perfect for the stock size, and should wear perfect at 35 psi, unless the load dictates more. They should actually wear better at 35 than 55, if the load is appropriate.

I’ve never seen funny wear issues from running chart pressure, even on the front where some folks swear that you have to run overinflated for proper wear.