New trailer tires for trip

[RVEagle]

We're planning a 6,000 mile trip and decided to replace the 4 year old "D" rated tires with new Goodyear Endurance "E" rated tires. Didn't have problems with the old, just wanted new and better. Last week I picked the trailer up from the tire shop and brought it home - pulled nice but only a 10 mile trip. Got home and noticed that the valve stems were not the HP stems they told me they were going to install - I had 65 psi stems on 80 psi tires. I talked to the salesman and he says bring it back and they will make it right. Today I bring it back to them, again pulls nice. I leave the truck and trailer and go get something to eat. Come back an hour later and we're good to go. I bring it home and it doesn't pull so nice. It may be me, but it seemed like there was some wiggle back there that I don't remember from before. So here's the question .... is there something that they could have done (or not done) that changes the stiffness of the tires while replacing the valve stems? My two thoughts were low air pressure or lug nuts not tight. I checked the air - all at 80 psi. Any other possibilities? And yes, it may just have been me being too sensitive, I just don't want to start a 6,000 mile trip with a wiggly back end (sway?) that wasn't there before.

[BarabooBob]

Did you check to see if they connected your WDH properly? My guess is that they didn't get it set up the same why you had it.

[dalford]

I assume you checked the lug nut torque? Also, check your axles and your leaf springs and hangers.

To change the valve stems they needed to Jack the trailer to remove the wheels. Did they jack it correctly? Anyway, worth an inspection.

[RVEagle]

"Did you check to see if they connected your WDH properly?" - The Trailer was never unhitched from the truck.

"I assume you checked the lug nut torque? Also, check your axles and your leaf springs and hangers." - I put a 100 ft-lb torque wrench on the lug nuts and nothing moved. Visual inspection of the axle did not reveal anything "unusual" but I'm not sure I would know what I'm looking at/for.

Thanks for your suggestions.

[CGK]

X2 dalford - if they didn't jack-up the RV properly, there could be damage to the WDH and/or other components. The fact that it was still hitched to the TV when they jacked it up may make it MORE likely they damaged something. Happened to our best friends last year. That said, it isn't a sure bet there is damage - just something you'll want to check. If nothing is bent, broken, loose (but not previously loose), etc. you might check the set-up to see if anything changed. Good luck!

[JimMorrell]

Just the difference with 80 psi in those tires is going to make a bunch of difference in the way it handles.

[Brother Les]

You have a bearing going out....


6,000 miles.......

[rlocicero]

was there any wind?

[jadatis]

Was the pressure first time also 80 psi, or did they put it on 65 psi then.

If you give me tire and TT specifications, I can calculate a safe pressure for you.

From TT , best weighed axle loads, or GVWR GAWRs number of axles.

From tires: sises or maxload .
We know AT 80 psi now and AT 65 psi before.

To much psi can also give a wigly ride.
If the D-load really needed 65 psi, the E- load needs about 70 psi for the same weight.

Also give the maximum speed you use, and wont go over for even a minute.

[Iwannacamp]

Got my E's in yesterday....

[RVEagle]

CGK - " if they didn't jack-up the RV properly, there could be damage to the WDH and/or other components." - I've unhitched the trailer and all seemed fine.

JimMorrell - "Just the difference with 80 psi in those tires is going to make a bunch of difference in the way it handles." - They were at 80 psi both times. I would think 80 psi would make them stiffer than 50 psi.

Brother Les - "You have a bearing going out.... " - I had the bearings inspected when the tires were replaced, they said they were fine (trusting the quality of the inspection, when they can't put the right size valve stems on I know is questionable)

rlocicero - "was there any wind?" - No, not really.

jadatis - "To much psi can also give a wigly ride." - The tires are ST225/75R15. The max trailer weight is 9000 lbs on 4 tires, 2250/tire. The tires need 55 psi to meet that load, while at 80 psi they can handle 2830 lbs each. I've got a lot of margin, which I was looking for. I'm not expecting max inflated tires to flex more when under less load. Wrong expectation?

Again, thanks for the comments and suggestions - keep them coming!

[jadatis]

For 9000 lbs traierweight, so minus 10% on pin is 8100lbs , I came to 75 psi, as max reserve wih no screws trembling lose, and no nervous roadhandling, but that 5 psi more must not be a problem.

Hoped to show you, it could be lower safely, but no. Hoped it was that simple explanation , but no.

What pressure did you keep in the old tires?
Still possible it has to do with the pressures.

My system is to lower ST tires in maxload by 6 loadindexsteps is about 15% , to give it the lesser deflection a LT tire of further same specifications would have .
Toghether with adding 11.1 to assumed axleload, then filled in in my extra safe formula, gives that reserve with good handling and livetime of 6 years or more.

But some LT tires have a history of given maxload, other then official calculation would give, and then my system for ST can be disturbed.

This means for your situation, that it is still possible that 75 psi is over my border of " comfort" , and your wigling still is because of to stiff tires so not enaugh deflection.

From your reaction I make you misunderstand and think more deflection by higher pressure, but correct me if wrong.

[Native Texan]

I am looking to do the same upgrade with a very similar trailer that I just pulled around 1000 miles on the original C rated tires to get it home. Mine pulled great as it was, although it did need some tightening on the sway control bar after the first few miles. Sure they didn’t ‘adjust’ your sway control bar, depending on what type of hitch you have, to maneuver the trailer at the shop?

The E rated tires would be much stiffer.

[cajunmansion]

I just replaced my tires with the Goodyear endurance with max 80PSI the TT weight is 7600 pounds unloaded. I’m getting the same thing.

[RVEagle]

jadatis - "What pressure did you keep in the old tires? " "From your reaction I make you misunderstand and think more deflection by higher pressure, but correct me if wrong." - The old tires were Load C rated and I kept them at 50 psi. My understanding is that the higher the pressure the stiffer the tire, the less the deflection.

Native Texan - "Sure they didn’t ‘adjust’ your sway control bar, depending on what type of hitch you have, to maneuver the trailer at the shop?" - There was no maneuvering at the shop, the truck/trailer was in the same spot where I left it.

cajunmansion - "I’m getting the same thing." By this do you mean you are also getting some 'wiggle', but not really sway? Did you compensate for it by reducing speeds, or something? Or it really wasn't a big deal?

[cajunmansion]

Yes, getting some wiggle with new tires. The tires that came with the trailer was max 65psi. I do notice a big difference when a tractor trailer is passing me. I do not go over 65 MPH when pulling my trailer.

[Iwannacamp]

Maybe one of our tire experts will chime in.

I am about to do the same thing... D to E and did not foresee any sway issues....I know I have a 5th wheel. I also see many posts about towing better, so this is interesting to me.

[jadatis]

Now you are contradicting, in opening post , you wrote ,going from D- to E-load, and now you write C-load.

But did you measure the pressure with the 65psi valves, or did you assume the tires to be filled at 80 psi.

If you had even C- load in the past, 80 psi now is to high.

[RVEagle]

jadatis - "Now you are contradicting, in opening post , you wrote ,going from D- to E-load, and now you write C-load. But did you measure the pressure with the 65 psi valves, or did you assume the tires to be filled at 80 psi. If you had even C- load in the past, 80 psi now is to high." - Wow - your right - my mistake! I'm sorry about that. Yes, the original tires were "C" rated and I ran at 50 psi. The new tires are "E" rated and they were, and are, inflated to 80 psi - I did measure them.

Iwannacamp - "Maybe one of our tire experts will chime in." I'm hoping so (in addition to jadatis)! The more the merrier!

[babock]

Why are you inflating to 80PSI when you were ok with a load range C before? 65 will likely give you tons of margin.