07 Dynasty Tire/shocks

[Life Style]

07 Dynasty 30k miles.
First trip home from dealer a front Bilstein shock blow-out. Replaced and next trip another different front shock blow-out. Replaced and determined level ride was not adjusted properly. No Bilstien failure since adjusting.
However at 30K miles both front 670 Goodyear tires have a wavy ware pattern on both outer and inside edges. Had front alignment inspected, no problems. Goodyear states under inflated and to increase to 125psi. which is max for this tire. Tire pressure was 110 frt, 100 Dr. & 95Tag. Do not have axles weights but planning to do so.
I think it is a shock issue and would like to know if any Dynasty members with the 10 air bag ride have switched to Koni. If so was it worth the investment?

Thanks for reading my post.
Tom

[Mike Canter]

Tom, I have 36,000 miles on my 2004 Signature and the Goodyear tires are also wearing on the the outer edges and the tread is still good. According to all that I have read on several forums is that this is a problem with the Goodyear tires called "rivering". Six thousand miles ago (because of aging) I switched my front tires to Michelin XZA2 Energys and am very happy so far but time will tell. I also upped the size on my front tires to a 315/80r which is a 20 ply tire and only makes a half inch difference in ride height. That chassis carries a lot of weight on the front. I will leave the back tire size alone when I change them.

You indicated that you have a tag axle and was wondering what you have the pressure regulator in the engine compartment set at for the tag airbags. In case you didn't know that regulator changes the weight distribution on the chassis by a lot. Several of us are running the regulators at 40 psi and it seems good. When I upped it from 28 psi to 40 psi the temperatures of my rear tires dropped. It takes several adjustments to get it right at 40 lbs. I would make an adjustment then when I stopped I would check it and make a small adjustment until it came right on. If you make big adjustments you will chase your tail.

My Signature tire pressure chart from the factory say to run 115 psi in the front, 100 on the drive axle and 85 on the tag axle. Have you checked the sticker. My stickers were located both on the wall behind the drivers seat and in the back closet. Since I put the bigger tires on the front I have dropped my front pressures down to 110 lbs because of the greater load carring capability of the tires. Yes weighing the MH is the best way to get the correct tire pressures.

As far as the Bilstein shocks I think you would regret switching to Koni's. I tried them on another MH and the ride was way too harsh. Even with the Bilsteins you have to stay with the comfort shock model. When you say you blew out a shock are you saying that they started to leak oil or what? I think that adjusting the ride height may have fixed your problem on the shocks. Have you had all the rest of the shocks taken off the MH and checked. If the ride height was way off on blew out two shocks then maybe more are damaged and not leaking oil but is causing a greater load on the other shocks. One thing is that those new Bilsteins that you have put on are guaranteed for life make sure you keep the receipts.

[Dutch Star Don]

Tom....Rivering is the term tey're using. It has to do with Goodyears design so that the tire steer's better. In my readings, they recommend running the Goddyear tires at 5 pounds higher than the recommended weight from the Goodyear weight charge.

You really need to get axle weights before you do anything else. At minimum, get the front weighed and then go to the Goodyear chart for the correct pressure for that tire. http://www.goodyear.com/rv/pdf/rv_inflation.pdf

[Downsizer]

Another thing to consider is your ride height. The chassis can be "perfectly" aligned and all well. If the front air bags are keeping the coach too high up there, it will cause serious cupping, rivering, whatever you want to call it ($$$$$$ out!!!!). As you drive over our wonderful highways, the coach will react and move up and down. If the shocks are forced to try to control the coach that is too high in the front, it will wear out the shocks too quickly and worse, cause very serious wear on those $$$$ tires!!! A huge benefit of the air bag suspension is the separation of coach and chassis..... ride height of the coach to chassis is critical to tire wear and especially cupping of the outer edge on the tires

[moisheh]

I have never heard the term blow out when it comes to shocks. Did they leak or break? Read this and any other RV forum and you will soon see that Konis are the shock of choice. On our Dynasty (08) I changed the front shocks when the unit was only 6 months old. Made a big difference in tide quality. I would not fool with the tag axle pressure. Adjusting this valve will alter the weight balance to either the front or rear axle. It will also change your ride height. This will require a wheel alignment. Best left to experts. Before changing tag pressures you need to weigh every wheel. You have a fine MH and is consdired to be one of the best riding units on the market.

[Mike Canter]

Changing the tag axle pressure will not change the ride height. The ride height adjuster valves compensate and keep it set at the same level. The tag axle adjustor is set at 28 psi at the factory as just a standard adjustment on all tag axle motorhomes and may not be correct for yours. I agree the best way to do it is on the scales.

[Life Style]

I thank each of you for your input regarding our 07 Dynasty tire issue.
Mike, I believe “Rivering” is the correct identification of problem.
Factory chart reads 120frt. 95dr. 90tag. I increased steer tires from 110 to 120.
Tag pressure was set at 45psi. Have no idea how it got set that high. Could have been adjusted at the same time ride level was corrected. I corrected to 30psi following tag procedure.

Diplomat Don
I will use the above changes until mid October when chassis is weighed.

Downsizer
Bernie, The ride height is set at factory spec, 9.5 inches to center of bag.

Moisheh
Re; Blow-out. These shocks damaged themselves because of incorrect ride level and literally dumped oil.
Tag pressure does effect weight distribution but ride height is not effected with pressure change.
Thank you. Tom

[Eaglesview]

Shock issues aside, the G670's do not have a decoupling groove. Even my rear tires show this wear pattern to some extent. Original G670's at 69,000 miles on a Dynasty operated at 5+ psi but will be going to a Michelin, despite the fact the XZA2 does not have the decoupling groove.

Where has this love affair with Konis originated?

[Mike Canter]

So what is a decoupling groove? Since both the Goodyear G-670s and the Michelin XZA2 tires do not use it the tire engineers must think that it is not required.

In a shock test in a motorhome magazine the Bilsteins were rated as the best in ride and control.

Something to remember....when I purchased by Michelin tires iI traded my G670s in for $100 each. The tire place said they would do that if no craking on the sidewalls.

I am interested in knowing why the incorrect ride height will "blow out" a shock. The ride heights the we say that are off are probably not off more than a inch. The shock travel is far more than that and ride height should not damage the oil seals.

[Life Style]

Mike, according to the mechanic at the two different repair shops, both said the shocks bottomed out. The second shop to do this repair was Massy (Truck Repair) in Phoenix and they contacted Monaco to correct ride height.
I recommend Massy on So. 58th Phoenix. The oil did not weep out of shocks it dumped. Shocks failed in first month of use. Can't say it was defective shocks because after ride level correction no more shock problems. I was thinking of purchasing new Koni shocks but your knowledge about rivering changed my mind.

[Life Style]

Mike, I believe Michelin has a groove pattern on outer edges. Check your tires, Goodyear has no groove or syping. (Syping??)

Tom

[Mike Canter]

I will have to go and double check but I think it has solid shoulders but I will check. When I put those Michelins on one tire required zero balance weight and the other took only 6 oz which is impressive on a big tire like that.

The ride height would have to be pretty far off for those shocks to bottom. I came through the middle of San Antonio a couple of months ago and it a couple of bumps in a row and I swear I was airborne. Scared me to death but my shocks survived. It was really bad. Warning to all MHs driving through downtown San Antonio.

[JFC]

Smaller coach, but my 2002 Ambassador had rivering on the front Goodyears at 18K miles. Changed to Blistein shocks in front, no improvement in tires wear. Tires a mess by 24K miles. Replaced with Toyo and had no problems for the next 40K miles when I traded for a new Scepter in 2007. Had front end alignment checkd on Scepter at 12K miles as well as had front tires spin balanced. At 37K miles, front Goodyears rivering badly. Will probably replace with Bridgestone this month.

[Life Style]

Hi JFC

Wonder why you choose Bridgestone when you had success using Toyo??