My platform is 1993 fleetwood coronado class a p30 with rear disk brakes (p32?) and 454. I put 6 new tires on it a few months ago and a shake developed as soon as i got it back from the tire shop, so i assumed it was the tires. They are sumihoto 8r19.5. They were not the cheapest tires i could get. I never cheap out on tires. Anyway the rig has been back to the shop about a half a dozen times for this shake and it has not changed. They replace something say its fixed, and then the truck behaves exactly the same. So far ive done 4 new bilstien shocks, bilstien steering stabilizer, supersteer trac bar upgrade, 2 new rims, 2 of the new tires replaced (warrantied). The front end is tight, springs and airbags are fairly new and i keep the bags at 80psi. Ive experimented with different bag pressures and never noticed a difference. If i continue to pour money into this pile of junk im going to change to non bag coil springs from supersteer. Thats would pretty much be the last thing i could think of. Unless my wheel cover simulators are making it shake, which i didnt think of until just now. The shake feels like an up and down shutter. It starts at 60 and gets worse as you accelerate. I will say the truck drives very steady and feels safe with all the new parts, it just shakes. Which is agonizing.

That sure sounds like an out of balance wheel to me. One thing to check (far from the only possibility) is that the wheel balance weights are tightly attached and not shifting around. I've had some that were apparently not properly crimped on the rim and when they shift it's all sorts of annoyance.

Sounds more like an out of round tire. Use your levelers and raise the tires off the ground and watch them as they rotate. you should see a tire that is out of round enough to cause a shake. Of course it could also be a bent wheel which will also show up. There are also rings that are in the rubber tire itself and you can check them against the metal edge of the wheel to see if the bead had seated evenly or is off center.

It does sound like out of balance wheel. Do you feel it in the steering (does the steering wheel shake) or just the ride? Assuming each wheel has been fully balanced off the vehicle at least twice as you indicate, and assuming those doing the balancing are competent it must be something on the vehicle. The problem starting coincidental to the tire change points to tires, but there are obviously other potential unrelated causes. Out of balance drums or rotors is one potential but would most likely be more noticeable in braking. Wheel bearings could also be a potential problem. One thing worth checking would be to check each wheel position's hub temperature after driving some distance. The should be relatively uniform. Any axle or bearing issues could cause higher temperatures at one of the wheel locations.

Probably too late now, but I would have insisted on first a complete rebalance of the tires and then 6 new or different tires as a test long before I started spending money on other replacement parts. If as you say your shake started as soon as the new tires went on then then it stands to reason that the tires are the cause. Hopefully you and the shop have some kind of good working relationship. Ask them to hold on to a set of appropriately sized tires removed from another coach and give you a call. Take the coach down and swap tires and go for a drive. Or have them replace one tire and swap it to all different tire positions on the coach with a test drive between swaps. This test isn't as accurate since you could have more than one tire problem, but it is a start.

Find a tire shop with a Hunter Engineering GSP9700 Road Force wheel balancer. It tests tires for out of round and hard spots. Sometimes, the tire can be rotated a little on the rim to achieve a better match giving you a better ride. Purcell Tire here in St Louis has one and charged me $30 a tire to check mine. Download a pamphlet explaining the features of the GPS9700 Road Force Elite Here's link to find one near you: (there's several on Long Island)https://www.hunter.com/gsp9700The frequency of the vibration should lead you to the source. Tires are one frequency, a drive-shaft is another (more frequent).

I got the shakes | Good Sam Community

DrewE
Explorer II
Sep 15, 2019
That sure sounds like an out of balance wheel to me. One thing to check (far from the only possibility) is that the wheel balance weights are tightly attached and not shifting around. I've had some that were apparently not properly crimped on the rim and when they shift it's all sorts of annoyance.
rgatijnet1
Explorer III
Sep 15, 2019
Sounds more like an out of round tire. Use your levelers and raise the tires off the ground and watch them as they rotate. you should see a tire that is out of round enough to cause a shake. Of course it could also be a bent wheel which will also show up.
There are also rings that are in the rubber tire itself and you can check them against the metal edge of the wheel to see if the bead had seated evenly or is off center.
happy2rv
Explorer
Sep 15, 2019
It does sound like out of balance wheel. Do you feel it in the steering (does the steering wheel shake) or just the ride? Assuming each wheel has been fully balanced off the vehicle at least twice as you indicate, and assuming those doing the balancing are competent it must be something on the vehicle. The problem starting coincidental to the tire change points to tires, but there are obviously other potential unrelated causes. Out of balance drums or rotors is one potential but would most likely be more noticeable in braking. Wheel bearings could also be a potential problem. One thing worth checking would be to check each wheel position's hub temperature after driving some distance. The should be relatively uniform. Any axle or bearing issues could cause higher temperatures at one of the wheel locations.
opnspaces
Navigator II
Sep 15, 2019
Probably too late now, but I would have insisted on first a complete rebalance of the tires and then 6 new or different tires as a test long before I started spending money on other replacement parts.

If as you say your shake started as soon as the new tires went on then then it stands to reason that the tires are the cause. Hopefully you and the shop have some kind of good working relationship. Ask them to hold on to a set of appropriately sized tires removed from another coach and give you a call. Take the coach down and swap tires and go for a drive.

Or have them replace one tire and swap it to all different tire positions on the coach with a test drive between swaps. This test isn't as accurate since you could have more than one tire problem, but it is a start.
DFord
Explorer
Sep 15, 2019
Find a tire shop with a Hunter Engineering GSP9700 Road Force wheel balancer. It tests tires for out of round and hard spots. Sometimes, the tire can be rotated a little on the rim to achieve a better match giving you a better ride. Purcell Tire here in St Louis has one and charged me $30 a tire to check mine. Download a pamphlet explaining the features of the GPS9700 Road Force Elite

Here's link to find one near you: (there's several on Long Island)
https://www.hunter.com/gsp9700

The frequency of the vibration should lead you to the source. Tires are one frequency, a drive-shaft is another (more frequent).
Executive45
Explorer III
Sep 15, 2019
Register my vote for an out of round tire. Almost any tire shop can put a 19.5 tire on their balancer. Obviously having them balanced ON THE COACH is the best way but if they spin balance them, you should be able to find which one is bad....Dennis
wa8yxm
Explorer III
Sep 15, 2019
I am with Drew and others "Sounds more like an out of round tire."

but the suspect list includes the U-Joints and a few other things

Another thing, rare though it happens, is an out of ROUND tire
I have heard of that (just one case, former fiance's Father)
Executive45
Explorer III
Sep 16, 2019
In my lifetime, I've experienced two out of round tires. PITA, but balancing while on the vehicle is the easiest way to highlight it. Whether the mfg will exchange it is another issue completely....good luck...Dennis
olfarmer
Explorer II
Sep 16, 2019
The above comments are all good but I would take off those wheel covers and do a test drive, just to rule out that as a possibility!
Scottiemom
Nomad
Sep 16, 2019
We also have our coach aligned after new tires.

Dale

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