Severe & sudden rear end weave

[ourbreather]

After driving our 1999 Windsor some 8-10 miles Memorial weekend, I took it to the RV shop last week and the coach felt like I was driving a big fish down the road. The rear end would not track straight and I had to keep my speed below 40 MPH.

I've seen recommendations for shock and airbag replacement. As for the airbags, the unit sits level and doesn't tip vertically. It's the horizontal movement that is frightening as the rear end wants to veer either across the yellow line or onto the shoulder.

I just don't have a local shop in our area. Any suggestions as to what could cause this sudden and severe change in the coach's performance?

Any help is appreciated. I have the coach at a local tire/alignment shop, but they are not an RV chassis shop. We have a couple committed to purchase our coach, and it must be roadworthy to fulfill the sale.

Any ideas?

[Stretch]

From what I have read in the past on this website your rear suspension may have broken. There is a fix for it. Someone will chime in with the fix.

[Mr_D]

Originally Posted by Stretch

From what I have read in the past on this website your rear suspension may have broken. There is a fix for it. Someone will chime in with the fix.

Check with Source Engineering, they don't list anything for that year rig but give them a call anyway as they might be able to do something for you. 541-343-0293

[jacwjames]

First thing to check is to make sure the axle supports are still solid with nothing broke. The Axle rides in (and is attached to) a large frame that the 4 air bags are attached to. There are stabilizer bars that keep everything straight and aligned but let the whole system work up and down. Check to see if everything looks like it should.

Also check to make sure both leveling valves are hooked up, this is what controls the coaches ride height. There are 2 for the rear and they are attached the axle with a connecting link that attaches to the valve arm which are attached to the chassis.

I have heard of a couple of reports where the axle supports have cracked/broken. They can be fixed but it's not a easy/cheap job.

[Dr4Film]

The coach needs to go to a reputable truck chassis shop for inspection and evaluation.

Where it is now won't help you except for taking up space.

Dr4Film ----- Richard

[SuperSteer]

If it is a RR4R chassis a rear trailing arm may have broken, The original design was prone to failure, upgraded replacements are available from a few vendors (including us

[pphake]

The aft suspension of my 1999 Windsor also would cause hazardous weaving in high winds or when I was passed by a tractor trailer. Turns out the suspension bushings in the rear are a known problem. The bushing spacer material was a plastic that crumbled over the years. You will find other postings on this exact problem and the solution is replacement. The torque bars that are held by the bushings can no longer do their job and the entire rear suspension can shift laterally 1-2 inches when under stress. All 10 rear bushings should be replaced. A new version of the bushings can be purchased from Monaco. My problems disappeared when I had the rear bushings replaced. Another problem that others have reported, is that the huge steel members that support the axle assembly can crack at weld points (possibly from improper towing) and can result in a loose rear suspension that jolts when driving. I learned about these cracks on irv2 but hopefully do not have them. Visit a heavy truck suspension specialist and wear your lucky hat!