Very stiff ride

[Ultraclassic]

I have 2017 Thor Four Winds Super C 35SM with 9300 miles on it. I have tried several tire pressure settings trying to keep the coach from self destructing when on most roads I have encountered. Now I am at 85psi all the way around and the ride is pretty good, but that is 25psi below recommend tire pressure. As the roads heat up this summer I feel that the tires will build too much heat plus being mounted on steel wheels heat doesn’t dissipate very fast. I have looked at the Firestone bolt on air bag for rear, but can’t find anyone that has installed on an application like this. Looking for any input that anyone might have.

[BFlinn181]

If you installed TPMS sensors on the valve stems, you'd be warned if the tire is generating too much heat. I'd also suggest getting the RV weighed, then look up the tire manufacturer's tables that shows pressure versus load. Perhaps your pressures aren't too out of line for the weight of the RV. Often the 'recommended' pressure is for maximum weight. If you aren't fully loaded, the tire pressure can be safely lower.

[momdoc]

Welcome. I agree get a TPMS system and figure out your actual weights.
Enjoy the adventure

[david.howard]

Originally Posted by Ultraclassic

I have 2017 Thor Four Winds Super C 35SM with 9300 miles on it. I have tried several tire pressure settings trying to keep the coach from self destructing when on most roads I have encountered. Now I am at 85psi all the way around and the ride is pretty good, but that is 25psi below recommend tire pressure. As the roads heat up this summer I feel that the tires will build too much heat plus being mounted on steel wheels heat doesn’t dissipate very fast. I have looked at the Firestone bolt on air bag for rear, but can’t find anyone that has installed on an application like this. Looking for any input that anyone might have.

I installed the Firestone Air Bags on my 2018 Coachmen Mirada shortly after purchasing the unit. The application data sheets said that they would not fit the Ford F-53 frame after 2014 because the bolt holes for mounting were not put in the frame by Ford any longer. I bought them anyway, measured and mounted them myself (being a former mechanic helps) and made a world of difference in the ride. It can be done with a little mechanical know how and common sense.
Also I run 95 PSI all the way around in my tires and with my TPMS system I watch the temps rise to about 115 when driving.
Also added a steering stabilizer (Roadmaster) and the motorhome rides and steers well.

[TonyDi]

Glad to have you here in the forum with us. You're gonna like it here.

Happy Trails!!!

[MSHappyCampers]

Hi ! Welcome to IRV2! We're sure glad you joined the gang!

I would not run those tires that low, no matter how rough the ride!

Good luck, happy trails, and God bless!

[Ultraclassic]

Thanks so much for your input on my problem! I’m ordering the air ride so I can get the tire pressure where it should be and order tpms also. I don’t think anyone fully understands how rough of a ride this thing has! It literally self destructs,the cabinet doors have mirrors in them and 2 of them fell out, the pull down blinds fall down and the tv came loose. But the big one was that the front cap where it attaches to the cab came loose and yes rain will come in when this happens. Gorilla clear packing tape works well. We put about 1200 miles on that tape and was still doing a good job. All warranty work so just a little inconvenience.Again thanks for your help.

[Mr_D]

Originally Posted by Ultraclassic

Thanks so much for your input on my problem! I’m ordering the air ride so I can get the tire pressure where it should be and order tpms also. I don’t think anyone fully understands how rough of a ride this thing has! It literally self destructs,the cabinet doors have mirrors in them and 2 of them fell out, the pull down blinds fall down and the tv came loose. But the big one was that the front cap where it attaches to the cab came loose and yes rain will come in when this happens. Gorilla clear packing tape works well. We put about 1200 miles on that tape and was still doing a good job. All warranty work so just a little inconvenience.Again thanks for your help.

Doesn't matter if we understand how rough the ride is or not. If you're running yhebtire pressure too low you are courting a blow out. Weigh the individual tire locations and sey the correct pressure for your brand, model and weight.

[TLGPE]

OK, do as others have suggested and get the coach weighed front and back at least, four corners if possible. From that you can determine what pressures you need. The nameplate recommendation may actually be 25 to 30 PSI too high; they are on our coach.

We all agree that running the pressures too low is dangerous, but you need to know what the correct pressures are. Your guesswork may be right on, but you need to know.

Tom

[avfordguy]

Ok so its on a ford F550 chassis, the ride should not be as harsh as what you say it is, what are you comparing it to? Will it ride as good as a 1/2 ton truck..no
Go to a CAT scale and weight it,and compare to chassis rating, weight placard should be inside one of the bedroom doors, see how much carry capacity you have, there are ways to soften the ride on superdutys, just have to know the weight numbers.

[brucev]

Originally Posted by Ultraclassic

I have 2017 Thor Four Winds Super C 35SM with 9300 miles on it. I have tried several tire pressure settings trying to keep the coach from self destructing when on most roads I have encountered. Now I am at 85psi all the way around and the ride is pretty good, but that is 25psi below recommend tire pressure. As the roads heat up this summer I feel that the tires will build too much heat plus being mounted on steel wheels heat doesn’t dissipate very fast. I have looked at the Firestone bolt on air bag for rear, but can’t find anyone that has installed on an application like this. Looking for any input that anyone might have.

Take a look at a thread I started on The Thor Forum, "Need help with miserable ride" I have been suffering the same problem. I Talked with the guy at Bilstien and he suggested I upgrade to the aftermarket Bilstiens. I replaced the front last weekend and they helped a lot. Will be replacing the rears when they come in. In the F53 chassis it will never ride nice but can be improved. I also downloaded the Goodyear RV guide and found I am running a few pounds more pressure than I need to. I have the four corner weights and according to Goodyear I only need to run 80 PSI all around rather than 85 rear and 82 front.

You will find links to the goodyear site and a PDF of the inflation guide, that is if you have good years. PM me if you want to know more. Here is a link to the thread.

Need Help With Miserable Ride - Thor Forums

[avfordguy]

https://kelderman.com/shop/2017-ford...air-suspension

[GGC]

Think like you're driving a truck, you are quite similar. If you are falling apart, Thor is a BIG PART of the problem and try slowing down some. Five mph or so will keep your teeth in a little longer. What speed do you normally drive at anyway?
My first MH was a 23' Four winds, gone in less than a year. Not a road worthy vehicle. That's just MHO.

[Ultraclassic]

Thanks for all of the very helpful information. As soon as I get it back from repairs I will start working with the suggestions that have been made and I will let y’all know what works best.